Capacitive-Touch-Based Soil Monitoring Device with Exchangeable Sensor Probe

The aim of this research was to determine how changes in soil moisture and temperature influence ecosystem C fluxes in the context of changing grazing regimes in subalpine grasslands in the Pyrenees. We (i) measured CO2 fluxes in the field in cattle- and sheep-grazed areas, and (ii) compared responses of CO2 and CH4 fluxes from soil turf samples from cattle- and sheep-grazed areas to changes in soil temperature and moisture. The cattle-grazed area showed greater ecosystem respiration and gross ecosystem photosynthesis than the sheep-grazed areas. With respect to the temperature and moisture treatments, the two areas responded in a similar way: Soil moisture was the strongest driver of soil respiration rates; although temperature also increased CO2 effluxes from the soils, the effects were transient. The greatest effluxes of CO2 were found in soils incubated at elevated temperature and 80% soil moisture content. Methane fluxes were only influenced by the moisture treatment, with the greatest methane oxidation rates found at 40% soil moisture content. We conclude that regional changes in moisture availability resulting from climate change are likely to be the most important driver of soil respiration and methane fluxes in these grazed subalpine ecosystems.

Influence of changes in rainfall and soil moisture on trends in flooding

Ongoing research emphasizes the vital role of advanced scientific knowledge in addressing complex wastewater management challenges. Efficient catalysts for degrading pollutants like nitrophenols and organic dyes are crucial for sustainable water quality, resource preservation, and cost-effective solutions. Herein, highly stable and magnetically recoverable Bi3+-doped Ni–Cu–Cr quinary spinel ferrite nanoparticles, synthesized using sol–gel technology, were proposed as heterogeneous nanocatalysts for removing pollutants like nitrophenols and dyes from wastewater. The optical band gap values obtained from DRS lies in the visible range (1.35–1.60 eV) making them suitable and reliable photocatalysts. The augmentation in BET surface area observed with the escalating Bi3+ doping levels signifies an increased availability of active sites conducive to facilitating reactions. Moreover, all the Ni–Cu–Cr ferrites show tremendous results in the reduction of 4-NP and photocatalytic degradation of RhB, but the BF-4 nanocatalyst exhibits the best results among all the other catalysts (reduction of 4-NP and degradation of RhB was 99% completed in 21 and 40 min, respectively). Considering the above fascinating results, we have also extended our scope of work for the reduction of 2-NP, 3-NP, and 2,4,6-TNP and degradation of MB, MO, and a mixture of all organic dyes, i.e., RhB + MB + MO. It was observed that BF-4 swiftly reduces as well as degrades all types of pollutants in the shortest period of time confirming the versatility of our BF-4 nanocatalyst. Moreover, we delved into the degradation mechanism of dyes by investigating the impact of active species, including O2–• and OH• through scavenging experiments, and as a result, OH• was identified as the main contributor to the degradation of dyes. As indicated by the VSM studies, the BF-4 nanocatalyst was easily recoverable using an external magnet and can be used again for recycling reactions. In the context of wastewater management and water resource preservation, our Bi3+-doped Ni–Cu–Cr quinary ferrites stand out as ideal candidates. Their exceptional stability and robust catalytic activity make them a top choice for effectively removing and degrading a wide range of pollutants, contributing to the improvement of water quality and the sustainable management of water resources.

