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Pastoral agriculture influences both the food resources available for the soil food-web, and soil physical conditions. This study explored the relationship between food resources, soil physical condition, and soil invertebrates in 42 grazed pastures across different soils in New Zealand. The response of invertebrates to food resources and soil physical conditions was associated with both the size class of invertebrates (i.e., earthworm vs. nematode) and functional group (i.e., bacterial-feeding vs. plant-feeding). Changes in soil pore size, a surrogate for habitable pores, was correlated with the invertebrate community across the soils in the study, more so than potential food resources from plant litter and dung calculated from livestock numbers. Overall, management practices which improve habitable pores in the soil are beneficial not only for plant growth, but also for sustaining the diversity and abundance of the biological community which contribute to the soil services required for pasture agriculture. An invertebrate indicator, that included the abundance thresholds of each invertebrate group at which their activity would be insufficient to sustain the soil processes, would give land managers a tool to identify deficiencies in the invertebrate community and assess the implications of these deficiencies on the ability of the soil to provide the necessary ecosystem services.

Soil invertebrates have limited defences against moisture stress but little is understood of how irrigation influences their community. This paper investigates the influence of five summer irrigation schedules on earthworms over a 15-month period in a long-term pasture irrigation study. The influence of the two extreme rates of irrigation on other soil invertebrates was also examined. The effects of frequent drought periods under dryland pasture favoured small and short-lived nematodes and oribatids. During wetter months, earthworm abundances were similar between dryland and irrigated treatments, while earthworms tended to migrate down the soil profile and aestivate in response to soil water deficits during summer. The higher abundance of earthworms in the summer months under irrigation may partly explain the lower soil carbon found under irrigation, due to enhanced rates of soil organic matter turnover, despite higher primary production and inputs of carbon. It is thus important to consider irri...

1. The reproductive fitness of a parasitoid depends on its mating and ovipositing success. Virgin haplodiploid females can reproduce, but produce only males, and may diminish fitness by producing more male offspring than required. Therefore, females must decide on whether to mate or oviposit first. 2. This study was conducted to assess the mating versus ovipositing decision and its impact on the reproductive fitness of Diaeretiella rapae (Hymenoptera: Aphididae), an endoparasitoid of the cabbage aphid Brevicoryne brassicae (Hemiptera: Aphididae). 3. When newly emerged females were given a choice between mating and ovipositing, about 62% of D. rapae females preferred to mate before ovipositing. Those females who oviposited before mating parasitised only 10% of the available aphids. After mating, females superparasitised their hosts with fertilised eggs, which resulted in a highly female-biased sex ratio in the offspring. 4. Mating success was very high (91%) in the presence of hosts (cabbage aphid nymphs) compared with that in the absence of aphids. However, mating success was not influenced by the quality (size) of the hosts present in the mating arena, despite a parasitoid preference for larger hosts during oviposition. The time between pairing and mating was also shorter in the presence of host aphids. The mean number of aphids parasitised and the parasitism rate were significantly greater after mating.

Host age-dependent fitness of Diaeretiella rapae was studied on cabbage aphid Brevicoryne brassicae. When given a choice of nymphs of four different ages (1, 3, 5 and 7 days), females showed a strong preference for oviposition in older nymphs, which were also the largest in the body size, and left the majority of younger nymphs unparasitised. More than 70% of offspring emerged from 5-day and 7-day old parasitised nymphs. Parasitoids develop faster in older hosts than in younger hosts. Development time of males was shorter than females in older hosts, but the development time of males and females was similar in younger hosts. The body size of adult D. rapae was positively correlated with the age of the hosts in which they developed. The sex ratio of offspring was found to be female-biased. A higher proportion of females emerged from older hosts. D. rapae females emerged from older hosts lived significantly longer. The potential fecundity of the females emerged from older (larger in body size) hosts was significantly greater than of those emerged from younger hosts with smaller bodies. Results suggest that D. rapae preferred older hosts to maximise the reproductive fitness gain. The oviposition strategy of D. rapae is discussed in the context of efficiency of this parasitoid in biological control programmes.

