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In light of climate change, zero carbon refurbishment for existing buildings is imperative for maximising carbon emission reductions. Due to the increasing complexity of reducing carbon emissions for existing buildings, there is a need for a more collaborative and integrative approach. Extensive research has shown the importance, benefits, and challenges of collaboration and integration in implementing sustainable buildings. However, little attention has been paid to investigating collaboration and integration in refurbishment projects that focus on reducing life cycle carbon emissions. This paper explores the collaboration and integration in the decision-making process towards zero carbon refurbishment by examining three real-life case studies in New Zealand. The findings resulted from an interactive cross-case analysis using replication logic within and among cases. Empirically, the study emphasises the importance of (1) organisational commitment and compatibility of team members, (2) the timely involvement of key stakeholders, (3) the highest level of integration in the design process, and (4) a centralised and integrated information system. The paper also divulges the current practices and challenges faced in the integration process, where lessons learnt are identified for future refurbishment projects. A collaboration and integration framework towards successfully delivering building projects towards zero carbon is proposed. The research implications may assist the real-world uptake of the zero‑carbon refurbishment approach by promoting effective collaboration and integration. • An interactive analysis between theoretical propositions and cross-case synthesis • Divulging challenges and lessons learnt in the collaboration and integration process • Proposing a collaboration and integration framework towards zero carbon refurbishment • Promoting an effective collaboration to assist the real-world uptake of zero-carbon refurbishment [ABSTRACT FROM AUTHOR]

The voluntary carbon market (VCM) is a relatively mature field where institutions have become firmly established. This empirical paper explores findings obtained from interviewing key actors within the VCM in New Zealand, at a time when the organizational field was beginning to emerge (2010/2011). Fourteen semi-structured interviews were carried out with managers and decision-makers at 13 organizations, representing a cross-section of leaders in the field at the time. Participants were investigated regarding their cognitions as well as their operational activities and interactions with the range of actors in the field, and how these evolved over time. Case studies of the wine industry, the taxi industry and the carbon services industry are presented. Findings identify a number of early successes, including endeavors which focused on promoting market integrity through infrastructure and knowledge sharing amongst participants, which influenced others to shift behavior around climate change mitigation in general. Setbacks are evident as well, with the primary setback characterized as market stagnation: buyers and sellers drifting away from the market. Communication challenges, low certification recognition, risk of greenwash exposure, policy uncertainty, the global financial crisis and general disenchantment with the carbon market were listed as some of the causes. [ABSTRACT FROM AUTHOR]

Purpose: This study examines how carbon tools, including carbon accounting and management tools, can be created, used, modified and linked with other traditional management controls to materialise and effectuate organisations' response strategies to multiple interacting logics in carbon management and the role of sustainability managers in these processes. Design/methodology/approach: This study utilises the construct of accounting toolmaking, which refers to practices of adopting, adjusting and reconfiguring accounting tools to unfold how carbon tools are used as means to materialise responses to multiple interacting carbon management logics. It embraces a field study approach, whereby 38 sustainability managers and staff from 30 organisations in New Zealand were interviewed. Findings: This study finds that carbon toolmaking is an important means to materialise and effectuate organisations' response strategies to multiple interacting carbon management logics. Four response strategies are identified: separation, selective coupling, combination and hybridisation. Adopting activity involves considering the additionality, detailing, localising and cascading of carbon measures and targets and their linkage to the broader carbon management programme. In adjusting carbon tools, organisations adapt the frequency and orientation of carbon reporting, intensity of carbon monitoring and breadth of carbon information sharing. Through focusing on either procedural sequencing, assimilating, equating or integrating, toolmaking reconfigures the relationship between carbon tools and traditional management control systems. Together, these three toolmaking activities can be configured differently to construct carbon tools that are fit for purpose for each response strategy. These activities also enact certain roles on sustainability managers in the process of representing, communicating and/or transferring carbon information knowledge, which also facilitate different response strategies. Practical implications: The study demonstrates the various carbon toolmaking practices that allow organisations to handle the multiple interacting logics in carbon management. The findings provide suggestions for organisations on how to adopt, adjust and reconfigure carbon tools to better embed the ecological logic in organisations' strategies and operations. Originality/value: The authors identify how carbon toolmaking materialises and effectuates organisations' responses to multiple interacting logics in carbon management. [ABSTRACT FROM AUTHOR]