Abstract. Climate change affects water availability for soil, and groundwater extraction influences water redistribution by altering water demand, both of which significantly affect soil moisture. Quantifying their relative contribution to the changes in soil moisture will further our understanding of the mechanisms underlying the global water cycle. In this study, two groups of simulations were conducted with and without groundwater (GW) extraction (estimated based on local water supply and demand) from 1979 to 2010 using the Chinese Academy of Sciences land surface model, CAS-LSM, with four global meteorological forcing datasets (GSWP3, PRINCETON, CRU-NCEP, and WFDEI). To investigate the contribution of climate change and GW extraction, a trajectory-based method was used. Comparing the simulated results with the in situ dataset of the International Soil Moisture Network (ISMN) and the satellite-based soil moisture product of the European Space Agency's Climate Change Initiative (ESA-CCI) indicated that the CAS-LSM reasonably reproduced the distribution of soil moisture and matched the temporal changes well. Globally, our results suggested a significant decreasing trend in surface soil moisture (0–10 cm, 0.98×10-4 mm3 mm−3 yr−1) over the 32-year period tested. The drying trends were mainly observed in arid regions such as the tropical desert regions in North Africa and the Arabian Peninsula, while the wetting trends were primarily in tropical forested areas in South America and northeastern Asia. Climate change contributed 101.2 % and 90.7 % to global drying and wetting trends of surface soil moisture, respectively, while GW extraction accounted for −1.2 % and 9.3 %, respectively. In deep soil, GW extraction contributed 1.37 % and −3.21 % to the drying and wetting trends, respectively. The weak influence of GW extraction may be because this activity occurs in limited areas. GW extraction contributed more than 35 % to the change in surface soil moisture in wetting areas where GW overexploitation occurs. GW is mainly extracted for irrigation to alleviate soil water stress in semiarid regions that receive limited precipitation, thereby slowing the drying trend and accelerating the wetting trend of surface soil. However, GW exploitation weakens the hydraulic connection between the soil and aquifer, leading to deeper soils drying up. Overall, climate change dominated the soil moisture trends, but the effect of GW extraction cannot be ignored.

Reduced throughfall decreases autotrophic respiration, but not heterotrophic respiration in a dry temperate broadleaved evergreen forest

We studied the influence of the statistical properties of soil moisture changes on the Interferometric Synthetic Aperture Radar (InSAR) coherence and closure phase to determine whether the InSAR coherence and closure phase can be used to estimate soil moisture changes. We generated semi-synthetic multi-looked interferograms by pairing n real single-looked pixels of an observed SAR image with n synthetic single-looked pixels. The synthetic SAR data are generated from the real SAR data by applying soil moisture changes with a pre-defined mean and standard deviation of changes. Our results show that the diversity of soil moisture changes within the multi-look window gives rise to decorrelation, a multi-looked phase artifact, and a non-zero phase triplet. The decorrelation and closure phase increase by enlarging the diversity of soil moisture changes. We also showed that non-soil moisture changes can lead to larger decorrelations and closure phases. Furthermore, the diversity of phase changes, decorrelation, and closure phases are correlated with land cover type. We concluded that the closure phase and coherence are independent of the magnitude of soil moisture changes and are inappropriate tools to estimate soil moisture changes. Coherence, however, can be used as a proxy for soil moisture changes if the diversity and magnitude of soil moisture changes within a multi-looked pixel are strongly correlated.

Changes in agricultural water demands and soil moisture in China over the last half-century and their effects on agricultural production

As the mulching practice in pineapple culture in Hawaii has developed over the last 50 years, a number of functions have been assigned to the action of the mulch. This study gives primary consideration to the effect of soil moisture and soil temperature changes upon pineapple growth. Soil moisture changes were determined from field samplings and lysimeter studies at Wahiawa, Oahu. Changes in the soil moisture budget with the mulch were so slight that the variability of field sampling precluded assessment without excessive replication. Coefficients of variability for samples taken at the plant butt were 3 to 5% of a moisture constant (e.g., 15‐bar point) for a soil series or within a single field. Moisture use, measured by semicontained hydraulic lysimeters, was reduced by the mulch when the soil was very wet but changed little when the soil moisture ranged from field capacity (0.15‐bar) to the 15‐bar point. The mulch raised the average soil temperature about 1.6C during the winter. The measured one‐third increase in the plant growth was nearly identical with the increase calculated from the growth‐response of pineapple to temperature.