Soil invertebrates are coming under increasing pressure as pastoral agriculture is intensified. Grazing livestock affects the soil invertebrate community by impacting on the physical habitat through treading, and on nutrient cycling through dung and urine return. In this study the sensitivity of soil invertebrates to livestock was examined by quantifying the abundance and diversity of invertebrates in the grazed pasture and comparing it with those under adjacent permanent fence lines on three different soil types at three locations. Resilience of the invertebrate communities was also explored by sampling mown, fertilised and irrigated plots within grazed pastures, where livestock had been excluded for the previous three years. Of the soil invertebrates the predatory and omnivorous nematodes, Oribatida and predatory macrofauna were the most sensitive to grazing livestock. In comparison, earthworms with their higher mobility and ability to burrow were more resistant to livestock. The combined effect of removing treading pressure and moisture stress in the fenced plots appeared to be the major factors influencing invertebrate recovery, rather than the quantity and quality of food entering the soil food-web as influenced by fertiliser application. Earthworms, exhibited the greatest resilience, doubling in abundance in the mown and irrigated plots. Nematodes were more resilient than the larger and longer-lived Oribatida. The oribatid community in the irrigated and mown plots were limited in both diversity and abundance in comparison to the community under the fence line. That the vulnerability of soil invertebrates to livestock treading was consistent at all three sites would suggest that organism characteristics (i.e., life-history and ability to move through the soil) and trophic interactions are important in structuring the biological community.

Reproductive activities of naturally occurring population of Diaeretiella rapae (M'Intosh) (Hymenoptera: Aphidiinae) on Myzus persicae were studied during spring season in New Zealand. The cabbage seedlings were highly infested with the aphids (272±25 individuals/plant) with about 30% on average parasitised by D. rapae. Rate of parasitism was positively correlated with the aphid density (R 2=0.64). Adult emergence from aphid mummies was 90%, with a higher frequency of females than males. Increase in female/male sex ratio was found between early and late spring (1.1 vs. 1.8). Mating in D. rapae occurred throughout the day. Nearly half of the mating pairs collected were male–male pairs, which were especially prevalent during morning and evening while more male–female mating pairs were found during midday. Male–male mounting was probably because of low number of virgin females in morning and evening populations. About 80% females were mounted by smaller size males. Male–male mounting is discussed in...

Earthworms play an important role as primary decomposers in the incorporation and initial mixing of plant litter. This study explored the response of earthworms to increasing fertiliser inputs, pasture production and livestock numbers (and their influence on food availability and soil physical condition) on six different managements in sheep-grazed and fifteen different managements in dairy-grazed pastures in a variety of New Zealand soils. Native earthworms were only found in some low-fertility pastures. Accidentally introduced peregrine earthworms, when present, dominate pasture soils. Of these, endogeic earthworms dominated the earthworm community and were positively associated with soil types with higher bulk densities. Peregrine anecic earthworms were absent from most hill-country sheep-grazed pastures, however in more fertile and productive dairy-grazed pastures they reached a biomass of up to 2370 kg ha−1. Only anecic earthworms showed a positive response to the increasing pressures associated with higher potential dry matter inputs and liveweight loadings of grazing livestock on soil, while epigeic earthworms declined. The positive response of anecic earthworms probably reflects the combined effect of the increase in food resources, including dung and plant litter, available on the soil surface, and their lower susceptibility to livestock treading pressure. Anecic species may be a suitable substitute for incorporation of surface litter in those soils where livestock treading limits epigeic earthworm populations. This study confirmed previous observations of limited distribution of the introduced Aporrectodea longa in pastoral hill-country soils in the North Island, and their near absolute absence from the South Island of New Zealand. This would suggest that large areas of New Zealand pastoral farmed soils could benefit from the introduction of anecic species from other parts of New Zealand which already contain A. longa.

Organic management aims to promote soil biological activity. To test whether organic management stimulates soil biological activity, invertebrates (macrofauna, mesofauna and microfauna) were collected from four paired commercial organically and conventionally managed dairy farms on different soil types (Allophanic, Pallic, Recent and flooded Recent). Food webs were constructed and rates of invertebrate-mediated N mineralisation calculated. The organic dairy operations used fewer nutrient inputs and had lower stocking rates than their paired conventional farms. This translated into lower calculated pasture production and less available plant litter entering the soil food web. Despite the lower plant litter inputs into the organic system, earthworm biomass was higher (particularly in the Recent and flooded Recent soils), suggesting that under conventional management the physical condition of the soil, as influenced by stock treading pressures, was more important for invertebrate activity and their influence on N mineralisation than was food supply. Nitrogen mineralisation was higher in organic systems, with earthworms contributing the most (24–98 kg N/ha/year). As the physical loading on the soil increased under conventional management, the ability of the soil to provide soil services (i.e. N mineralisation and litter decomposition) became compromised. Organic management on four soils stimulated biological activity by reducing the treading pressure on the soil and highlights the need to consider the influence of management practices on the faunal environment (food availability and physical condition) to understand the impacts of organic management and the role of fauna in N mineralisation.

