19366 research outputs found
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What is a hazard and do we need to protect it? Greater Christchurch case study on the tension between the National Policy Statement for Highly Productive Land 2022 and National Environmental Standard for Assessing and Managing Contaminants in Soil to Protect Human Health 2011 : A dissertation submitted in partial fulfilment of the requirements for the Degree of Master in Planning at Lincoln University
No full textNew Zealand has a long history of complex agricultural processes threatened by erosion, urbanization and contamination. The recent National Policy Statement for the Protection of Highly Productive Land (NPS-HPL) 2022 aims to safeguard the land for food or primary production. However, certain agriculture-related activities are identified as hazardous to the land and could result in contamination. The purpose of my research is to identify if there is any interaction between the new and existing national standards in addressing potential contamination. The NPS-HPL seems to contain matters it may not have intended and could affect the way farming and agricultural activities are approved or carried out on productive land.
This research investigates the interpretations of soil protection and agrochemicals in the Greater Christchurch area. Quantitative methods inform qualitative methods to understand how these tensions are addressed in local government policies and plans, which are required to give effect to the national directives.
The Greater Christchurch regulatory bodies have removed many provisions from their district plans for hazardous substances but note the interactions between agrochemicals and soil contamination. Accumulative non-point deposition of persistent organic pollutants from agricultural activities might affect future generations. The data suggests an interaction between the use of agrochemicals and soil contamination. However, it is undetermined how long this would take for soil productivity to be adversely affected. This research discusses the effect of sustainability, avoiding adverse effects, and contamination highlighted in the NPS-HPL. Possible interpretation may require councils and local governments to take further action in managing hazardous agricultural activities. Whether the NPS-HPL gives clarity in a time of fast-paced legislation or allows the independent local government authorities to make their own decisions for their region is yet to be seen. Identifying if agrichemicals are hazardous to highly productive land and if independent levels need to be set for their continued use can be expected to be a challenge for policymakers
Local climate modulates the development of soil nematode communities after glacier retreat
No full textThe worldwide retreat of glaciers is causing a faster than ever increase in ice‐free areas that are leading to the emergence of new ecosystems. Understanding the dynamics of these environments is critical to predicting the consequences of climate change on mountains and at high latitudes. Climatic differences between regions of the world could modulate the emergence of biodiversity and functionality after glacier retreat, yet global tests of this hypothesis are lacking. Nematodes are the most abundant soil animals, with keystone roles in ecosystem functioning, but the lack of global‐scale studies limits our understanding of how the taxonomic and functional diversity of nematodes changes during the colonization of proglacial landscapes. We used environmental DNA metabarcoding to characterize nematode communities of 48 glacier forelands from five continents. We assessed how different facets of biodiversity change with the age of deglaciated terrains and tested the hypothesis that colonization patterns are different across forelands with different climatic conditions. Nematodes colonized ice‐free areas almost immediately. Both taxonomic and functional richness quickly increased over time, but the increase in nematode diversity was modulated by climate, so that colonization started earlier in forelands with mild summer temperatures. Colder forelands initially hosted poor communities, but the colonization rate then accelerated, eventually leveling biodiversity differences between climatic regimes in the long term. Immediately after glacier retreat, communities were dominated by colonizer taxa with short generation time and r‐ecological strategy but community composition shifted through time, with increased frequency of more persister taxa with K‐ecological strategy. These changes mostly occurred through the addition of new traits instead of their replacement during succession. The effects of local climate on nematode colonization led to heterogeneous but predictable patterns around the world that likely affect soil communities and overall ecosystem development
Economic Analysis and Policy
No full textBetter access to domestic and international markets allows rural farmers to sell their products at higher prices, motivating them to increase the quantity, quality, and diversity of the goods they produce and sell more. Reliable market access is also beneficial to regional income growth, food security, and poverty and hunger alleviation. Despite these significant benefits, smallholder farmers’ market access has been constrained by a wide range of factors, such as remote locations, information asymmetry, high transaction costs, and the lack of business skills. These issues are more common in developing and emerging countries.With this special issue, we seek to comprehensively understand the linkages between farmers and markets in Asian countries. Contributions from other countries are also equally welcome. We aim to shed light on the barriers to farmers’ market access, devise appropriate solutions, and widely explore the impacts of market access. The findings are expected to provide significant insights for policymakers to design appropriate policy instruments that improve smallholder farmers’ market access and promote sustainable agricultural, rural, and social development