Concerns about climate change and water quality make it necessary to have a better understanding of the cycling of carbon (C) and nitrogen (N) within landscapes. In New Zealand, pastoral farming on hill country is a major land use, and there is little information available at a landscape level on the cycling of C and N within these systems, particularly the impacts of land use intensification. Published information on the individual components of C and N cycles in hill country pastoral systems was used to construct simple C and N models for two notional hill country paddocks with contrasting amounts of annual net herbage accumulation (NHA). These simple models of C and N cycling were used to explore the potential impacts of intensification on soil C and N pools. The C and N models constructed illustrate that both the C and N cycles in hill country pastoral farming are characterised by large fluxes in and out of the system and relatively small annual accumulations or depletions of their respective soil pools. The mechanisms by which these inward and outward fluxes are generated differ greatly between C and N. Most of the C cycling through the soil/plant/animal system in a year is sourced from the atmosphere through photosynthesis in that same year and the annual quantity of C ingested by grazing animals is only approximately 25% of that fixed annually. In contrast, the annual quantity of N ingested by grazing animals is 300–400% of that added to the system annually by fixation, and most of this ingested N (>80%) is returned to the soil in animal excreta. This contrasts with <25% of ingested C returned in animal excreta. Grazing animals, with their propensity to exhibit camping behaviour, are therefore much more influential in the spatial redistribution of N than C in hill country pastures. The simple C and N models presented in this paper indicate that while land use intensification results in increased inputs of both C and N to the soil, intensification is also likely to result in increased losses of C and N from the soil pool. Which of these processes dominates in a given situation determines whether intensification will result in an increase or decrease of soil C and N. Based on a simple C model, we postulate that if intensification increases NHA by one unit there is likely to be an increase in soil C unless at the same time increased grazing pressure results in at least a three-unit increase in dry matter eaten/harvested. [ABSTRACT FROM AUTHOR]

In the light of climate change, the drive for zero carbon buildings is known as one response to reduce greenhouse gas emissions. Within New Zealand, research on climate change mitigation and environmental impacts of buildings has received renewed attention. However, there has been no detailed investigation of zero carbon building practices. This paper undertakes an exploratory study through the use of semi-structured interviews with government representatives and construction industry experts to examine how the New Zealand construction industry plans and implements zero carbon buildings. The results show that New Zealand's construction industry is in the early stage of transiting to a net-zero carbon built environment. Key actions to date are focused on devising a way for the industry to develop and deliver zero carbon building projects. Central and local governments play a leading role in driving zero carbon initiatives. Leading construction firms intend to maximise the carbon reduction in building projects by developing a roadmap to achieve the carbon target by 2050 and rethinking the way of designing and constructing buildings. The research results provide an insight into the initial practices and policy implications for the uptake of zero carbon buildings in Aotearoa New Zealand. [ABSTRACT FROM AUTHOR]

This paper analyses the Energy Return on Energy Invested (EROI) and Energy Return on Carbon Emissions (EROC) of current wind energy farms in New Zealand. The weighted average EROI for a New Zealand wind energy farm over a 20 year life span is 34.3, with the highest achieving 57.7, while the lowest is 6.5. These values are higher than wind energy farms in Europe and America, which average about 20, and higher than many other electricity generation methods reported in the literature with hydropower being the main exception. The above-average capacity factor of New Zealand wind energy farms is the primary reason for the higher EROI values. The average EROC value for New Zealand's existing wind energy farms is 477 GJ/t CO 2 -e, which is 56 times the EROC of a combined cycle natural gas power station. The substantial range of EROI values are chiefly driven by two factors: (1) wind speed profile for a given site and (2) the blade diameter of the turbine, where greater values are better. The main drawback of wind energy is variability causing reliability issues and needing hydro power as a renewable buffer to keep emissions low. [ABSTRACT FROM AUTHOR]