Earthworm abundance increased and Oribatida abundance decreased on a Brown soil with increasing inputs of phosphorus (P) fertiliser and sheep stocking rates. To determine if the same response to increasing management intensity is found in Allophanic soil, samples were collected from a long-term sheep-grazed trial with two contrasting management regimes, low and high intensity. As pastures on the Allophanic soil became more productive and were grazed with more sheep, there was a tendency for earthworm abundance to increase and oribatid abundance to decrease. Both these trends were consistent with those on the Brown soil, supporting the potential of earthworms and Oribatida as biological indicators. Oribatid mites, which produce nutrient rich faecal pellets, were positively correlated with porosity. The higher earthworm abundances in more intensive sheep grazed pastures may have a positive influence on ecosystem services such as air and water movement, and organic matter incorporation.

Organic pasture management includes a focus on mixed livestock grazing, restrictions on nutrient inputs and livestock pest control. These are all factors which influence the environment of soil invertebrates. In this study, soil macrofauna, mesofauna and microfauna were collected from duplicate 11 and 20 year old organic and conventional legume-based sheep-grazed pasture systems. Pastures in both systems had received the same annual input of reactive phosphate rock and elemental sulphur and were stocked with the same numbers of sheep. The major difference between the two systems was absence of the chemical control of livestock pests on the organic system, resulting in lower sheep liveweights. Two ungrazed pastures which had not received any nutrient inputs for 20+ years were also sampled as part of the study to provide an additional contrast. No significant differences in either the diversity or abundance of the soil invertebrate community were found between the organic and conventional systems, despite the use of chemicals in the conventional system. The lack of difference suggests that many of the observed and reported responses to organic management reflect altered nutrient inputs and grazing management (which were the same in the current study), rather than the cessation of chemical controls in the organic system. In contrast, the invertebrate community in the unfertilised, ungrazed pasture was distinctly different from both the grazed systems. The ungrazed pasture had a higher diversity with more New Zealand endemic species than the grazed pasture. This included twice as many large Oribatida as soil pore size increased. The lower litter quality from the lack of nutrient inputs in the ungrazed pasture was reflected in both lower earthworm abundance and the Nematode Channel Ratio (indicative of a higher proportion of fungal- than bacterial-feeding nematodes), than the grazed pasture. We conclude that organic management when limited to a comparison of livestock pest control is not beneficial to soil invertebrates. Management practices such as stocking rates and fertiliser regime, by altering the soil physical environment and food resources, are more important in influencing invertebrate populations in this soil. Some would argue these altered management practices are an integral part of an organic production system.

Carbon footprint is widely accepted as an indicator of greenhouse gas emissions and global warming. Modeling carbon footprints based on life cycle assessment is applied as a way to evaluate the net contribution of greenhouse gases to the atmosphere from orchard production systems over one growing year. This net balance approach considers the sources and sinks of carbon and therefore provides a better reflection of an orchard system's net contribution to climate change. Carbon footprinting of organic kiwifruit and apple production systems in New Zealand indicated that the studied systems had a net sequestration from 2.4 to 5 t of CO2e/ha/year and therefore can be potentially considered as carbon sinks under the Kyoto Protocol. This finding implies that the organic kiwifruit and apple orchardist can gain a monetary benefit by earning carbon credits. However, further research to improve and validate this approach is essential before it can be practically used for decision-making at the orchard level and for policymaking at the national level.

Superparasitism (repeated oviposition in same host) indicates either a fitness benefit for the parasitoid, or an inability of ovipositing females to discriminate parasitised versus unparasitised hosts. Superparasitism in Diaeretiella rapae, the solitary endoparasitoid of cabbage aphid Brevicoryne brassicae, was studied in the laboratory. When given a choice of parasitised and unparasitised aphids, 70% of females made their attack on unparasitised hosts first, even though already-parasitised aphids were less defensive to parasitoid attack and ovipositing females had shorter host-handling time. The female superparasitised hosts during repeated attack and the large hosts were superparasitised more often than the small ones. Although superparasitised hosts carried two to five parasitoid larvae, only one larva developed into an adult. The body size of parasitoid larvae, as measured 4 days after oviposition, was affected by the total number of larvae in the host. Superparasitism strategies of D. rapae are discussed in the context of reproductive fitness.

Five species of Pauropoda belonging to four genera have been identified from New Zealand. The genus Samarangopus is reported from there for the first time. Four new species are described by the first author: one in Pauropodidae, Decapauropus whanganuiensis n. sp., two in Eurypauropodidae, Samarangopus plicatus n. sp. and S. constellatus n. sp., and one in a new family, Eirmopauropodidae, Eirmopauropus distichos n. gen., n. sp. The new family Eirmopauropodidae is diagnosed as having head and pygidium free, not covered by 1st and 6th tergite respectively; head and tergites sclerotised with setae in regular transversal rows.

