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Context The Australian Alps are recognised by UNESCO as a globally significant mountain range. Soils underpin all of these ecosystem services. However, sparse data exists on alpine soils. Aims and methods We explored nitrogen dynamics of soils from four high mountain sites, using a combination of new and established field and laboratory techniques. Key results Organic and inorganic N were of the same order of magnitude, with around twice as much inorganic N as organic N. Forty three small (k =0.017), while the stabilisation factor was high (0.28) in comparison with other ecosystems globally. Conclusions These results begin to illuminate the complexity of the belowground processes that have formed the high C soils of the Australian Alps. The combination of moderate turnover times and high stabilization of organic matter support Costin’s theory that these mountain soils formed in place as a result of biological activity, rather than reflecting their geological substrata. The pools of organic N adsorbed to mineral soil surfaces and bound up within microbes lend support to a theory of tight N cycling, with little organic or inorganic N free in the soil solution. Implications This new knowledge of soil N dynamics can support land managers to design successful restoration works to preserve alpine soil ecosystem services impacted by climate change, feral animal disturbance, weed invasion and the increase in summer tourism infrastructure.

Australian alpine peatlands are critically important ecosystems that deliver a range of valuable services. However, our understanding of these services in Australia, particularly peatland carbon cycling, is lacking. Here, we quantified peat soil carbon (C) and nitrogen (N) concentrations, C:N ratios, and C density in eight Sphagnum-dominated peatlands on the Bogong High Plains, southeastern Australia. Soil C and N concentrations averaged 16.5 ± 13.2% and 0.6 ± 0.4%, respectively. C:N ratios averaged 30.9 ± 20.4, and C density averaged 46.6 ± 20.7 mg C cm− 3. Our findings suggest that (1) peat biogeochemistry is highly variable between sites, even at small spatial scales; and (2) while not a direct focus of the study, peat depths in this area were relatively shallow, ranging from 30 to 60 cm, most likely due to previous disturbance causing peat removal and carbon loss. Additionally, we present preliminary data investigating CO2and CH4fluxes at these sites. We recommend that future research includes (1) age dating peat cores to better understand the role of disturbance in rates of peat accumulation and loss; and (2) long-term carbon flux studies at multiple peatland sites.

Drainage and conversion of natural peatlands, which increases fire frequency, haze air pollution and carbon emissions, also affects the physical and chemical properties of peat soils. Although there has been continued interest in research on tropical peat soil properties, no attempt has yet been made to synthesise these results. We conducted a systematic literature review and meta-analysis of sixty-six papers published in English language academic literature to explore the current state of knowledge of peat soil properties of Southeast Asia and to compare physical and chemical peat properties (e.g. bulk density, carbon content, pH) under different land uses and depths. Most of these studies were undertaken in Indonesia (56.1%) and Malaysia (28.8%), where substantial tracts of peat soils occur. We extracted data from these papers to calculate the mean of each peat property and compare results between land uses and depths. Linear mixed-effects models were used to test the significance of land use and depth on each peat property. We found that bulk density (44 papers), carbon (C) content (43 papers), pH (42 papers) and nitrogen (N) content (39 papers) were the most widely reported, while other properties remain less studied. Bulk density, pH, phosphorus (P) and calcium (Ca) showed significant differences between land uses and depths. Fibre fraction, potassium (K), iron (Fe) and zinc (Zn) levels showed a significant difference between land uses only, while N differed significantly only between soil depths. Other physical properties such as hydraulic conductivity, porosity, woody fraction, amorphic fraction and chemical properties such as electrical conductivity (EC), C, ammonium (NH4+), nitrate (NO3−), available nitrogen (available N), magnesium (Mg), aluminium (Al), copper (Cu), manganese (Mn), sulphur (S) and silicon (Si) showed no significant differences between land uses or depths. This review identifies key research gaps, including underrepresented geographic areas and peat properties and highlights the need for standardised methodologies for measuring peat soil properties.

Wicked problems such as climate change and the COVID-19 pandemic require authentically transdisciplinary approaches to achieving effective collaboration. There exist several research approaches for identifying the components and interactions of complex problems; however, collaborative autoethnography provides an empirical way to collect and analyze self-reflection that leads to transformative change. Here, we present a case study of collaborative autoethnography, applied as a tool to transform research practice among a group of natural and social scientists, by constructively revealing and resolving deep, often unseen, disciplinary divides. We ask, “How can natural and social scientists genuinely accept, respect, and share one another’s approaches to work on the wicked problems that need to be solved?” This study demonstrates how disciplinary divisions can be successfully bridged by open-minded and committed collaborators who are prepared to recognize the academic bias they bring to their research and use this as a platform of strength.

