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Learning by doing is more memorable: Soil judging as an educative tool in New Zealand
No full textSoil scientists are increasingly working in a multidisciplinary world where they interact with professionals from different disciplines and diverse end user groups. The ability to communicate, and to be an effective team player are just as important skills as the ability to apply practical field skills and describe soil profiles. The kinaesthetic approach embodied in soil judging allows the student to also connect with pedological theory; and it is a pedagogically aligned style of learning.
At Lincoln University we first adopted innovative, experiential learning in the form of soil judging in 2016 to address these issues, and have worked collaboratively with Manaaki Whenua Landcare Research to develop this programme. Soil judging in New Zealand is in its infancy compared to other countries, but the undergraduate student soil science society and academic staff have been enthusiastic in practicing soil description skills and land use interpretation, participating in soil judging contests in New Zealand and Australia. Students report that they have become more confident in soil description and that it has stimulated their interest in learning about soil science. We designed a micro credential to recognize the academic work of the students. Several soil judging graduates have secured employment as pedologists at Crown Research Institutes or as soil resource specialists in local / regional government organisations. Soil judging may also be an effective recruitment pipeline into the discipline: offering those students with a practical and kinaesthetic aptitude who perform well at soil judging an insight into the academic side of the soil science discipline. We posit that soil judging competitions are an effective framework for students to acquire a valuable range of practical, field-based skills for a professional career in soil science or allied enterprises
Assessing the influence of climate change and clonal diversity on berry composition of Malbec
No full textOver the 21st century, the projected increases in regional temperatures and shifts in rainfall patterns and extreme weather events are expected to have important consequences on viticulture. They vary from short-term impacts on wine volume and quality, to long-term issues such as varietal or vineyard suitability to remain economically sustainability. With a focus on Malbec in France, this study aimed to assess the influence of climate change and clonal diversity on berry composition. The first part investigated the extent to which climate change has altered the berry composition of Malbec, cultivated in the Touraine sub-region of the Loire Valley. A long-term evaluation (1971-2020) was made concerning the modifications in sugar and total acidity content, including the ripening speed and specific heat requirements to reach different sugar levels. The second part evaluated the berry composition traits (sugar, total acidity, pH and berry weight) of 216 Malbec clones, prospected initially in Cahors and Touraine (France), including Mendoza (Argentina). These selected clones were then studied during 7 consecutive seasons (2014-2020) to understand the influence of the intra-varietal diversity of Malbec on berry composition. The results showed important modifications for berry composition and ripening speed, with significant higher sugar and lower total acidity contents over the past 50 years. Findings further revealed a strong intra-varietal diversity for the studied berry composition traits, highlighting the importance of gaining a deeper understanding of the intra-varietal spectrum and their adaptive potential to climate change
A global review of the trends and themes in polar tourism scholarship
No full textIn recent years, we have witnessed a proliferation in the scholarly output related to the study of polar tourism. Having made a first appearance as an area of research in its own right almost five decades ago, scholarship on polar tourism has undergone a significant transformation and is now more likely to be underpinned by empirical, multi- disciplinary, multi- authored and theoretically situated research than in the past. Updating previous reviews, this chapter systematically reviews 626 journal articles published on polar tourism (1974–2022) and identifies key research trends and themes. Following Stewart et al. (2005, 2017), a database of journal articles was updated through a keyword search of two online scholarly databases (Scopus and Google Scholar) and other regionally relevant search engines and compiled into a spreadsheet for analysis. The chapter extends the previous reviews by including articles published in languages other than English (22 languages). By doing so, this review presents, for the first time, a comprehensive overview of scholarly output on polar tourism, benefiting from the international research efforts that have been undertaken. While the chapter reports a dominance of anglophone articles (almost 75% of all papers), there is an upswing of scholarly work outside of the anglophone literature. This linguistic diversity stands us in good stead to advance our understanding of polar tourism in its many guise
Inclusion of leguminous green manures enhances crop biomass, nutrient uptake, soil phosphorus dynamics and bioavailability
Get PDFIntroduction: In agroecosystems, phosphorus (P) applications over a long time have accumulated in soil as legacy P. This environmental challenge can be an agronomic opportunity as soil legacy P could be recovered in cropping systems using practices such as green manuring. We hypothesised that, at moderate soil available P levels, plant-soil interactions under green manures can mobilise soil legacy P and promote cereal crop P uptake and growth.
