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Late Pleistocene and Early Holocene aeolian deposits in Tasmania are extensive in the present subhumid climate zone but also occur in areas receiving >1000 mm of rain annually. Thermoluminescence, optically stimulated luminescence, and radiocarbon ages indicate that most of the deposits formed during periods of cold climate. Some dunes are remnants of longitudinal desert dunes sourced from now-inundated continental shelves which were previously semi-arid. Others formed near source, often in the form of lunettes east of seasonally-dry lagoons in the previously semi-arid Midlands and southeast of Tasmania, or as accumulations close to floodplains of major rivers, or as sandsheets in exposed areas. Burning of vegetation by the Aboriginal population after 40 ka is likely to have influenced sediment supply. A key site for determining climate variability in southern Tasmania is Maynes Junction which records three periods of aeolian deposition (at ca. 90, 32 and 20 ka), interspersed with periods of hillslope instability. Whether wind speeds were higher than at present during the last glacial period is uncertain, but shells in the Mary Ann Bay sandsheet near Hobart and particle size analysis of the Ainslie dunes in northeast Tasmania suggest stronger winds during the last glacial period than at present.

Evelyn Fox Keller’s work has long focused on the discontinuities that seem to punctuate discourses on living systems. The discourse of gene action, for example, focuses on the uncanny shift of agen...

Compaction-induced soil degradation is of growing importance as field machinery continues to increase in power and mass. Approaches to managing the impacts of soil compaction include minimisation (reduce load), remediation (tillage) and confinement (control traffic). Integrated ‘swarms’ of low-mass autonomous machinery have recently been suggested as a means of reducing compaction and an alternative to controlled traffic. In this study, combine and potato harvester machinery relationships were used to predict the specifications of potential low-mass harvesters for use in soil compaction modelling. Results suggested that combine harvester gross vehicle mass (GVM) must be less than 6 Mg to keep the modelled soil bulk density below 1.4 Mg m-3. With this constraint, 6-9 small harvesters (~50 kW) would be required to replace one Class 9 (>300 kW) harvester. A fleet of this size would require access to unloading facilities every 2.5-3 min for the modelled yield conditions. For root and tuber harvesting, which results in a high degree of soil disturbance, no low-mass harvester option was found that would avoid compacting the soil to unacceptable limits. Avoiding soil compaction while maintaining acceptable productivity will pose considerable design and logistics challenges for low-mass grain, root and tuber vegetable harvest machinery. The integration of controlled traffic farming (CTF) and medium-capacity autonomous machines (~10-20 Mg GVM for combine harvesters) may be a better solution for both soil compaction and operational logistics than low-mass swarm technology.

The activities of innovation system actors, particularly the importance of networks, entrepreneurs, and the role of intermediaries have not yet been integrated into a framework that explains innovation system performance at the project level. This study contributes by exploring the role of the innovation system’s actors with respect to its performance. Innovation system performance is studied using multiple cases of projects using statistical inference, network analysis, and fuzzy-set qualitative comparative analysis. The number of actors effectively involved in projects is positively associated with innovation system performance. The network of relationships in the case study innovation system was relatively open, such that the contribution of some actors only became available to the system through the conduit of other actors. Both researchers and intermediaries are highly involved and effective, and the intermediaries’ effectiveness contributes to innovation system performance. However, the perceived involvement or effectiveness of these and other actors did not, alone, ensure that the conditions required for innovation system performance were met. The research method and results apply to any innovation project, particularly those in highly regulated, technological fields. The present study’s findings demonstrate the application of innovation system theory at the project level. The study has important implications for integrating entrepreneurial marketing into innovation system policy and practice.

A close partnership between people and partially autonomous machines has enabled decades of space exploration. But to further expand our horizons, our systems must become more capable. Increasing the nature and degree of autonomy - allowing our systems to make and act on their own decisions as directed by mission teams - enables new science capabilities and enhances science return. The 2011 Planetary Science Decadal Survey (PSDS) and on-going pre-Decadal mission studies have identified increased autonomy as a core technology required for future missions. However, even as scientific discovery has necessitated the development of autonomous systems and past flight demonstrations have been successful, institutional barriers have limited its maturation and infusion on existing planetary missions. Consequently, the authors and endorsers of this paper recommend that new programmatic pathways be developed to infuse autonomy, infrastructure for support autonomous systems be invested in, new practices be adopted, and the cost-saving value of autonomy for operations be studied., 10 pages (compared to 8 submitted to PSADS), 2 figures, submitted to National Academy of Sciences Planetary Science and Astrobiology Decadal Survey 2023-2032

