Rock phosphate is a non-renewable primary source for mineral phosphorus (P) fertilizers that intensive agriculture is highly dependent on. To avoid P fertilizer shortages and limit negative environmental impacts, circular economy approaches are needed with recycling-derived fertilizer (RDF) applications. Here, a grassland field trial was established with two struvites (potato wastewater, municipal wastewater) and two ashes (poultry-litter ash, sewage-sludge ash) at a P application rate of 40 kg P ha(-1) (replicates n = 5). The impact of these RDFs on the soil microbial P cycling community was compared to conventional mineral P-fertilizer and a P-free control. Topsoil samples were taken directly after Lolium perenne grass cuts at months 3, 5 and 15. Cultivable phosphonate and phytate utilizing bacteria, potential acid and alkaline phosphomonoesterase activity, and phoC and phoD copy numbers responded stronger to seasonal effects than treatment effects. No significant overall effect of the fertilizer application was detected in the beta-diversity of the bacterial and fungal communities after 15 months, but individual phylogenetic taxa were affected by the treatments. The ash treatments resulted in significantly higher relative abundance of Bacillota and Rokubacteria and lower relative abundance of Actinomycetota. Sewage-sludge ash had significantly lowest abundances of genera Bacillus and Bradyrhizobium that are well known for their P cycling abilities. The struvite RDFs either positively influenced the P cycling microbial community as demonstrated through higher tri-calcium phosphate solubilizing capabilities (month 3), or were similar to the superphosphate and P-free treatment. From a soil-microbial health perspective, the presented findings indicate that struvites are a suitable substitute for superphosphate fertilizers.

Biochar has been considered a promising material for soil carbon sequestration. However, there are huge knowledge gaps regarding the carbon reduction effects of biochar-plant-polluted soil. Here, rice straw biochar (RB) was applied in ryegrass-cadmium (Cd)-contaminated soil to investigate the full-cycle carbon dioxide (CO2) emission and intrinsic mechanism. RB resulted in a 37.00 %-115.64 % reduction in accumulative CO2 emissions and a 31.61 %-45.80 % reduction in soil bioavailable Cd throughout the whole phytoremediation period. CO2 emission reduction triggered by RB can be attributed to the regulation of plant and rhizosphere ecological functions. RB could bolster photosynthetic carbon fixation by maintaining the stability of the structure of the chloroplasts and thylakoids, accelerating the consumption of terminal photosynthate, upregulating photosynthetic pigments, and mitigating oxidative damage. Besides, RB reduced the metabolism of readily mineralizable carbon sources while reinforcing the utilization of certain nutrient substrates. Besides, the composition of rhizosphere microbial communities was altered, especially those associated with carbon cycling (Chloroflexi, Actinobacteriota, and Acidobacteriota phyla) to orient soil microbial evolution to lower soil CO2 emission. This study aims to establish a win-win paradigm of carbon reduction-pollution alleviation to deepen the understanding of biochar in carbon neutrality and soil health and provide a theoretical basis for field pilot-scale studies.

Soil freeze-thaw state influences multiple terrestrial ecosystem processes, such as soil hydrology and carbon cycling. However, knowledge of historical long-term changes in the timing, duration, and temperature of freeze-thaw processes remains insufficient, and studies exploring the combined or individual contributions of climatic factors-such as air temperature, precipitation, snow depth, and wind speed-are rare, particularly in current thermokarst landscapes induced by abrupt permafrost thawing. Based on ERA5-Land reanalysis, MODIS observations, and integrated thermokarst landform maps, we found that: 1) Hourly soil temperature from the reanalysis effectively captured the temporal variations of in-situ observations, with Pearson' r of 0.66-0.91. 2) Despite an insignificant decrease in daily freeze-thaw cycles in 1981-2022, other indicators in the Qinghai-Tibet Plateau (QTP) changed significantly, including delayed freezing onset (0.113 d yr- 1), advanced thawing onset (-0.22 d yr- 1), reduced frozen days (-0.365 d yr- 1), increased frozen temperature (0.014 degrees C yr- 1), and decreased daily freeze-thaw temperature range (-0.015 degrees C yr- 1). 3) Total contributions indicated air temperature was the dominant climatic driver of these changes, while indicators characterizing daily freeze-thaw cycles were influenced mainly by the combined effects of increased precipitation and air temperature, with remarkable spatial heterogeneity. 4) When regionally averaged, completely thawed days increased faster in the thermokarstaffected areas than in their primarily distributed grasslands-alpine steppe (47.69%) and alpine meadow (22.64%)-likely because of their stronger warming effect of precipitation. Locally, paired comparison within 3 x 3 pixel windows from MODIS data revealed consistent results, which were pronounced when the thermokarst-affected area exceeded about 38% per 1 km2. Conclusively, the warming and wetting climate has significantly altered soil freeze-thaw processes on the QTP, with the frozen soil environment in thermokarstaffected areas, dominated by thermokarst lakes, undergoing more rapid degradation. These insights are crucial for predicting freeze-thaw dynamics and assessing their ecological impacts on alpine grasslands.