Methods: Alongside a fallow treatment, three green manure treatments that included two legume treatments (narrow-leaf lupin [Lupinus angustifolius], pea [Pisum sativum L.]) and one cereal treatment (wheat [Triticum aestivum] and barley [Hordeum vulgare]) were rotated with the main crops of wheat and barley in two phases on a pumice soil (27 mg kg‾¹ Olsen P) in a microcosm experiment. Plant roots and shoots and end-of-experiment soil samples were collected for analysis.
Results: Over two crop rotations, inclusion of narrow-leaf lupin and pea green manures significantly increased main crop biomass (27%–35%) and P uptake (15%–29%) relative to control, while the cereal green manure decreased the following crop's yield (−13%) and P uptake (−19%). Relative to fallow, microbial biomass P and soil organic P pools increased under all green manures yet total inorganic P decreased under leguminous green manures. This depletion (35 mg P kg‾¹) under narrow-leaf lupin was equivalent to ∼47 kg P ha‾¹. Phosphatase enzyme activities relevant to P cycling increased particularly under leguminous green manure treatments.
Conclusions: Leguminous green manures such as narrow-leaf lupin could mobilise soil P to crops in field conditions, suggesting that drawdown of soil legacy P while sustaining crop yield can be tenable
Drivers of grape berry sugar accumulation in field conditions at local scale
Get PDFThe final sugar concentration in grapes is an important parameter for winegrowers as it determines the alcohol content by volume of the final wine, allowing the timing of harvest to be optimised. In this research, a comprehensive dataset spanning seven years and 18 sites located in Saint-Émilion, Pomerol and satellite appellations (Bordeaux, France) was used to assess how growth and developmental factors (berry weight and mid-veraison date, respectively) and environmental factors (vine water status, nitrogen status, and mean air temperature) influence the dynamics of sugar accumulation. The results of this study highlight the strong influence of mean temperature on the timing of maximum sugar accumulation, the duration of sugar accumulation and maximum sugar concentration in grape berries. Berry weight and the rate of sugar accumulation also appeared to be significant drivers of final sugar concentration. Fast ripening and increased berry weight were associated with lower sugar concentrations. Sites were clustered according to parameters driving sugar accumulation dynamics and mapped at the scale of the study area, in order to link these findings to terroir expression. In this study, vine nitrogen status did not emerge as a significant explanatory variable in any of the models developed to analyse sugar accumulation dynamics and berry weight. A small but significant effect of vine water status on the precocity of the plateau and on berry weight was found. These results provide a better understanding of the factors that affect the dynamics of sugar accumulation in grape berries, which can help vine growers adapt to climate change. For example, by promoting practices that delay the onset of ripening to shift to a cooler period of ripening through choice of plant material and management practices. Alternatively, this can be done through an increase in berry weight, which lowers grape sugar and therefore wine alcohol concentration, taking care not to excessively alter the skin-pulp ratio to avoid reducing secondary metabolite
Identification of the best viticultural areas by spatial optimisation. Application in New Zealand South Island in the context of climate change
No full textThe global winegrowing sector is under pressure due to the effects of global climate change. This is particularly true for New Zealand, where the wine industry is limited to a few regions. This study focuses on the South Island of New Zealand. It uses the Multi-objective Optimisation for Agrosystems (MOA) model to (i) investigate how potential exposure to climate risks and phenological stages will evolve under climate change, (ii) assess the suitability of current vineyards for viticulture in the future, and (iii) investigate potential emerging areas favourable for viticulture.
The results show that a significant shift in the phenological stages of veraison and ripeness can be expected in the future due to the warming of the South Island of New Zealand. The projected phenological stages advancement is around one week in the near term for both Shared-Socioeconomic Pathways studied (SSP2-4.5 and SSP5-8.5) and is more than three weeks and one month in long-term for SSP2–4.5 and SSP5-8.5 respectively. A regional to local increase in frost risk (Canterbury, Otago, and Southland) and a slight increase in disease risk (especially on the coast) are also projected in the future, while the South Island of New Zealand is not expected to be affected by heatwaves. The results show that Marlborough, New Zealand's most important winegrowing region, will continue to be one of the best areas for viticulture in the 21st century. On the other hand, new winegrowing opportunities are expected to emerge inland and southwards.