This article examines the drivers and process of change in carbon controls within a New Zealand electricity utility, using a meta‐triangulation approach that employs three theoretical perspectives (transactional cost economics, the resource‐based view and new institutional sociology). Results suggest three main objectives motivate carbon controls: cost control, competitiveness and legitimacy. Multiple environmental demands and expectations were met by focusing controls on a particular stakeholder group or objective. Further, the research identifies the conditions under which carbon controls are integrated and institutionalised within an organisational management control system. The theoretical interplay provides insight into inter‐relationships between institutional environments, organisational resources and carbon transactional characteristics. [ABSTRACT FROM AUTHOR]

Abstract: The transition of land between forest and grassland has important implications for greenhouse gas emissions and removals. In this paper, we use New Zealand as a case study to comprehensively assess, compare and quantify the net climate change impact of shifting land use between temperate forest and grassland. Forests store large amounts of carbon in their biomass, whereas grasslands contain relatively little biomass carbon. These biomass changes tend to dominate the carbon balance under land-use change. Soil carbon stocks usually do not change much after deforestation unless subsequent erosion occurs, but some soil carbon is often lost when grasslands are reforested with exotic plantations. Forest soils usually release little nitrous oxide or methane and can even oxidise small amounts of methane. Grasslands, on the other hand, can release a large amount of nitrous oxide, which may be further increased with fertilisation, and is higher for cattle- than sheep-grazed systems. Grazing animals increase emissions because the concentrated forms of nitrogen in their excreta allow it to escape from the system. Ruminant animals can also emit large amounts of methane. Land cover change in addition has direct radiative effects through the amount of solar radiation that is either absorbed by vegetated surfaces or reflected back into space. As forests typically absorb more radiation than grasslands, this slightly negates the greenhouse consequences of changes in carbon storage, and methane and nitrous oxide emissions under land-use change. [Copyright &y& Elsevier]

Abstract: Carbon Emissions Pinch Analysis (CEPA) is a recent extension of traditional thermal and mass pinch analysis to the area of emissions targeting and planning on a macro-scale (i.e. economy wide). This paper presents an extension to the current methodology that accounts for increased demand and a carbon pinch analysis of the New Zealand electricity industry while illustrating some of the issues with realising meaningful emissions reductions. The current large proportion of renewable generation (67% in 2007) complicates extensive reduction of carbon emissions from electricity generation. The largest growth in renewable generation is expected to come from geothermal generation followed by wind and hydro. A four fold increase in geothermal generation capacity is needed in addition to large amounts of new wind generation to reduce emissions to around 1990 levels and also meet projected demand. The expected expansion of geothermal generation in New Zealand raises issues of GHG emissions from the geothermal fields. The emissions factors between fields can vary by almost two orders of magnitude making predictions of total emissions highly site specific. [Copyright &y& Elsevier]

This paper describes results from a study of the effects of first rotation radiata pine (Pinus radiata) on major organic constituents (carbon, nitrogen and sulfur) in hill country pasture soils in New Zealand. Soil properties were compared under 17–19-year-old radiata pine and adjacent pasture at four sites on the boundary of a 9000-ha forest. No fertiliser had been applied to either forest or pasture areas since tree establishment, and the pasture sites were either ungrazed or lightly grazed. Differences between sites included soil type (influenced mainly by drainage) and soil fertility (influenced mainly by fertiliser history prior to afforestation). Concentrations of organic carbon and nitrogen were 15–43% lower in soil to a 12–18-cm depth under trees compared with pasture at three sites. On the other hand, total (organic) sulfur was significantly lower (19–44%) in topsoil under trees compared with pasture at all sites, while concentrations of plant available sulfate–sulfur were consistently and significantly higher in soil to 30-cm depth under trees compared with pasture. These findings confirmed that afforestation of hill country pasture soils resulted in net mineralization of soil organic sulfur in addition to organic carbon and nitrogen. [Copyright &y& Elsevier]