Estimating U.S. housing price network connectedness: Evidence from dynamic Elastic Net, Lasso, and Ridge vector autoregressive models
No full textThis paper investigates the dynamic connectedness of random shocks to housing prices between the 50 U.S. states and the District of Columbia. The paper implements a standard vector autoregressive (VAR) model as well as three VAR models with shrinkage effects — Elastic Net, Lasso, and Ridge VAR models. The transmission of real housing return shocks on a regional basis flows from Southern states to the other three regions, whereas the Northeast receives those shocks. The West receives shocks from the South and transmits shocks to the Midwest and the Northeast. Finally, the Midwest transmits shocks to the Northeast and receives shocks from the South and the West. Our results have important implications for policymakers and investors. To the extent that the housing market affects the business cycle, the Federal Reserve can monitor housing market movements in the net transmitter states to gather information about the beginnings of the housing market cycle. Moreover, the determination of which states or regions function as the main transmitter of shocks provides information to investors on acquiring housing assets in these markets rather than the ones that are more susceptible to such shocks as net receivers
Establishing social licence to operate solar farms in Aotearoa New Zealand: An analysis of community perceptions in Canterbury : A dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Planning at Lincoln University
No full textAotearoa New Zealand (ANZ) has experienced a proliferation in the number of proposed and consented solar farms in rural areas across the country, positioning grid-connected solar electricity generation as a core component in the transition from fossil fuels to renewable energy sources. In combination with enabling market and socio-political conditions, community acceptance is a critical component for the successful implementation of solar farm developments (Pascaris et al., 2021). International research and literature show that acceptance of solar farms is influenced by numerous factors and varies between different communities and groups of people; however, attitudes and perceptions towards solar farms in ANZ and how these vary by different factors is unknown. Therefore, this research aims to provide a comprehensive picture of community attitudes and perceptions towards solar farms using Canterbury as a case study area and identify opportunities and challenges for establishing social licence to operate for solar farms in ANZ. A quantitative survey questionnaire was developed and shared with groups across Canterbury with a particular focus on rural communities. Of the 447 participants that completed the survey questionnaire, the majority were positive towards solar farms at national, regional and local levels, with 61 percent of respondents expressing ‘positive’ or ‘very positive’ attitudes towards solar farms in their local community. Attitudes varied by participants’ level of knowledge, local land use and district of residence. Socioeconomic and environmental mitigation measures, mixed land use approaches and site selection were identified as factors that may influence acceptance, and the importance of public involvement in the planning process for solar farms was revealed. Overall, the findings from this research highlight the importance of understanding variations in community perceptions and early community engagement and public involvement for effective strategic planning of solar farms, which have several implications for policy and planning in ANZ
Australian non-perennial rivers: Global lessons and research opportunities
No full textNon-perennial rivers are valuable water resources that support millions of humans globally, as well as unique riparian ecosystems. In Australia, the Earth's driest inhabited continent, over 70% of rivers are non-perennial due to a combination of ancient landscape, dry climates, highly variable rainfall regimes, and human interventions that have altered riverine environments. Here, we review Australian non-perennial river research incorporating geomorphology, hydrology, biogeochemistry, ecology, and Indigenous knowledges. The dominant research themes in Australia were drought, floods, salinity, dryland ecology, and water management. Future research will likely follow these themes but must address emerging threats to river systems due to climate change and other anthropogenic impacts. Four high level opportunities for future research are identified, namely: (1) integrating Indigenous and western scientific knowledge; (2) quantifying climate change impacts on hydrological and biological function; (3) clarifying the meaning and measurement of “restoration” of non-perennial systems; and (4) understanding the role of groundwater. These challenges will require inter- and multi-disciplinary efforts supported by technological advances. The evolving body of knowledge about Australian rivers provides a foundation for comparison with other dryland areas globally where recognition of the importance of non-perennial rivers is expanding
Reconsidering the Price equation: Benchmarking the analytical power of additive partitioning in ecology