Overall, this study contributes to the understanding of the impact of climate change on the New Zealand wine industry and emphasises the need to adapt to changing climate conditions. It also provides insights into the future suitability of vineyards and identifies potential expansion areas for the New Zealand viticulture sector
Damage costs from invasive species exceed management expenditure in nations experiencing lower economic activity
No full textWhile data on biological invasions and their economic toll are increasingly available, drivers of susceptibility to damage and cost-effectiveness of management in reducing long-term costs remain poorly understood. We used data describing the damage costs of, and management expenditure on, invasive species among 56 nations between 2000 and 2020 reported in the InvaCost database to test the overarching hypothesis that higher-income nations and those with higher trade volume have a higher efficiency to limit the damage incurred by invasive species by spending relatively more on management. We also tested whether nations with (i) more corruption have a reduced capacity to manage invasive species, leading to relatively higher damage costs, (ii) more educated citizens or greater technological and scientific output allow for improved incentives and ability to manage invasive species, thereby reducing relative damage costs, and (iii) economies based on higher primary resource dependencies (e.g., agriculture) are at greater risk of incurring high costs of invasive species, and so all other conditions being equal, have higher relative damage costs compared to management expenditure. By focusing on the ratio between damage costs and management expenditure, we analyse the willingness of countries to invest in management as a function of the extent of the damage suffered. We show that economic activity, measured by the volume of trade, is the main determinant of this ratio — the greater the volume, the smaller the ratio. We also found a higher rate of increase in the damage:management ratio as a country's proportion of total land area devoted to agriculture increased, suggesting that a higher economic dependency on agriculture predisposes a country to greater damage costs from invasive species over time. When considering the proportion of total costs identified as damage-related, results indicated that higher government investment in education produced higher proportional damage, and lower corruption and lower trade volume both reduced proportional damage. Our overall results suggest that wealthier nations with high per-capita imports of goods and services are more susceptible to damage, but also have a greater capacity to reduce it, and are therefore less threatened by biological invasions than countries with fewer resources and lower imports
Connecting people to soil: Learnings from the application of the Food-Landscape Networks framework
No full textThere is a disconnect between people and soil, which is being exacerbated as our populations become increasingly urban-based. This presents a ‘wicked’ challenge for soil and food security that soil science alone is unable to address. A transdisciplinary research methodology was applied to develop a recently proposed framework, Food-Landscape Networks (FLN), that applies a holistic approach to understanding the reciprocal connections between soil, food, and people in contemporary local food production systems. This framework weaves mātauraka Māori and soil science to look beyond the boundaries of soil science to guide the reconnection of people and soil. The framework consists of six interrelated factors, situating soil health at its centre, that are used to assess the reciprocal connections between soil, food, and people.
Our research applies the FLN framework to three food-landscapes in the Waitaha Canterbury region: conventional, organic, and community gardens producing potatoes and/or spinach. Applying the FLN framework reveals clear disconnects between soil, food, and people in these landscapes. It also underscores the urgent need for interdisciplinary collaborations to prevent these disconnects from worsening and to facilitate the reconnection of people and soil through food production.
Key findings from applying the FLN framework include identifying that a disconnect between soil, food, and people occurs in all three food-landscapes assessed, with community gardens exhibiting the strongest connection between soil and people. For the disconnect between people and soil to be addressed, the connections between soil and food, and food and people need to be considered in the context of the reciprocal relationships encompassing factors included in the FLN framework, requiring interdisciplinary collaboration before the consumer reconnection can be achieved
Milk urea concentration and nitrogen use efficiency of dairy cows grazing different levels of forage plantain with ryegrass-white clover
No full textContext: Milk urea (MU) is a by-product of crude protein metabolism in dairy cattle whereby diets with lower nitrogen (N) utilisation are typically associated with greater MU concentrations. Thus, MU is recognised as a useful indicator of dietary N use efficiency (milk N divided by N intake; NUE). Forage plantain has been shown to decrease MU, potentially due to its lower content of ruminal degradable protein compared with ryegrass-white clover (RGWC). However, there are limited data on how including plantain in a farm system affects MU concentration and NUE in dairy cattle throughout an entire lactation period.
Aims: In this study, we investigated the effects of different levels of forage plantain in the farm system on MU and NUE.