The article reports on the sixth Australia-New Zealand Climate Change and Business Conference held in 2010. A paper suggested that Australia can learn from New Zealand's carbon pricing, while New Zealand can adopt how the other country implements complementary measures, both regulatory and incentive. Andy Pitman of the University of New South Wales Climate Change Research Center talked about the impact of climate change. Information on the 7th Australia-New Zealand Climate Change & Business Conference to be hosted by New Zealand on 2011 is also included.

We describe the change in operational instrument for the routine measurement of column-averaged dry-air mole fraction of several greenhouse gases (denoted Xgas) at the Lauder Total Carbon Column Observing Network (TCCON) site and the steps taken to demonstrate comparability between the two observation systems following a systematic methodology. Further, we intercompare retrieved Xgas values during an intensive intercomparison period during October and November 2018, when both instruments were performing optimally, and on subsequent, less frequent occasions. The average difference between the two observing systems was found to be well below the expected level of uncertainty for TCCON retrievals for all compared species. In the case of XCO2 the average difference was 0.0264±0.0465 % (0.11±0.19 µ mol mol -1). [ABSTRACT FROM AUTHOR]

Blue carbon is increasingly being considered in global carbon budgets; however, there is poor understanding of how carbon stocks vary within mangrove forests with heterogeneous growth forms and in areas where mangroves are showing rapid changes in distribution. Here, field measurements and LiDAR data were used to estimate aboveground carbon stocks and economic benefits of Avicennia marina in the Auckland Region, New Zealand, where the mangrove area has increased at an annual rate of 3.2% since 1940. Multiple allometric equations were explored to determine best fits for different growth forms (tall and dwarf mangroves) that minimised uncertainty in conversions of tree size to aboveground carbon stock estimates. Across the Auckland Region, the mean total aboveground carbon stock (including trees, seedling, pneumatophores and woody debris) was 40.2 Mg C ha−1 with over 75% contained in tree biomass. Total aboveground carbon stocks varied considerably between mangrove growth form (tall and dwarf mangroves) and hydrodynamic conditions (estuarine, riverine and delta mangroves). Total aboveground carbon storage across the Auckland Region amounted to 384,451 Mg C with an economic value of US$ 70 million. This study demonstrates that LiDAR data can be used to produce reliable and high-resolution tree carbon stock estimates in estuaries characterised by spatially variable distributions of dwarf mangroves. These estimates are critical for the incorporation of mangroves into national blue carbon accounting schemes. [ABSTRACT FROM AUTHOR]

Our study examines the drivers of tight budgetary control in carbon management in the context of climate change regulation. Using the setting of New Zealand Emissions Trading Scheme (ETS), our study explores how firms manage their carbon performance using carbon‐focused budgetary control. Based on a survey data from New Zealand firms, including both those with and those without an ETS compliance obligations, our results suggest that economic and regulatory environmental pressures, the level of proactiveness of emissions management strategy, the level of integration of carbon issues in strategic and operational processes and the perceived importance of carbon issues are the significant drivers of tight carbon‐focused budgetary control. [ABSTRACT FROM AUTHOR]

