Entropy production (σ) is a measure of ecosystem and landscape stability in a changing environment. We calculated the σ in the radiation balance for a well-drained spruce forest, a paludified spruce forest, and a bog in the southern taiga of the European part of Russia using long-term meteorological data. Though radiative σ depends both on surface temperature and absorbed radiation, the radiation effect in boreal ecosystems is much more important than the temperature effect. The dynamic of the incoming solar radiation was the main driver of the diurnal, seasonal, and intra-annual courses of σ for all ecosystems; the difference in ecosystem albedo was the second most important factor, responsible for seven-eighths of the difference in σ between the bog and forest in a warm period. Despite the higher productivity and the complex structure of the well-drained forest, the dynamics and sums of σ in two forests were very similar. Summer droughts had no influence on the albedo and σ efficiency of forests, demonstrating high self-regulation of the taiga forest ecosystems. On the contrary, a decreasing water supply significantly elevated the albedo and lowered the σ in bog. Bogs, being non-steady ecosystems, demonstrate unique thermodynamic behavior, which is fluctuant and strongly dependent on the moisture supply. Paludification of territories may result in increasing instability of the energy balance and entropy production in the landscape of the southern taiga.

For the first time, the information is summarized on the history of establishment, the state of observations and the main scientific results on sites included in RuFlux, the Russian eddy covariance network for the monitoring of greenhouse gases (GHG). Eddy covariance technique provides estimates of GHG fluxes at the level of ecosystems. The long-term series of GHG fluxes (more than 190 site-years of observations) have been obtained. Up to the end of 2022, 86% of the sites of the RuFlux network are located in forests and wetlands, 77% of all sites are in the middle and southern taiga. Almost all undisturbed ecosystems in Russia are the sinks of CO2 from the atmosphere with a range of average annual estimates of net absorption from 80 to 240 g C m–2 yr–1. The GHG balance is determined by a complex of abiotic and biotic factors. The average long-term net CO2 absorption is higher in permafrost Siberian larch forests than in European spruce forests. When moving from west to east, the intensity of CO2 sink in the middle of summer increases, and the emission of CO2 in the middle of winter decreases sharply. Natural and anthropogenic disturbances lead to the transformation of the carbon balance by increasing the release of CO2 into the atmosphere. RuFlux network covers a wide range of types of ecosystems, but it is needed to organize more GHG sites in tundra, northern taiga, forest-steppe, steppe, and semi-deserts; in the ecosystems disturbed by humans (including fields) and in the ecosystems with successions caused by natural disturbances.

How does the activity of the ecosystem of monsoon tropical forest decrease during the dry season of more than 4 months? To answer this question, the dynamics of evapotranspiration is analyzed in the national park of Cát Tiên (Southern Vietnam) using continuous eddy covariance and meteorological dataset for 2012–2013. A comparison of evapotranspiration between Cát Tiên and 21 sites in different tropical forests over the world is performed. It is shown that the abundance of resources of energy and moisture in the annual cycle, as well as the storage of water from the rainy season allows monsoon ecosystem to implement the proactive vegetation during the dry season and make specificity of ecosystem energy and water fluxes in Cát Tiên forest similar to the rainforests.

We present E-CAHORS—a compact mid-infrared open-path diode-laser spectrometer designed for the simultaneous measurement of carbon dioxide, methane, and water vapor concentrations in the near-surface atmospheric layer. These measurements, combined with simultaneous data from a three-dimensional anemometer, can be used to determine fluxes using the eddy-covariance method. The instrument utilizes two interband cascade lasers operating at 2.78 µm and 3.24 µm within a novel four-pass M-shaped optical cell, which provides high signal power and long-term field operation without requiring active air sampling. Two detection techniques—tunable diode laser absorption spectroscopy (TDLAS) and a simplified wavelength modulation spectroscopy (sWMS)—were implemented and evaluated. Laboratory calibration demonstrated linear responses for all gases (R² ≈ 0.999) and detection precisions at 10 Hz of 311 ppb for CO₂, 8.87 ppb for CH₄, and 788 ppb for H₂O. Field tests conducted at a grassland site near Moscow showed strong correlations (R = 0.91 for CO₂ and H₂O, R = 0.74 for CH₄) with commercial LI-COR LI-7200 and LI-7700 analyzers. The TDLAS mode demonstrated lower noise and greater stability under outdoor conditions, while sWMS provided baseline-free spectra but was more sensitive to power fluctuations. E-CAHORS combines high precision, multi-species sensing capability with low power consumption (10 W) and a compact design (4.2 kg).

We present E-CAHORS $-$ a compact mid-infrared open-path diode-laser spectrometer designed for the simultaneous measurement of carbon dioxide, methane, and water vapor concentrations in the near-surface atmospheric layer. These measurements, combined with simultaneous data from a three-dimensional anemometer, can be used to determine fluxes using the eddy-covariance method. The instrument utilizes two interband cascade lasers operating at 2.78 $μ$m and 3.24 $μ$m within a novel four-pass M-shaped optical cell, which provides high signal power and long-term field operation without requiring active air sampling. Two detection techniques $-$ tunable diode laser absorption spectroscopy (TDLAS) and a simplified wavelength modulation spectroscopy (sWMS) $-$ were implemented and evaluated. Laboratory calibration demonstrated linear responses for all gases (R$^2$ $\approx$ 0.999) and detection precisions at 10 Hz of 311 ppb for CO$_2$, 8.87 ppb for CH$_4$, and 788 ppb for H$_2$O. Field tests conducted at a grassland site near Moscow showed strong correlations (R = 0.91 for CO$_2$ and H$_2$O, R = 0.67 for CH$_4$) with commercial LI-COR LI-7200 and LI-7700 analyzers. The TDLAS mode demonstrated lower noise and greater stability under outdoor conditions, while sWMS provided baseline-free spectra but was more sensitive to power fluctuations. E-CAHORS combines high precision, multi-species sensing capability with low power consumption (10 W) and a compact design (4.2 kg).