Soil health monitoring is crucial to maintain a sustainable agricultural yield and food security. Therefore, the efficiency and accuracy of monitoring methods are of paramount importance. Colourimetric detection relies on a color change given by interaction or reaction between the analyte and a chemical reagent. The colourimetric method must be robust, low-cost, and straightforward and is ideally the best option for the in situ test. Commercial colourimetric test kits often rely on visual inspection with the naked eye to estimate the target level, but the interferences, such as background light intensity and soil color, limit their accuracy and therefore their applicability. As such, these commercial test kits can only provide an estimation of a concentration range instead of quantified results for each analyte. With the use a smartphone, some of these issues can be overcome through normalization and digitization of colourimetric test results. The smartphone is a good starting point to link new technologies, such as artificial intelligence (AI), unmanned devices, and human-machine interface (HMI), to traditional analysis in both agricultural and environmental protection. Furthermore, if combined with the implementation of the chemistry in a microfluidic device, it could provide a cost-effective “lab-on-chip” system for in-field colourimetric application. In this chapter, we focus on the selection of chemical reagents for colourimetric detection, and discuss the possible interferences in both the colourimetric reaction and the digital data processing using smartphones, and then link to the recent progress of microfluidic devices used for colourimetric soil nutrients testing.

Salinity stress tolerance is a complex polygenic trait composed of numerous sub-traits that operate at very different timescales. This work elucidates the time-dependence and physiological mechanisms conferring differential salinity stress tolerance between Atriplex lntiformis (halophyte) and Medicago arborea (glycophyte) exposed to prolonged NaCl treatments grown in various soil types. Plant (leaf sap Na+, K+ and Cl− concentrations and osmolality, chlorophyll content, stomatal conductance) and soil characteristic (pH, soil and leachate electrical conductivity) were measured at monthly intervals for up to five months of salinity treatments and then correlated with each other. The overall poor performance of salt-grown M. arborea (compared with A. lentiformis) was associated with several factors. This included: (i) its strong reliance on organic osmolytes (hence, associated carbon costs) for osmotic adjustment; (ii) poor K+ retention that compromised stomatal opening; (iii) its inability to prevent Na+ loading into the xylem; and (iv) its poor shoot tissue tolerance, most likely due to inability to provide efficient Na+ sequestration in vacuoles. Also, the salinity of sandy loam soil was only ~50% of the salinity of irrigation water suggesting the possibility of long-term usage of saline irrigation in soils with low clay content.

The concept of irrigating crops with saline irrigation water is not new, but impacts of this practice on soil properties remain debatable, particularly the use of highly saline water. In this work, key soil chemical properties were assessed to a depth of 300 cm following 2.5 years of application of highly saline irrigation to a sodic texture-contrast soil (Brown Sodosol) in south-eastern Tasmania, Australia. Control plots (rainfall only) were compared to irrigation treatments of low (0.8 dS/m) and high salinity (16 dS/m) waters at application rates of both 200 and 800 mm/year. Whilst significant increases in both electrical conductivity and chloride concentration occurred throughout the soil profile in the high salinity treatment, these values were well below those of the irrigation water, indicating effective deep leaching. In the upper soil profile, 0–50 cm, of the high salinity treatments both the exchangeable Na+ and its ratio to total base cations (ESP) were significantly increased whilst the lower soil profile between 50 and 200 cm, was improved via both reduced alkalinity and sodicity. Leaching of the exchangeable base cations Ca2+, Mg2+ and K+ was significant in the upper soil profile (0–50 cm). As expected, the low salinity treatment (0.8 dS/m) had minimal impacts on soil chemical properties. The upper topsoil (0–10 cm) total organic carbon was significantly reduced in the high salinity plots and was negatively correlated with Cl− concentration. The data confirms the general concerns about application of saline irrigation, namely increased whole profile salinisation and upper soil profile (0–50 cm) sodicity, but they also show unexpected and desirable reductions in the lower soil profile (> 50 cm) alkalinity and sodicity. It appears the Na+ ions present in the saline waters led to differential leaching of base cations from the rooting zone, especially Ca2+ which then ameliorate the alkalinity and sodicity deeper in the soil profile (> 50 cm). Thus, surface application of gypsum may help sustain the application of highly saline waters; alternatively, subsurface irrigation above the sodic clayey subsoils could be trailed.