Background: Forests are a key component of the global carbon cycle, and research is needed into the effects of human-driven and natural processes on their carbon pools. Airborne laser scanning (ALS) produces detailed 3D maps of forest canopy structure from which aboveground carbon density can be estimated. Working with a ALS dataset collected over the 8049-km Wellington Region of New Zealand we create maps of indigenous forest carbon and evaluate the influence of wind by examining how carbon storage varies with aspect. Storms flowing from the west are a common cause of disturbance in this region, and we hypothesised that west-facing forests exposed to these winds would be shorter than those in sheltered east-facing sites. Methods: The aboveground carbon density of 31 forest inventory plots located within the ALS survey region were used to develop estimation models relating carbon density to ALS information. Power-law models using rasters of top-of-the-canopy height were compared with models using tree-level information extracted from the ALS dataset. A forest carbon map with spatial resolution of 25 m was generated from ALS maps of forest height and the estimation models. The map was used to evaluate the influences of wind on forests. Results: Power-law models were slightly less accurate than tree-centric models (RMSE 35% vs 32%) but were selected for map generation for computational efficiency. The carbon map comprised 4.5 million natural forest pixels within which canopy height had been measured by ALS, providing an unprecedented dataset with which to examine drivers of carbon density. Forests facing in the direction of westerly storms stored less carbon, as hypothesised. They had much greater above-ground carbon density for a given height than any of 14 tropical forests previously analysed by the same approach, and had exceptionally high basal areas for their height. We speculate that strong winds have kept forests short without impeding basal area growth. Conclusion: Simple estimation models based on top-of-the canopy height are almost as accurate as state-of-the-art tree-centric approaches, which require more computing power. High-resolution carbon maps produced by ALS provide powerful datasets for evaluating the environmental drivers of forest structure, such as wind. [ABSTRACT FROM AUTHOR]

Soil organic matter is a potential sink of atmospheric carbon (C) and critical for maintaining soil quality. We reviewed New Zealand studies of soil C changes after conversion from woody vegetation to pasture, and under long-term pasture. Soil C increased by about 13.7 t C ha−1to a new steady state when forests were initially converted to pasture. In the last 3–4 decades, resampling of soil profiles demonstrated that under long-term pasture on flat land, soil C had subsequently declined for allophanic, gley and organic soils by 0.54, 0.32 and 2.9 t C ha−1 y−1, respectively, and soil C had not changed in the remainder of sampled soil orders. For the same time period, pasture soils on stable midslopes of hill country gained 0.6 t C ha−1 y−1. Whether these changes are ongoing is not known, except for the organic soils where losses will continue so long as they are drained. Phosphorus fertiliser application did not change C stocks. Irrigation decreased carbon by 7 t C ha−1. Carbon losses during pasture renewal ranged between 0.8 and 4.1 t C ha−1. Some evidence suggests tussock grasslands can gain C when fertilised and not overgrazed. When combined to the national scale, different data sets suggest either no change or a gain of C, but with large uncertainties. We highlight key land-use practices and soil orders that require further information of soil C stock changes and advocate for a better understanding of underpinning reasons for changes in soil C. [ABSTRACT FROM AUTHOR]

This study examines a case study of the Rarakau Rainforest Conservation Project on Māori-owned land in western Southland - New Zealand's first and only REDD+ project. It explores the potential for REDD+ projects on Māori land throughout the country. Key findings show that REDD+ is technically feasible in New Zealand, but commercially dependent on (currently low) demand in the domestic retail carbon offset and 'corporate social responsibility' market. Market research suggests that there is sufficient demand to cater to the needs of a small number of REDD+ projects, but insufficient demand to roll out a nation-wide scheme. [ABSTRACT FROM AUTHOR]