Triangle of Environment, Water and Energy: A Sociological Appraisal

<p>Peatlands comprise 19% of the permafrost area in the subarctic zone, they store 277 Pg of organic carbon. Peatlands in that area are represented by palsa mire. The palsa mire consists of frozen peat mounds (palsa), thermokarst depression and the wet bog without permafrost.</p><p>Climate change and thawing of permafrost leads to a change in soil moisture, both drying and wetting. This can lead to a change in the carbon balance of the ecosystem and increase or decrease the emission of greenhouse gases (CO<sub>2</sub> and CH<sub>4</sub>).</p><p>The aim of the work was to study the effect of changes in soil moisture on the biological activity of palsa mire peat soils in the north of Western Siberia (65°18'52"N, 72°52'32"E). The studies were conducted in 2018-2021 in the northern taiga in the discontinuous permafrost zone.</p><p>The two palsas (Cryic Histosol) and the surrounding bog (Fibric Histosol) were examined. Palsa soils were characterized by high variability of the studied parameters; active layer thickness was 0.66±0.07 m, soil moisture - 30.98±2.49%, soil temperature - 8.31±0.45°C. The soils of the bog were characterized by the absence of permafrost, a higher soil temperature - 13.58±0.26°C and soil moisture - 74.59±0.26%. Despite the difference in the studied parameters of these ecosystems, no significant differences in biological activity were found (185.97±30.51 mgCO<sub>2</sub>/m<sup>2</sup>/h).</p><p>Based on field measurements, 3 plots were identified with the same type of vegetation and soil temperature, but significantly differ in soil moisture. Depending on soil moisture, the plots were named “Dry” (25.73±1.89%), “Wet” (38.44±0.70%) and “Moist” (53.09±1.06%). Biological activity did not vary significantly between the studied sites but had a multidirectional dynamic in different years. This shows the complexity of palsa, their multifactorial nature and an ambiguous response to changes in moisture.</p><p>An added experiment was set up to change soil moisture - transplantation. Measured of CO<sub>2</sub> emissions from undisturbed peat soil of a large volume transferred from dry palsa to a wetting bog. And vice versa. The biological activity of the soils did not differ considerable both during wetting and draining. In different years, there was a vary dynamics in CO<sub>2</sub> emissions.</p><p>According to the results of the study, with climate change, thawing of permafrost and palsa degradation, there will be no significant CO<sub>2 </sub>flux. This may be due to the multifactorial nature of ecosystems, a wide optimum of soil moisture for peat soils. The influence of additional factors is also significant: the size of the methanotrophic barrier, the transport of CO<sub>2</sub> with solutions over the surface of the palsa permafrost.</p>

Soil moisture drives microbial controls on carbon decomposition in two subtropical forests

AimClimate change results in increasing temperature and modified precipitation regimes in the High Arctic. Models can help anticipate the consequences on future biotic dynamics, e.g. vegetation. In rugged terrain, forecasts should consider fine‐scale spatial variability in environmental conditions that are proximally linked to plant performance. Here, we forecasted Arctic plant community response to future climate change using high‐resolution environmental variables.LocationZackenberg in the High Arctic of Greenland.MethodsUsing a combination of remote‐sensing data and field measurements, we interpolated soil moisture and temperature at 1 m resolution together with spatial data on snow cover and solar radiation. We calibrated stacked species distribution models (S‐SDMs) with data from 200 vegetation plots. To explore the sensitivity of Arctic communities to climate change, we forecasted these models under simulated increases in temperature and changes (positive or negative) in snow cover and soil moisture, corresponding to more winter and/or summer precipitation and higher frequencies of summer droughts.ResultsS‐SDMs associated with high‐resolution environmental variables were able to reproduce the spatial variation in species richness and plant community structure along a mountain slope in Zackenberg. Model forecasts under climate change revealed that most species reacted to a combination of changes in soil moisture and temperature, and changes in these two variables resulted in an extensive restructuring of the distributions of species assemblages. In most scenarios, a gradual homogenization of communities was forecasted due to shrub expansion.Main conclusionsIncreasing temperatures and altered soil moisture were predicted to turn the currently highly heterogeneous tundra landscape at Zackenberg into homogenous dwarf‐shrub tundra. Such homogenization of vegetation communities may have profound ramifications for species, interaction webs, and ecosystem processes via modifications to the surface albedo, energy and water balance, as well as snow accumulation and permafrost.