The increased use of biochar as a soil amendment to alleviate the impact of agricultural practices on climate change has been a motivation for many studies to determine the effects of biochar on soil properties, particularly the abundance and activities of soil microbes and related biological processes. This study investigates the impact of different application rates of wood-derived biochar on community structure, nitrogen-cycling and methanotrophic bacteria in three soil types. Biochar was added at 0, 2.5, 5 and 10% w/w to black clay loam (BCL, Vertosol), red loam (RL, Dermosol) and brown sandy loam (BSL, Kurosol) soils. Soil chemical analysis and 16S rRNA gene amplicon sequencing using the IIlumina Mi-Seq platform were conducted on initial samples and after 10-month incubation. The results indicated that the addition of biochar loading levels to the different soils had a significant impact on NH4 and NO3, total C and N, pH, electrical conductivity (EC) and soil moisture content. These changes were reflected in significant differences in the bacterial diversity between biochar treatments in the BSL and RL soils, while the BCL soil was more resilient to change. Complete ammonia-oxidising (Nitrospira) and nitrite-oxidising bacteria (NOB) were more abundant than standard ammonia-oxidising bacteria (AOB) in all soils. Increased biochar loading raised the abundance of nitrifying bacteria in BCL soil while Nitrospira became more abundant in BSL soil. Biochar addition affected the abundance of certain N2 fixer groups in a soil-dependent manner. Strong positive correlations were observed in Rhizobium (r = 0.99) and Azospirillum abundance (r = 0.70) with increased biochar loading rates in BCL. Greater biochar loading also significantly increased the relative abundance of methanotrophs, especially in BCL soil. The impact of biochar on community structure and nitrogen-cycling bacteria depended on soil types and biochar rates which correlated to the differences in soil properties. Overall, the abundance of nitrogen-cycling bacterial groups seemed to be most affected by the changes in soil conditions, including aeration, C/N ratio, nutrients and pH in relation to biochar application in different soils. These changes show that short-term biochar loading influences community structure and leads to increases in populations of methanotrophic and nitrifying bacteria.

A replicated trial was set up to study the physico-chemical changes following 4 years of subsurface drip irrigation (SDI) in a commercial processing tomato field near Shepparton, Victoria, Australia. The study also compared the effect of 0 and 150 L ha-1 of the product GYP-FLO injected through the established 4-year-old SDI lines. Soil samples were collected from five different locations around the dripper emitters to assess the cumulative effects of this irrigation method and also the application of GYP-FLO on some soil physico-chemical properties. Water-stable aggregate (WSA), Emerson dispersion, particle size distribution (PSD), electrical conductivity (EC), soil pH, exchangeable cations (Ca2+, Mg2+, K+ and Na+) were measured and exchangeable sodium percentage (ESP), Ca:Mg ratio and effective cation exchange capacity (ECEC) were then calculated from these primary data. The results showed that, after 4 years of SDI, there were significant increases in EC (P

Innovation systems provide a structured approach to understanding innovation performance and failure. Two innovation system theories, structural and functional, provide the basis for understanding the failures of projects within the single innovation system under investigation. Many indicators of the strength of conditions in the model are important to innovation system performance. Fuzzy set qualitative comparative analysis is suitable for the validation of formative measurement models. The survey instrument meets validity criteria to the extent of this research and is a useful diagnostic tool for innovation system performance.

Innovation systems provide an approach to understanding, and managing, the innovation process. The application of structural theory from the sectoral innovations systems literature and the functional theory from technological systems literature to a series of projects provides an opportunity to explore how weaknesses in the innovation system relate to innovation failure. Findings from fuzzy set qualitative comparative analysis of multiple cases indicate that the weaknesses of the innovation system are recurrent across cases, and therefore, amenable to policy or management intervention to improve innovation outcomes. The weaknesses in structural theory conditions are more consistent than the weaknesses in technological theory conditions.

Background: Young saplings of Hopea odorata, a native dipterocarp in Vietnam, require shading to prevent photoinhibition but they must avoid competition that stagnates their growth.Aims: To develop a silvicultural regime by examining how the biomass production of H. odorata changes along a light gradient in gaps within Acacia hybrid plantations.Methods: Hopea odorata saplings were planted in 22-m-diameter circular gaps within a 3-year-old Acacia hybrid plantation and in 5-m and 7.5-m-wide strip gaps within a 2.5-year-old Acacia hybrid plantation.Results: In the circular gap, biomass growth increased nearly tenfold from the gap perimeter (GP) to about 9 m from the perimeter, and then decreased. This was associated with a fivefold increase in the absorption of photosynthetically active radiation (APAR) and a nearly twofold increase in light-use efficiency (LUE). The increasing APAR was primarily related to increasing H. odorata crown sizes and a reduction in shading from the Acacia hybrid. In the strip gaps...