The impact on soil invertebrates of changes in the physical environment and feed availability in intensive pastoral systems is difficult to predict given the number of interacting factors. This study explores the influence of a change in defoliation regimes (pastoral fallow, cut and carry, cow grazing), feed type and availability to ruminants (pasture and pasture supplemented with maize) and dairy cow stocking rates (3, 4 and 5 cows ha −1 ) on the abundance and diversity of soil invertebrates (macrofauna, mesofauna and microfauna). Samples were collected from two depths (0–7.5 and 7.5–15 cm) on a well-structured loamy Andosol soil in two seasons (autumn and winter). Treatments allowed an independent assessment of the influence of changes in food sources to the soil food-web from that of physical disturbance from livestock treading. There was a clear distinction in habitable pore space between the fallow and other treatments. The high porosity under fallow (28% under fallow vs. 11–13% under other treatments) appears to be an important factor, increasing faunal abundance and biomass, including macrofaunal predators and Oribatida. Large inputs of litter under fallow benefited epigeic earthworms and resulted in a dominance of bacterial-feeding nematodes (Nematode Channel Ratio 0.97), reflecting the still high quality litter from previous management. Grazed pastures had higher abundances of plant-feeding and plant-associated nematodes as they were stimulated by increased root growth (abundances up to 1.2 × 10 6 ind m −2 ). While there was little difference in total earthworm abundance between treatments, anecic A. longa became progressively more abundant under higher cow stocking rates as food availability and physical pressure increased (18 ind m −2 vs. 128 ind m −2 , under 3 and 5 cows ha −1 , respectively). Initial earthworm functional diversity is important and we suggest that anecic earthworms can substitute for epigeic earthworms in intensively managed pastoral systems by incorporating litter, as well as being important ecosystem engineers.

Ethanedinitrile (EDN) is a potential alternative fumigant to methyl bromide for the phytosanitary treatment of timber and logs. Previously, adult golden-haired bark beetles (Hylurgus ligniperda) have shown high rates of tolerance to EDN, while all life stages of burnt-pine longhorn beetles (Arhopalus ferus) were highly susceptible. These results suggest that the fumigant mode of action might be species-specific and more complex than previously thought. Therefore, the anatomy of these beetles was examined to investigate potential differences in EDN toxicity related to these insect traits. The mesothoracic and fourth abdominal cuticles of 20 individuals were measured and compared across the two species. Spiracle sizes of 20 adult insects were also measured and compared across and within species. Of the two species, A. ferus had the thicker dorsal thoracic and abdominal cuticle. Adults of A. ferus had also the larger total spiracle area. These results provide important information to help explain the observed differences in EDN tolerance across the two species. Further work will test the main route of entry of EDN into the bodies of target insects and additional effects on EDN on insect behaviour.

The population structure and dynamics of bronze beetle, Eucolaspis spp., and other soil macro-invertebrates were studied in eight organic apple orchards in Hawke's Bay during spring/summer 2007-08. Orchards with high bronze beetle population densities also had higher abundance of all types of soil macro-invertebrates than orchards with low bronze beetle populations. Surface-dwelling generalist predators were more numerous (on average 53.6 versus 40.5 predators per trap) in orchards with low bronze beetle density than in orchards with high beetle density. This result was mainly due to spider numbers in pit-fall traps, which were highest during January. It may be that within orchards where surface- dwelling spiders are most abundant, these spiders may be predating upon newly emergent adult bronze beetles as they move from the soil to the apple foliage.

Surface energy balance and 24-h evapotranspiration were mapped on an agricultural landscape with SRF willows using a remote sensing-based model to provide information on the water use by different land cover types. The results demonstrate the influence of land cover and vegetation type on surface energy balance and water losses. The evapotranspiration from forests was much higher than for other land cover types, corresponding to the significant cooling of the land surface. The SRF willow plantings were on average 3.6 °C cooler than the surrounding grassy areas; the 24-hour evapotranspiration from willows was 1.6 times higher than the evapotranspiration from surrounding grass, but lower than evapotranspiration from the forests. The possibility of changes in evapotranspiration patterns, local climate, and regional water balance with increasing acreage in SRF crop are discussed.