Contributions of changes in soil moisture to the projected climate change in the tropics at the end of the twenty first century are quantified using the simulations from five different global climate models, which contributed to the GLACE–CMIP5 experiment. “GLACE” refers to the Global Land Atmosphere Coupling Experiment and “CMIP5” to the fifth phase of the Coupled Model Intercomparison Project. This is done by relating the overall projected changes in climate to those changes in climate that are related to the projected changes in soil moisture. The study focusses on two particular aspects of the interactions of the soil moisture with climate, the soil moisture–temperature coupling and the soil moisture–precipitation coupling. The simulations show distinct future changes in soil moisture content in the tropics, with a general tendency of increases in the central parts of the tropics and decreases in the subtropics. These changes are associated with corresponding changes in precipitation, with an overall tendency of an approximate 5 % change in soil moisture in response to a precipitation change of 1 mm/day. All five individual models are characterized by the same qualitative behaviour, despite differences in the strength and in the robustness of the coupling between soil moisture and precipitation. The changes in soil moisture content are found to give important contributions to the overall climate change in the tropics. This is in particularly the case for latent and sensible heat flux, for which about 80 % of the overall changes are related to soil moisture changes. Similarly, about 80 % of the overall near-surface temperature changes (with the mean temperature changes in the tropics removed) are associated with soil moisture changes. For precipitation, on the other hand, about 30–40 % of the overall change can be attributed to soil moisture changes. The robustness of the contributions of the soil moisture changes to the overall climate change varies between the different meteorological variables, with a high degree of robustness for the surface energy fluxes, a fair degree for near-surface temperature and a low degree for precipitation. Similar to the coupling between soil moisture and precipitation, the five individual models are characterized by the same qualitative behaviour, albeit differences in the strength and the robustness of the contributions of the soil moisture change. This suggests that despite the regional differences in the projected climate changes between the individual models, the basic physical mechanisms governing the soil moisture–temperature coupling and the soil moisture–precipitation coupling work similarly in these models. The experiment confirms the conceptual models of the soil moisture–temperature coupling and the soil moisture–precipitation coupling described Seneviratne et al. (Earth-Sci Rev 99:125–161, 2010). For the soil moisture–temperature coupling, decreases (increases) in soil moisture lead to increasing (decreasing) sensible heat fluxes and near-surface temperatures. The soil moisture–precipitation coupling is part of a positive feedback loop, where increases (decreases) in precipitation cause increases (decreases) in soil moisture content, which, in turn, lead to increasing (decreasing) latent heat fluxes and precipitation.

The effects of changes in soil moisture on nitrogen cycling in acid wetland types of the New Jersey Pinelands (USA)

Revealing the characteristics of soil moisture and temperature under typical sloping land uses in the loess hilly region is of great significance for the efficient and sustainable use of sloping land resources. In this study, the soil moisture content in the 0–160 cm soil layer and the soil temperature in the 0–100 cm soil layer under soybean sloping field, maize terraced field, jujube orchard, and grassland were continuously observed during the 2014 and 2015 growing seasons (May to October). Traditional statistical analysis and wavelet fractal dimension method were used to study the characteristics and complexity of soil moisture and temperature changes under different sloping land uses. The main findings are as follows: (1) Maize terraced field obtained high soil moisture content in the 0–160 cm soil layer, showing the outstanding effect of soil moisture conservation, especially in the drought growing season. Maize terraced field minimized the changing amplitude (Ka), variation degree (Cv), and active layer of soil moisture in the 0–160 cm soil layer and the Ka and Cv of soil temperature in the 0−100 cm soil layer. The maize terraced field had the minimum fractal dimensions of soil moisture and temperature both in normal precipitation and drought growing seasons, indicating that the maize terraced field minimized the complexity of soil moisture and temperature changes. (2) The jujube orchard obtained the minimum soil moisture content in the 0−160 cm soil layer, and greatly increased the Ka, Cv, and active layer of soil moisture both in normal precipitation and drought growing seasons. The jujube orchard obtained the maximum soil temperature in the 0–100 cm soil layer, and greatly increased the Ka and Cv of soil temperature. The jujube orchard also had the maximum fractal dimensions of soil moisture and temperature, indicating that soil moisture and temperature changes in jujube orchard were the most complex. (3) Compared to jujube orchard, soybean sloping field and grassland increased soil moisture content, reduced the Ka and Cv of soil moisture and temperature, and weakened the complexity of soil moisture and temperature changes. (4) The analysis results of the complexity of soil moisture and temperature changes under the experimental sloping land uses based on the wavelet fractal dimension method were consistent with the traditional statistical analysis results, indicating that it is feasible to evaluate the complexity of soil moisture and temperature changes under the typical sloping land uses in the loess hilly region by using wavelet fractal dimension method. In summary, terraced fields were conducive to improving soil moisture content and maintaining the stability of soil moisture and temperature. It is recommended that the project of changing sloping fields into terraced fields should be popularized in the loess hilly region to effectively utilize limited natural precipitation. In order to prevent the jujube orchard from degenerating and dying due to long-term drought and water shortage, effective water management measures need to be taken to achieve the sustainable development of dry farming jujube orchard.