To meet international greenhouse gas reporting obligations, New Zealand must report on carbon stocks in forests established after 1989 (post-1989 forest). Although predominately comprised of planted forest, post-1989 forest also contains a component of natural vegetation amounting to less than 10% by area. New Zealand undertook a national inventory of this natural stratum of post-1989 forest to provide estimates of carbon stocks and stock change in woody species over the first commitment period (2008-2012) of the Kyoto Protocol. Plots were installed on a 4-km grid, and the basal diameters and heights of trees and shrubs were measured for the first time from November 2012, to March 2013. Carbon stocks in 2012 were calculated using allometric functions developed from biomass samples from each site. Basal disc samples provided data on diameter increment and shrub and tree age annually from 1990 to 2012. These were used to predict carbon stocks per ha for individual plots in 2008 and to provide annual predictions by pool back to 1990. Carbon stocks summed across live and dead biomass pools (excluding soil) averaged 3.04, 16.70 and 28.73 t C/ha in 1990, 2008 and 2012, respectively. The disposition by pool was 2.25, 12.54 and 21.84 t C/ha in aboveground biomass, 0.56, 3.13 and 5.46 t C/ha in belowground biomass (using a root/shoot ratio of 0.25), 0.03, 0.17 and 0.23 t C/ha in deadwood, and 0.18, 0.86 and 1.21 t C/ha in litter in 1990, 2008 and 2012, respectively. [ABSTRACT FROM AUTHOR]

The Macraes orogenic gold deposit is hosted by a graphitic micaceous schist containing auriferous porphyroblastic sulphides. The host rock resembles zones of unmineralised micaceous graphitic pyritic schists, derived from argillaceous protoliths, that occur locally in background pelitic Otago Schist metasediments. This study was aimed at determining the relationship between these similar rock types, and whether the relationship had implications for ore formation. Argillites in the protolith turbidites of the Otago Schist metamorphic belt contain minor amounts of detrital organic matter (<0.1 wt.%) and diagenetic pyrite (<0.3 wt.% S). The detrital organic carbon was mobilised by metamorphic-hydrothermal fluids and redeposited as graphite in low-grade metaturbidites (pumpellyite-actinolite and greenschist facies). This carbon mobility occurred through >50 million years of evolution of the metamorphic belt, from development of sheared argillite in the Jurassic, to postmetamorphic ductile extension in the Cretaceous. Introduced graphite is structurally controlled and occurs with metamorphic muscovite and chlorite as veins and slicken-sided shears, with some veins having >50% noncarbonate carbon. Graphitic foliation seams in low-grade micaceous schist and metamorphic quartz veins contain equant graphite porphyroblasts up to 2 mm across that are composed of crystallographically homogeneous graphite crystals. Graphite reflectance is anisotropic and ranges from ~1% to ~8% (green light). Texturally similar porphyroblastic pyrite has grown in micaceous schist (up to 10 wt.% S), metamorphic quartz veins and associated muscovite-rich shears. These pyritic schists are weakly enriched in arsenic (up to 60 ppm). The low-grade metamorphic mobility and concentration of graphite in micaceous schists is interpreted to be a precursor process that structurally and geochemically prepared parts of the Otago Schist belt for later (more restricted) gold mineralisation. Economic amounts of gold, and associated arsenic, were subsequently introduced to carbonaceous sulphidic schists in the Macraes gold deposit by a separate metamorphic fluid derived from high-grade metaturbidites. Fluid flow at all stages in these processes occurred at metamorphic rates (mm/year), and fluids were broadly in equilibrium with the rocks through which they were passing. [ABSTRACT FROM AUTHOR]

Grassland net primary productivity, carbon (C) allocation to roots, root production and subsequent turnover time in grazed pastures have significant implications for modelling landuse effects on global carbon dynamics. The objective of this work, using the decline of assimilated 13C, was to quantify C allocation to roots, root production and turnover time in response to long-term fertiliser and irrigation treatments. The treatments on the pastures on a long-term research site at Winchmore, Canterbury, New Zealand were 0 or 375 kg ha−1 y−1 superphosphate under irrigation and, on a nearby irrigation experiment, unirrigated or irrigated (with fertilisation of 250 kg ha−1 y−1 superphosphate) when the soil water content fell to 20% w/w (50% available moisture). The pasture treatments were pulse-labelled using 13CO2 within portable gas-tight enclosures. Separate micro-plots were 13CO2 pulse-labelled in late spring, summer and autumn. Below ground net primary production (206 g C m−2 y−1) was similar in unfertilised, unirrigated, fertilised and irrigated pastures, despite marked differences in above ground production. Unfertilised/irrigated and unirrigated/fertilised treatments had greater root biomass, root C allocation and longer root turnover time (1.9 y and 2.0 y, respectively) than fertilised and irrigated treatments (1.3 y). These root turnover times appeared to be consistent with the improved substrate quality attributed to the species found in the irrigated and fertilised treatments. [ABSTRACT FROM AUTHOR]