This study examined the influence of superphosphate fertiliser application and sheep stocking rate on the density and diversity of soil macro- and mesofauna, particularly earthworms and oribatid mites in two sheep-grazed New Zealand hill pastures. The low-intensity (LI) long-term experimental farmlet is managed with no fertiliser and a low sheep stocking rate (9 stock units/ha); the high-intensity (HI) farmlet receives 34 kg P/ha/yr and has a high sheep stocking rate (16 stock units/ha). Soil mesofaunal samples were collected at two depths (0–7.5 cm and 7.5–15 cm). Earthworm species, major mesofaunal groups and oribatid species were identified, and the trophic groups, body size, biomass, mode of reproduction and global distribution of oribatid species established. Soil fertility, temperature, moisture, and pasture composition were also measured. The study tested the hypotheses that intensive pasture will have fewer native species, and among Oribatida, lower proportion of fungivores, higher proportion of asexuals, and higher proportion of smaller species with shorter life cycles. The results reflect the complex effect of intensive pasture management on soil organisms. Earthworm densities were higher in the intensive pasture system, with the exception of endemic Octochaetus multiporus. The low-intensity pasture system, where soil C:N ratio was wider, sheep stocking rate was lower and earthworm numbers were lower, supported higher density and diversity of soil mesofauna and Oribatida, which were concentrated in the topsoil (0–7.5 cm depth). In the high-intensity pasture system the zone of biological activity was expanded vertically—the mesofauna and Oribatida, although lower overall in density and diversity, were more evenly distributed between the 0–7.5 cm and 7.5–15 cm soil depths, suggesting reduced effect of livestock treading and greater food availability at depth. Pastoral intensification influenced oribatid trophic structure, with fungivorous species dominant in LI and herbofungivorous species in HI pasture, which probably reflected underlying differences in food resources, such as more fresh root biomass in HI. There was some evidence suggesting a shift to short-lived, cosmopolitan, and asexually reproducing Oribatida in HI at 0–7.5 cm soil depth. Oribatid density (which reflected mesofaunal densities), overall diversity, trophic groups, life-history characteristics and especially vertical distribution were more sensitive to soil management regime than their community structure.

Several pre-emergent herbicides (azafenidin, oxyfluorfen, and imazaquin–pendimethalin mixture), used for weed control during the establishment of short-rotation willow plantings, were tested for their impact on population density, species richness, and community structure of predaceous (Gamasina) and saprophagous and (or) mycophagous (Oribatida) soil mites. The experimental control was hand-weeded (no herbicide). Two site preparation treatments were used: conventional (disked) and erosion controlled (no-till with cover crop of winter rye). The influence of herbicide application on non-target organisms (soil mites) cannot be generalized, with groups being differentially affected. Overall, Oribatida were most affected by herbicides. Among specific herbicides, azafenidin and oxyfluorfen had a negative effect on density and species richness of soil mites. The response of Oribatida and Gamasina to herbicides was species-specific. Two species of Oribatida ( Sellnickochthonius immaculatus (Forsslund) and Liochthonius lapponicus (Trägårdh)) declined significantly in all herbicide-treated plots. The cover crop residue had positive effect on both Oribatida and Gamasina; the negative effect of herbicides on Oribatida was greatly mitigated by cover crop. Herbicides appear to reduce mite diversity and alter community structure, but they do not always affect abundance. We speculate that the sensitivity of Oribatida to herbicides can reflect the indirect impacts of herbicides on soil microflora.

This study provides data on population and community ecology of Protura in native forests and Pinus radiata plantations in New Zealand. Abundance, age structure, sex ratios, biodiversity, and relationship with soil chemistry are discussed. Protura were significantly more abundant in pine plantations in comparison to native forests. Among native forests, Protura were most abundant under Southern beech (Nothofagus solandri). The abundance patterns may reflect the association between Protura and fungal communities in the soil. No correlation was found between soil organic matter, nitrogen, phosphorous, pH, cation exchange capacity, and the density of Protura. Protura assemblage composition was significantly related to forest type. New Zealand endemic species were associated with native forests; species with distribution outside New Zealand dominated in pine plantations. The distribution records within New Zealand were expanded for five species. The Protura fauna of New Zealand was increased to 18 sp...

This study explored the relationship between landscape-level factors (land use type) and the diversity of soil mites (Acari: Oribatida, Mesostigmata) at a within-site scale, using diversity measures including point diversity (local species diversity within a single sampling point), patterns of species turnover among the sampling points, and alpha diversity (total species richness in a habitat). The land use types included corn fields, intensive short-rotation forestry plantations, two types of abandoned agricultural fields, and hardwood forests. Land use type was identified as a significant factor influencing both small-scale (within individual soil cores) and site-scale diversity of Oribatida, which increased in the order “corn → willow → abandoned fields → forests”. There was no statistical relationship between land use type and abundance or diversity of Mesostigmata. Using a bootstrapping method to generate “random” communities, we found that all land use types had significantly more diverse patterns of species abundance than was expected by chance. On the other hand, the patterns of presence/absence of species were less diverse than expected by chance. Local site factors were significant in driving the patterns of diversity of soil mites at the site scale; land use type was less important. The overall structure of Oribatida and Mesostigmata assemblages was significantly related to land use type. We conclude that soil communities respond to land management on both local scales and habitat-wide scales.

