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The rapidly growing areal extent of oil palm (Elaeis guineensis Jacq.) plantations and their high fertilizer input raises concerns about their role as substantial N2O sources. In this study, we present the first eddy covariance (EC) measurements of ecosystem‐scale N2O fluxes in an oil palm plantation and combine them with vented soil chamber measurements of point‐scale soil N2O fluxes. Based on EC measurements during the period August 2017 to April 2019, the studied oil palm plantation in the tropical lowlands of Jambi Province (Sumatra, Indonesia) is a high source of N2O, with average emission of 0.32 ± 0.003 g N2O‐N m−2 year−1 (149.85 ± 1.40 g CO2‐equivalent m−2 year−1). Compared to the EC‐based N2O flux, average chamber‐based soil N2O fluxes (0.16 ± 0.047 g N2O‐N m−2 year−1, 74.93 ± 23.41 g CO2‐equivalent m−2 year−1) are significantly (~49%, p < 0.05) lower, suggesting that important N2O pathways are not covered by the chamber measurements. Conventional chamber‐based N2O emission estimates from oil palm up‐scaled to ecosystem level might therefore be substantially underestimated. We show that the dynamic gas exchange of the oil palm canopy with the atmosphere and the oil palms' response to meteorological and soil conditions may play an important but yet widely unexplored role in the N2O budget of oil palm plantations. Diel pattern of N2O fluxes showed strong causal relationships with photosynthesis‐related variables, i.e. latent heat flux, incoming photosynthetically active radiation and gross primary productivity during day time, and ecosystem respiration and soil temperature during night time. At longer time scales (>2 days), soil temperature and water‐filled pore space gained importance on N2O flux variation. These results suggest a plant‐mediated N2O transport, providing important input for modelling approaches and strategies to mitigate the negative impact of N2O emissions from oil palm cultivation through appropriate site selection and management. [ABSTRACT FROM AUTHOR]

We construct an SIR-type model for COVID-19, incorporating as a parameter the susceptible individuals' cautiousness level. We determine the model's basic repro- duction number, study the stability of the equilibria analytically, and perform a sen- sitivity analysis to confirm the significance of the cautiousness level. Fixing specific values for all other parameters, we study numerically the model's dynamics as the cautiousness level varies, revealing backward transcritical, Hopf, and saddle-node bifurcations of equilibria, as well as homoclinic and fold bifurcations of limit cycles with the aid of AUTO. Considering some key events affecting the pandemic in In- donesia, we design a scenario in which the cautiousness level varies over time, and show that the model exhibits a hysteresis, whereby, a slight cautiousness decrease could bring a disease-free state to endemic, and this is reversible only by a drastic cautiousness increase, thereby mathematically justifying the importance of a high cautiousness level for resolving the pandemic. [ABSTRACT FROM AUTHOR]

This paper provides a determinant analysis of financial dollarisation hysteresis in Indonesia during 2007–2016 by employing the autoregressive distributed‐lag estimation method. Placing emphasis on the return aspect, this paper indicates that financial dollarisation in Indonesia has been shaped by inflation, the exchange rate, inflation volatility, the exchange rate's volatility and the spread. Given the macroeconomic conditions, ensuring credible inflation targeting, making the rupiah more attractive and building a prudent standard would all help Indonesia to escape from its financial dollarisation hysteresis. [ABSTRACT FROM AUTHOR]

• Introduction: We studied stem sap flux density in seven common tree species in a perhumid tropical rainforest at pre-montane elevation in Sulawesi with the aims (1) to analyse the among-species variation in flow patterns, (2) to search for an assumed convergence in the response to controlling environmental factors, and (3) to investigate the effect of tree size on xylem flux. • Materials and methods: Sap flux density was measured for 20 months in 39 tree individuals of seven species (from six of the most dominant families in the area). Synchronous sap flux density in the outermost xylem differed more than threefold among the species and was highest in the tall Fagaceae Castanopsis acuminatissima. Across the seven species, a tight exponential correlation was found between tree diameter (or tree height) and tree daily water use. • Results: Daily sap flux density correlated better with atmospheric vapour pressure deficit than with shortwave radiation, in spite of the permanently high atmospheric humidity. Soil moisture did not vary significantly and therefore showed no effect on mean daily sap flux density. The hysteresis in the diurnal plot of xylem flux density against vapour pressure deficit or radiation was larger for radiation supporting the close coupling of flux variation to vapour pressure deficit, which exists even in this perhumid climate. • Conclusion: We conclude that the species of this perhumid forest show convergent patterns in the environmental control of sap flux. Largely different water consumption rates of coexisting trees were mainly caused by differences in tree size and the position of the tree within the canopy. Our extrapolated daily stand transpiration rates are low in comparison to other tropical forests which may be a consequence of the permanently high air humidity. [ABSTRACT FROM AUTHOR]