No full textThe Price approach allows the partitioning of composite variables into a set of additive components and has become an important tool in evolutionary and ecological research. However, because such components are not mutually independent and might be constrained by the inherent data structure, comparing and interpreting Price partitions among different datasets is not straightforward and has contributed to controversy in ecology. Here we discuss and develop null model approaches that might be used as statistical standards to normalise partition values and reduce collinearity between partitions. We use a simulation approach to estimate Price partitions of artificial data and their randomisations. Using structural equation modelling we then reveal the degree of collinearity between raw and standardised partitions. We first demonstrate that the degree of collinearity between partitions strongly depends on the data structure and then provide a general framework for null model selection. Null models that require limited additional information on the possible distribution of species richness and abundance perform best. These null models consistently reduce, but do not fully eliminate, collinearity between partitions. They assign separate type I and II error levels to each partition that differed among partitions. We argue in favour of null models that strike a balance between information need (simplicity) and complexity of additional information, but we discourage the use of simple permutation approaches that have been successful for analysing other biodiversity measures such as species richness. We highlight that the interpretation of additive partitions of complex ecological data will benefit from analyses of the dependence among partitions
Optimising sampling frequency for change detection of variables in lake monitoring programs
No full textA lake monitoring regime optimised to detect natural and anthropogenic variations in water quality is critical for supporting and understanding the impact of lake restoration actions. It can support efficient investment in monitoring by minimising the time required for change detection of lake water quality attributes. The objective of this study was to develop tools and resources to support the development of optimised lake monitoring programs tailored for individual monitored and unmonitored lakes in New Zealand, targeted to detecting change in key water quality attributes in response to restoration actions. We used monitoring data collected routinely from 148 lakes and modelled variability of chlorophyll-a (chl-a), total nitrogen (TN), total phosphorus (TP), and Secchi disk depth (SDD). Using a gradient boosted regression tree (BRT) procedure, we estimated the number of samples per year required over a 5-year and 20-year period to detect improvement in water quality equivalent to meeting thresholds for minimum acceptable water quality states in national policy. At monitored sites, chl-a monitoring to detect improvements within five years was estimated to increase current costs by over 16 times and over 3 times to detect improvements within 20 years. Monitoring to document the effects of restoration actions is important for justifying investments in restoration. Our assessment indicates the importance of monitoring frequency for the level of investment and duration with what is possible to detect the resulting changes in water quality
Can fungal volatile organic compounds (FVOCs) provide control of Sclerotinia sclerotiorum in potato?
No full textSclerotinia sclerotiorum is one of the most devastating soil-borne pathogens of potato in the world, causing white mould disease. In vitro experiments suggest that two fungal organic compounds (FVOCs) from Trichoderma atroviride “type B” have an antagonistic effect on S. sclerotiorum. The main objective of this study is to evaluate these two FVOCs for bio-control of this pathogen in three environmental conditions: in
a glasshouse, a controlled environment and in the field. S. sclerotiorum inoculum will be grown in wheat bran and mixed into the growing medium before the potato tubers are planted. The FVOCs will be infused into an alginate: silicate system as beads then applied adjacent to the tubers. Disease progression in the ‘pathogen only’ control and for the two FVOC treatments will be recorded throughout the growing season. At harvest, yield will be determined and both leaf and tuber samples taken for analysis: chitinase, B-1,3 glucanase, protease inhibitors, phenolic compounds, peroxidase and catalase activity will be recorded, and a transcriptome analysis will be conducted to determine any up/down regulation of genes related to plant defence systems. Our hypothesis is that one or both FVOCs will, via chemical signalling, allow the potato
plant to upregulate its defence pathways, and thus better withstand the pathogen attack
Impact of a Trichoderma volatile organic compound on moisture stressed plants - a glasshouse study
No full textDrought stress causes significant reductions in crop yields and sustainability. This study investigated the impact of a Trichoderma volatile organic compound (VOC) on pasture plant resilience to moisture stress under glasshouse conditions. The VOC was applied to perennial ryegrass and white clover seeds in a polymer. Emergence was delayed slightly in both species by the VOC treatment, but this had no negative impact on subsequent plant biomass in non-moisture stressed plants. When plants were not watered for ten days, control plants wilted severely while plants grown from VOC treated seeds did not. For perennial ryegrass plants the VOC treatment significantly increased plant biomass (by 6%) and for a combination of perennial ryegrass and white clover the increase was 15%. Post drought leaf chlorophyl content as measured by SPAD was also 14% and 18% higher in VOC treated ryegrass and the combination, respectively, than the control plants. These preliminary results suggest a role for this VOC in mitigating the impacts of moisture stress in temperate pasture plants