Three new species of oribatid mites of the family Oppiidae (Oribatida, Oppioidea), belonging to the genera/subgenera Tripiloppia Hammer, 1968 and Lanceoppia (Baioppia) Luxton, 1985, are described from Central Otago, South Island, New Zealand. Tripiloppia frigida sp. nov. is morphologically similar to T. dalenii Hammer, 1968, but differs from the latter by the lanceolate bothridial setae, five pairs of genital setae, and trapezoid anterior notogastral protrusion. Tripiloppia alpina sp. nov. is morphologically similar to T. frigida sp. nov., but differs from the latter by the short, diagonal costulae, strong teeth in humeral regions, barbed lamellar setae, and interlamellar setae shorter than rostral setae. Lanceoppia (Baioppia) trapezoides sp. nov. is morphologically similar to L. (B.) moritzi Hammer, 1968, but differs from the latter by the larger body length, presence of notogastral setae c, and long interlamellar setae. The taxonomic status of the genus Autoppia GolosovaKarppinen, 1983 and systematic placement of Autoppia algicola GolosovaKarppinen, 1983 are discussed, resulting in the following taxonomic proposals: Tripiloppia Hammer, 1968 (=Autoppia GolosovaKarppinen, 1983 syn. nov.); Tripiloppia algicola (GolosovaKarppinen, 1983) comb. nov. The identification keys to known species of Tripiloppia and Lanceoppia (Baioppia) are given.

The effects of topographic variables (elevation above sea level, slope position, topographic (wetness) index, and global solar radiation) on mite abundances and on quantitative composition of Oribatida communities in soil and litter have been studied in six sites along a hill slope in a tropical lowland forest in the Bu Gia Map National Park, Southern Vietnam. A positive relationship existed between abundance and species richness of Oribatida in soil cores, and global solar radiation (W h m−2) which quantifies the total sun energy available to the local ecosystem. There was no significant relationship between abundance of Mesostigmata and topographic variables. The Oribatida community composition in soil and in litter was significantly different, with a large number of species unique to either litter or soil. The canonical correspondence analysis (CCA) showed that the topographic variables together explained 75 % (in litter) and 83 % (in soil) of the variation in Oribatida community structure. The species-topography relationship was globally significant in the litter, weaker in the soil; the eigenvalue of the CCA axis 1 (related to elevation and global solar radiation) was significant in both substrates. CCA ordinations identified groups of species associated with high landscape positions (hill crest, high elevation, high global solar radiation) versus species associated with low-lying landscape positions, where moisture tends to accumulate (hill footslope, low elevation, low solar radiation, high topographic index values). The importance of relief and geographical position for soil Oribatida is discussed.

Eucolaspis Sharp 1886 is a New Zealand native leaf beetle genus (Coleoptera: Chrysomelidae: Eumolpinae) with poorly described species and a complex taxonomy. Many economically important fruit crops are severely damaged by these beetles. Uncertain species taxonomy of Eucolaspis is leaving any biological research, as well as pest management, tenuous. We used morphometrics, mitochondrial DNA and male genitalia to study phylogenetic and geographic diversity of Eucolaspis in New Zealand. Freshly collected beetles from several locations across their distribution range, as well as identified voucher specimens from major museum collections were examined to test the current classification. We also considered phylogenetic relationships among New Zealand and global Eumolpinae (Coleoptera: Chyrosomelidae). We demonstrate that most of the morphological information used previously to define New Zealand Eucolaspis species is insufficient. At the same time, we show that a combination of morphological and genetic evidence supports the existence of just 3 mainland Eucolaspis lineages (putative species), and not 5 or 15, as previously reported. In addition, there may be another closely related lineage (putative species) on an offshore location (Three Kings Islands, NZ). The cladistic structure among the lineages, conferred through mitochondrial DNA data, was well supported by differences in male genitalia. We found that only a single species (lineage) infests fruit orchards in Hawke’s Bay region of New Zealand. Species-host plant associations vary among different regions.

We investigated the effects of several soil amendment materials, potentially useful for willow biomass crops, on the abundance, diversity, and community structure of free-living soil mites (Acari: Oribatida, Mesostigmata) in a 4-year replicated field experiment. Soil treatments included biosolids (lime-stabilized sewage sludge), chicken manure compost, urea fertilizer, black plastic mulch, and control. The predaceous Mesostigmata (40 spp.) responded differently to soil amendment treatments than did saprophagous and mycophagous Oribatida (28 spp.). The urea fertilizer had no persistent effect on mite assemblages. Plastic mulch did not affect Mesostigmata, but had a lasting detrimental effect on oribatid mites. Mesostigmatid mites benefited from application of biosolids, while Oribatida were most adversely affected by this treatment. When plastic mulch and biosolids were used together, the effect of biosolids predominated. Composted chicken manure supported abundant and diverse populations of both groups.