Methanotrophs use methane (CH4) as a carbon source. They are particularly active in temperate forest soils. However, the rate of change of CH4 oxidation in soil with afforestation or reforestation is poorly understood. Here, soil CH4 oxidation was examined in New Zealand volcanic soils under regenerating native forests following burning, and in a mature native forest. Results were compared with data for pasture to pine land-use change at nearby sites. We show that following soil disturbance, as little as 47 years may be needed for development of a stable methanotrophic community similar to that in the undisturbed native forest soil. Corresponding soil CH4-oxidation rates in the regenerating forest soil have the potential to reach those of the mature forest, but climo-edaphic fators appear limiting. The observed changes in CH4-oxidation rate were directly linked to a prior shift in methanotrophic communities, which suggests microbial control of the terrestrial CH4 flux and identifies the need to account for this response to afforestation and reforestation in global prediction of CH4 emission. [ABSTRACT FROM AUTHOR]

The OVERSEER® nutrient budgets model is increasingly being used by farmers and regional councils to assess N and P inputs and outputs from farms. There are, however, few data for low fertility and nigh fertility soils in hill country grazed by sheep. Two farmlets at AgResearch Ballantrae, near Woodville, with no-fertiliser (NF) and 375 kg ha-1 year-1 superphosphate high fertiliser (HF) added since 1980, were used to quantitatively estimate N and P cycles under sheep-grazed pastures at two stages of N saturation. We present data on soils, N and P leaching, and uptake for a trial in which treatments to both farmlets were (a) control, (b) herbicide applied (for broadleaves), and (c) 300 kg N ha-1 added annually. Trial plots were located on 3-9° slopes in each farmlet. In winter, seepage zones in mini-catchments in each farmlet generated waters that allowed us to follow nutrient movement from soils to waters. Winter 2006 had above average rainfall, with one intense storm where surface runoff was observed. During other storms, water perched at about 300 mm depth in the subsoil, and moved to seeps solely by subsurface runoff. Mean nitrate-N concentration in drainage at HF was nighest in 2006, as were surface and subsurface runoff, giving a calculated annual loss of nitrate-N of 44 kg N ha-1, compared with 20 kg N ha-1 in 2005 and 27 kg N ha-1 in 2007. At NF, the losses ranged from 1-2 kg N ha-1. P losses increased considerably during surface runoff. Mean annual losses in drainage for HF and NF, respectively, were 1.0 and 0.3 kg ha-1 for dissolved reactive R 8 and 4 kg ha-1 for dissolved organic N (DON), and 121 and 228 kg ha-1 for dissolved organic C (DOC). The DOC/DON ratio was lower at HF (16) than at NF (54). In the plots with 300 kg N added, soil N status increased at NF and losses increased from 2 to 14 kg N ha-1 year-1 at 200 mm depth; losses at HF were over 80 kg N ha-1 year-1. This suggests soils on these slopes in the HF farmlet can become saturated with N and no longer retain N; soils in the NF farmlet appeared to retain N fertiliser initially, but by years 2 and 3 they appeared to become saturated with N. Gaseous emissions of ammonia, NOx and N2 would also increase as pastures and soils become enriched with N. The OVERSEER® nutrient budgets model gave good predictions of N in waters but underestimated P losses. The pathways of both gaseous losses and immobilisation of N in soils require further study to better quantify the N cycles. [ABSTRACT FROM AUTHOR]