Methods: Data were collected over two dairy production years (2021/22 and 2022/23) as part of a farm system study established in late July 2021 at Lincoln University Research Dairy Farm. Nine herds (12 cows each) were randomly allocated into one of three replicated pasture treatments (n=3) sown with an increasing plantain (cv. Ecotain) seed rate: (i) RGWC with nil plantain (PL0); (ii) RGWC+3 kg/ha plantain (PL3); or (iii) RGWC+6 kg/ha plantain (PL6). Individual cow milk volume was measured at each milking (DelPro, DeLaval), with milk composition determined fortnightly (CRV, Hamilton, New Zealand) using samples collected at consecutive afternoon and morning milkings. Fortnightly pre-grazing pasture samples, coinciding with milk samples, were collected to determine botanical and chemical composition. Dry matter (DM) intake was back-calculated from the energy requirements for cows in each herd. Statistical analysis was conducted using General Analysis of Variance with pasture treatment, season of the year and production year included as factors, and farmlet as the experimental unit.
Key results: There was an interaction between treatment × season for plantain % in diet DM, N intake, diet N:ME ratio and NUE, and between treatment × season × year for N intake and diet N:ME ratio. Regardless of season and year effects, average dietary content (% DM) of plantain leaves was 0.1% in PL0, 14.7% in PL3 and 17.7% in PL6. Average estimated daily intake of pasture (14.4 kg DM/cow), supplement (baleage; 1.2 kg DM/cow) and N (476 g/cow) were similar across treatments. Average daily milksolids production per cow was similar between PL0 (1.65 kg) and PL3, and PL0 and PL6, but higher (P=0.015) in PL6 than PL3 (1.66 vs 1.61 kg). Average MU concentration was higher in PL0 than PL3 and PL6 (P<0.001), which did not significantly differ from each other (Table 1). The two-way interaction effect showed that NUE was lower in PL3 than PL0 and PL6 in late-winter, similar between treatments in spring, higher in PL6 than PL3 in summer and higher in PL6 than PL0 in autumn.
Conclusions: While the effect of plantain incorporation into RGWC- based dairy systems at either 14.7 or 17.7% of diet DM resulted in a seasonally dependent response in cows' NUE, it consistently reduced their MU concentration.
Implications: The presence of forage plantain may need to be considered if MU concentrations are used as indicators to help manage herd nutritional status and environmental risk
Validation of a remote sampling sensor for measuring urine volume and nitrogen concentration in grazing dairy cattle
No full textThe purpose of this research was to validate a urine sensor (Lincoln University PEETER V2.0, Canterbury, New Zealand) that records the time and volume of urination events for dairy cows in addition to collecting a proportional urine sample from all urination events. Sixteen multiparous Holstein × Jersey mid-lactating cows (101 ± 5 days in milk, 498 ± 24.2 kg body weight, 26.2 ± 3.07 kg/d milk yield; mean ± standard deviation) were allocated herbage diets ranging in protein and sodium content to generate a range of urine volumes and urine nitrogen (UN) concentrations. Total collection of individual urination events occurred during a 72-h measurement period where PEETER V2.0 sensors were attached to cows. A mixed model ANOVA using lme4 package (version 1.1-35.5) in R (version 4.3.3) were used to compare the means. The average urine event size was 2.65 ± 1.1 L for total collection by observers and 2.68 ± 1.1 L as recorded by the sensor (mean ± standard deviation; p = 0.730). The urine nitrogen concentration was 5.76 ± 1.2 g N/L for samples collected by observers and 5.85 ± 1.3 g N/L for the samples collected by the sensor (p = 0.583). The calculated UN excretion was 156 ± 45.1 g/day for direct measurements and 162 ± 40.0 g/day for the sensor (p = 0.539. Contrasts with simultaneously measured data were undertaken using Lin’s Concordance Correlation Coefficient (CCC) and a Pearson correlation coefficient (r). Correlations between the actual values and sensor values were strong, with little to moderate variability in the urine volume (CCC = 0.936, r = 0.937; n = 222), UN concentration (CCC = 0.840, r = 0.837, n = 48) and total UN excretion (CCC = 0.827, r = 0.836, n = 24). Considering the findings, the PEETER V2.0 urine sensor has the potential to reliably measure urine volumes and UN concentrations for estimations of the UN excretion of dairy cattle under grazing systems