To address the question of how production of woody biomass crops on retired agricultural land will affect soil biodiversity, we investigated the effects of site preparation techniques associated with production of willow (Salix sp.) on the abundance, species diversity and community structure of two groups of mites (Oribatida and Gamasida). The effects of tillage, herbicide application, cover crop and mode of planting were evaluated in a 4 year-long replicated field experiment. Twenty-eight species of Oribatida and 35 species of Gamasida were represented in willow plantings. The predaceous Gamasida had more pronounced changes in abundance and diversity in response to the site preparation treatments than saprophagous and mycophagous Oribatida. Results indicated that (1) soil cultivation had negative effects on the abundance and diversity of soil mites during the first year of the experiment, later superceded by other factors; (2) the use or lack of tillage contributed to differences in mite community structure; and (3) following the initial disturbances, the abundance and diversity of soil mites increased in all treatments up to the end of the experiment. The success or failure of the willow crop and the changes in soil environments created by the different plant communities could explain the differences in soil mite populations among treatments best, especially 2 and 3 years after the beginning of the experiment.

A new species of oribatid mites of the genus Safrobates (Oribatida, Punctoribatidae) is described from the soil of alpine herbaceous snowbank of the Central Otago region in the South Island of New Zealand. Safrobates insignis sp. nov. differs from S. miniporus Mahunka, 1989 and S. gerdi Ermilov & Minor, 2016 in having penicillate subcapitular setae h, epimeral setae (except 1c) and aggenital setae, the presence of neotrichy on epimere I, four pairs of notogastral porose areas, six pairs of genital setae and tridactylous legs. Accessory information on Safrobates and the relevance of some morphological traits of the new species are discussed. A revised generic diagnosis is given, relationships of Safrobates, Macrogena and Magellozetes are discussed, and Magellozetes is transferred from Ceratozetidae to Punctoribatidae. An identification key to known species of Safrobates is provided.

Three new species of oribatid mites of the superfamily Oripodoidea (Acari, Oribatida) are described from the soil of alpine herbaceous snowbanks in the South Island of New Zealand. Scheloribates (Topobates) quindecim sp. nov. differs from all S. (Topobates) species by the presence of 15 pairs of notogastral setae (vs. 12–14 pairs). Paraphauloppia reducta sp. nov. differs from all Paraphauloppia species by the presence of one pair of genital setae (vs. 3–4 pairs). Reductobates perangustus sp. nov. differs from all Reductobates species by the elongate, narrow body. An identification key to known species of Reductobates is given.

Three new species of oribatid mites of the family Punctoribatidae (Acari, Oribatida) are described from alpine bogs of the Central Otago region in the South Island of New Zealand. Macrogena hexasetosa sp. nov. is morphologically most similar to M. brevisensilla Ermilov & Minor, 2015, however, it differs from the latter by larger body size, the presence of six pairs of genital setae, notogastral and ano-adanal setae of medium size, setiform rostral setae, narrower tutorial cusps, the absence of antero-ventral teeth on genua I, II and femora II, and by the absence of striae on the subcapitular mentum. Porallozetes badamdorji sp. nov. differs from the type species— P. dispar (Hammer, 1973)—by larger body length, the presence of interlamellar setae, short and clavate bothridial setae, anterior notogastral margin, notogastral setae of medium size, semi-oval dorsophragmata, and by the position of notogastral porose areas A2 posteriorly to A1 . Safrobates gerdi sp. nov. differs from the type species— S. miniporus Mahunka, 1989—by larger body size, the presence of setiform rostral setae, and by notogastral setae of medium length. Porallozetes and Safrobates are recorded in New Zealand for the first time. Generic diagnoses for Macrogena , Porallozetes and Safrobates are given.

Two new species of ceratozetoid oribatid mites (Acari, Oribatida, Ceratozetoidea) are described from alpine soils of the South Island of New Zealand. Magellozetes crassisetosus sp. nov. (Ceratozetidae) differs from known representatives of the genus ( M. antarcticus antarcticus (Michael, 1895), M. antarcticus traegardhi Subias 2010 and M. processus Hammer, 1962) by shorter interlamellar setae and minute tutorial cusps. Pedunculozetes ovatum sp. nov. (Chamobatidae) differs from known representatives of the genus ( P. andinus Hammer, 1962 and P. minutus Hammer, 1967) by minute interlamellar setae and short bothridial stalks. Updated generic diagnoses for Magellozetes and Pedunculozetes are provided.