Dissolved organic nitrogen (DON) and dissolved organic carbon (DOC) in soils are increasingly recognized as important components of nutrient cycling and biological processes in soil-plant ecosystems. The aims of this study were to: (i) quantify the pools of DON and DOC in a range of New Zealand pastoral soils; (ii) compare the effects of land use changes on these pools; and (iii) examine the seasonal variability associated with these two components of dissolved organic matter. Soil samples (0–7.5 cm depth) from 93 pastoral sites located in Northland, Waikato, Bay of Plenty and Otago/Southland, New Zealand, were collected in autumn. Adjacent sites under long-term arable cropping or native vegetation and forestry land use were also sampled at the same time to estimate the impacts of different land use on DON and DOC in these soils. Twelve dairy and 12 sheep and or beef pastures were sampled in winter, spring, summer and autumn for a 2-year period to study the seasonal fluctuations of DON and DOC. A field incubation study was also carried out in a grazed pasture to examine fluctuations in the concentrations of and and DON levels in soil. Other soil biological properties, such as microbial biomass-C, biomass-N and mineralizable N, were also measured. Pastoral soils contained the greatest amounts of DON (13–93 mg N kg−1 soil, equivalent to 8–55 kg N ha−1) and DOC (73–718 mg C kg−1 soil, equivalent to 44–431 kg C ha−1), followed by cropping and native vegetation and forestry soils. The DON concentration in soils was found to be more seasonally variable than DOC. There was approximately 80% fluctuation in the concentration of DON in winter from the annual mean concentration of DON, while DOC fluctuated between 23 and 28% at the dairy and the sheep and beef monitoring sites. Similar fluctuations in the concentrations of DON were also observed in the field incubation studies. These results indicate that DON is a dynamic pool of N in soils. There was a strong and significant positive correlation between DON and DOC in pastoral soils ( r = 0.71, P < 0.01). There were also significant positive correlations between DON and total soil C ( r = 0.59, P < 0.01), total soil N ( r = 0.62, P < 0.01) and mineralizable N ( r = 0.47, P < 0.01). The rather poor correlations between total soil C and N with DOC and DON, suggest other biogeochemical processes may be influencing concentrations of DOC and DON in these soils. Given the size of DON and DOC pools in the pastoral soils, we suggest that these pools of C and N should be taken into account when assessing the impact of pastoral land use on soil C and N enrichment of surface and groundwater. [ABSTRACT FROM AUTHOR]

Focuses on a study which developed the national Carbon Monitoring System (CMS) to quantify the baseline carbon stock of soil and the changes associated with land-use change in New Zealand. Description and refinement of soil CMS; Methodology of the study; Results and discussion.

Summary • Contemporary studies of stable carbon isotope values (δ 13 C) from leaves in the canopies of mature forest indicate that reduced irradiance and respired CO 2 might bias palaeoenvironmental reconstructions developed using the 13 C content of unsorted plant material formed within comparable ancient environments. • Here, we investigated whether any simple morphological and/or chemical characteristics could identify the position of the leaf within a canopy of the evergreen mountain beech ( Nothofagus solandri var. cliffortiodes ). • Leaf mass per unit area, carbon content and δ 13 C values of both bulk and lignin components of the leaves increased exponentially from the ground up through the canopy. Nitrogen, remobilized before death, was unsuitable as an indicator of canopy position. Leaf mass per unit area on the forest floor indicated that leaves from the sunlit part comprised approximately 30% of the fallen leaves; leaves originating from the upper canopy made up the remaining litter. • Application of leaf mass per unit area to a 22 000-yr-old sequence dominated by mountain beech leaves from Mount George (New Zealand), demonstrated that this signal was preserved in the fossil record. Sunlit leaf material can be successfully differentiated from that originating deeper within the palaeo-canopy, thereby allowing robust δ 13 C analyses for palaeoenvironmental reconstruction. [ABSTRACT FROM AUTHOR]