Peatlands contain a significant fraction of global soil carbon, but how these reservoirs will respond to the changing climate is still relatively unknown. A global picture of the variations in peat organic matter chemistry will aid our ability to gauge peatland soil response to climate. The goal of this research is to test the hypotheses that (a) peat carbohydrate content, an indicator of soil organic matter reactivity, will increase with latitude and decrease with mean annual temperatures, (b) while peat aromatic content, an indicator of recalcitrance, will vary inversely, and (c) elevation will have a similar effect to latitude. We used Fourier Transform Infrared Spectroscopy to examine variations in the organic matter functional groups of 1034 peat samples collected from 10 to 20, 30–40, and 60–70 cm depths at 165 individual sites across a latitudinal gradient of 79°N–65°S and from elevations of 0–4,773 m. Carbohydrate contents of high latitude peat were significantly greater than peat originating near the equator, while aromatic content showed the opposite trend. For peat from similar latitudes but different elevations, the carbohydrate content was greater and aromatic content was lower at higher elevations. Higher carbohydrate content at higher latitudes indicates a greater potential for mineralization, whereas the chemical composition of low latitude peat is consistent with their apparent relative stability in the face of warmer temperatures. The combination of low carbohydrates and high aromatics at warmer locations near the equator suggests the mineralization of high latitude peat until reaching recalcitrance under a new temperature regime. Peatlands are a large global soil carbon reservoir, containing a quantity of carbon that is equivalent to about half or more of the carbon dioxide in the atmosphere. What will be their fate on a warming planet? Across a latitudinal gradient from 79°N to 65°S, we measured the fraction of the peat made up of carbohydrates, which are easily decomposed, and of aromatics, which are less easily decomposed. We found that peat from high latitudes and high elevations had greater carbohydrate content, while aromatic content showed the opposite trend. Larger carbohydrate content in organic matter indicates greater decomposability, while greater aromatic content indicates lower decomposability. We suggest that this latitude/elevation difference that we observed predicts how high‐latitude and high‐elevation peats may change under warmer conditions. Our work indicates that while a large portion of the carbohydrate fraction in these peats could be lost upon warming, releasing greenhouse gases, a residual fraction will survive and become more aromatic‐rich, making the remainder more resistant to rapid decomposition. Peatland soil organic matter stability can be evaluated through the relative abundances of carbohydrate and aromatic content in peatPeat at higher latitudes and elevations has larger carbohydrate and smaller aromatic content relative lower latitudes and elevationsOur results foreshadow a transition of organic matter from higher latitude peatlands to a more recalcitrant form in response to warming Peatland soil organic matter stability can be evaluated through the relative abundances of carbohydrate and aromatic content in peat Peat at higher latitudes and elevations has larger carbohydrate and smaller aromatic content relative lower latitudes and elevations Our results foreshadow a transition of organic matter from higher latitude peatlands to a more recalcitrant form in response to warming

In the south of the Tibet Autonomous Region of China there is a network of valleys where intensive agriculture is practiced. Although considered highly productive by Tibetans, farm incomes in the region are low, leading to a range of government initiatives to boost grain and fodder production. However, there is limited information available on current farming practices, yields, and likely yield constraints. The present paper uses available data and farmer interviews to describe the agro-climate and current systems of crop and livestock production, and considers possible strategies to boost production. Although winters in Tibet are cold and dry, summer and autumn provide ideal conditions for crop growth. Cropping systems are characterised by heavy tillage, frequent irrigation, high seeding rates and fertiliser applications, some use of herbicides, and little stubble retention or mechanisation. Spring barley and winter wheat are the predominant crops, followed by rapeseed, winter barley, and minor fodder and vegetable crops. Average yields for the main grain crops are around 4.0t/ha for spring barley and 4.5t/ha for winter wheat, significantly lower than should be possible in the environment. Farmers typically keep five or six cattle tethered near the household. Cattle are fed diets based on crop residues but are generally malnourished and rarely produce beyond the needs of the family. It is suggested that research and extension in the areas of crop nutrition, weed control, irrigation, seeding technology, and crop varieties should enable significant increases in grain yield. Increases in cattle production will require increases in the supply of good quality fodder. Cereal/fodder intercrops or double crops sown using no-till seed drills might enable the production of useful amounts of fodder in many areas without jeopardising food grain supply, and allow more crop residues to be retained in fields for improved soil health.

•Soil from long-term liming field trials incubated with 13C-labelled crop residue.•Crop residue-induced priming was higher in limed soils.•Archaeal and laccase-like (LMCO) gene abundances correlated most strongly with priming.•pH and N positively correlated with decomposition of soil C & crop residue.•Archaeal and glycoside hydrolase (GH48) gene abundance, pH, N & initial SOC correlate with total CO2.