Two new species of oribatid mites of the genus Dicrotegaeus (Oribatida, Cerocepheidae) are described from alpine soils of New Zealand. Dicrotegaeus mariehammerae sp. nov. shows straight lamellae distally, rostrum with a medial incision, the notogastral lateral tubercles developed, three pairs of adanal setae and triangular epimeral tubercles E4p. In Dicrotegaeus incurvus sp. nov. the anterior parts of the lamellae are curved medially, the rostrum has a strong longitudinal ridge, the notogastral lateral tubercles are absent, two pairs of adanal setae are present and the epimeral tubercles E4p are triangular. The type species, D. mirabilis Luxton, 1988 is the only other species in this genus and shows straight lamellae distally, the rostrum complex with a multiperforate projection, lateral tubercles present, two pairs of adanal setae and rectangular epimeral tubercles E4p. A new generic diagnosis and an identification key to all species of Dicrotegaeus are provided.

A new oribatid mite genus, Zealandozetes gen. nov. (Oribatida, Maudheimiidae), with type species Zealandozetes southensis sp. nov., is proposed and described based on adult and juvenile instars. It inhabits the soil under and around cushion-forming plants in the high-altitude alpine zone of two mountain ranges (the Pisa Range and The Remarkables) in the South Island of New Zealand. It is distinguished from species of Maudheimia by having pteromorphs reduced to pleural carinae, notogastral saccules, small pedotecta I, and both postanal porose area and Ah expressed as complex saccules. Juveniles are similar to those of Maudheimia, except the humeral organ of Z. southensis is cupule-like and gastronotic microsclerites are lacking. We give a revised diagnosis for Maudheimiidae and discuss both supportive and contradictory evidence for inclusion of Zealandozetes. Finally, we discuss endemism of Zealandozetes with reference to the knowledge of New Zealand biogeography and its oribatid fauna.

Collembola were collected from soil in the alpine belt (1600-1900 m a.s.l.) of the Southern Alps of New Zealand. A list of species found is provided. Austrodontella monticola sp. nov., the third species of a Odontellidae genus with a southern distribution is described. The other two species in the genus occur in southern Australia and in the Indian Ocean sector of the Subantarctic respectively. Notes on A. trispina (Womersley, 1935), the type species of the genus, are provided.

Although many believe that organic systems are sustainable as compared to conventional systems, there is a need to study the sustainability of organic systems per se. In this paper, sustainability of organic kiwifruit and apple production systems is modelled based on the concept of strong sustainability which gives utmost importance to environmental sustainability. Sustainability assessment is undertaken through analyses of key energy and material flows of the orchard system and their impacts on the environment. The proposed approach is based on two high level criteria for sustainability: energy efficiency and non-degradation of the environment. Five indicators which address the two criteria for sustainability are the energy ratio, carbon ratio, change in soil carbon level, soil nutrient balances and leaching of nitrogen. Sustainability indicators are estimated over one production year using two computer modelling tools, Overseer® and Stella®. Sustainability assessment indicates that the organic kiwifruit and apple systems are efficient in energy use and are a net carbon sink over a typical production year. The apple systems mined potassium from the soil which may be a threat to future yield and sustainability. Transition to sustainable farming systems implies reliance to a lesser extent on non-renewable energies and recognising the environmental bottom line.

Soil invertebrates play an important part in nutrient supply. It has been suggested that invertebrates have the greatest influence on nitrogen (N) availability in soils of low N fertility, and therefore invertebrates may be less important in pastoral systems with high N inputs. The influence of invertebrates on N cycling, and the fate of 15N-labelled plant litter, in a low- or high-N environment and in a soil with low or high bulk density were explored by the introduction of different elements of the invertebrate community in constructed soil ryegrass–white clover mesocosms. At high bulk density and low N, the N made available by invertebrates resulted in higher plant growth, without any increases in N losses to the environment. At high N, where pasture growth was not limited by N, the N made available by invertebrates increased both herbage N% and the amount of N in leachate. More of the 15N-labelled plant litter decomposed in high-N than low-N mesocosms. Invertebrates increased the plant uptake of surface-applied 15N plant litter. The influence of invertebrates was dependent on bulk density, suggesting that invertebrates in compacted soils improved soil structure and N availability. This mesocosm study highlights the important role of invertebrates in N supply across a range of soil conditions.

It is often difficult to compare the effects of land use on soil invertebrates across different soil types, as management practices are often adjusted to compensate for soil differences. A mosaic of two contrasting and co-occurring soils offered a unique opportunity to examine the influence of common management practices on soil invertebrates (macrofauna, mesofauna, and nematodes). Treatments established on a well-structured Andosol soil and co-occurring poorly structured Gleysol included a legume-based pasture grazed at 2.3 cows/ha and nitrogen (N) fertilised pastures grazed at 3 and 3.8 cows/ha, with the 3.8 cows/ha treatment also receiving maize supplementation. Low abundance (