Photovoltaic panels (PVPs) in grasslands are arranged in such a way that they capture rainfall, which subsequently drips from the edges and causes splash erosion in the grassland, ultimately destroying the natural ecological environment. As such, PVPs can adversely affect fragile saline-alkali habitats, but the precise ecological impact of PVP-caused rainfall splash erosion on saline-alkali grassland has yet to be quantified. To explore the impact of splash erosion on the saline-alkali grassland under PVPs, an investigation was performed here on various surfaces commonly underneath PVPs. These surfaces were typical bare saline-alkali surface (B), Suaeda glauca surface (S) and Leymus chinensis surface (L), and all were positioned under PVPs in the Songnen Plain saline-alkali grassland. The soil splash erosion ditch morphology, the plant community status, and the field-measured soil properties of the three underlying surfaces were all analyzed as part of this investigation in accordance with the observed impact of splash erosion on the three underlying surface ecosystems. Ultimately, the splash erosion generated four ditches in the underlying surfaces, with the degree of soil loss ranked from greatest to smallest as B > S > L. According to the RDA results, vegetation coverage was the main factor affecting splash ditch morphology. The vegetation of the S. glauca surface was fragmented following splash erosion. Much of the S. glauca in the splash erosion ditch died, resulting in a 33.47 %-64.66 % reduction in coverage. In contrast, L. chinensis maintained a higher coverage, which means that it inhibited splash erosion more effectively. For the bare surface, the rainfall splash reduced pH and Ec, and S. glauca began to grow along the edge of the ditch. Collectively, our study quantified the impact of rain splash erosion under PVPs in a saline-alkali grassland ecosystem, comparing the difference in the degree of splash erosion among three different underlying surfaces.

The sustained intensification of agricultural production to meet increasing food, feed and fibre demands has aggravated soil deformation, thereby accelerating soil degradation. The conversion of some of these degraded arable lands to permanent grassland has been recommended to recover the soil functions. However, there is still a considerable gap in understanding the timeline for the effective recovery of degraded land in terms of its stability (resistance and resilience to disturbance). Moreover, the dynamics of the recovery process in ameliorative grasslands are still not fully understood. In this study, the physical, hydraulic, and mechanical properties including the coefficient of compressibility (Cn) and precompression stress were investigated in degraded arable land at three different depths (0-5, 10-15 and 20-25 cm) after 1-, 2-, 8-, 13-, 19-, and 25-years ameliorative grassland conversion. To fully understand and finalise the dynamics of the recovery process as a function of time since the amelioratory conversion, we combined the analysed data from 2 different sets of measurements (loading conditions) on samples predrained to - 60 hPa matric potential. The loading conditions were (a). static confined compression with normal stresses applied for 4 h in steps of 1, 20, 50, 100, 200, and 400 kPa without stress relaxation on each sample, and (b). dynamic - cyclic loading at 50 kPa with 30 seconds of loading and unloading (relaxation). We included data concerning porewater pressure dynamics under the cyclic loading condition to document possible changes in elasticity. Our results showed that settlement during loading and the elastic rebound during unloading were related to the sward age and the sampled depth. Before the cyclic loading experiment, higher values of effective stress were recorded in the older swards, but the values changed after loading in response to the change in the porewater pressure. The effective stress values were less negative during loading than when unloading. At soil depth of 0-5 cm in the 25 years old sward, the rebound rate (values) and the coefficient of compressibility were higher due to changes in soil properties, particularly the soil bulk density, while at the 10-15 and 20-25 cm depths, the mean values were much closer. When the rebound rate was considered, the highest mean value occurred at 13 years after conversion. In addition, significantly higher values of pre-compression stress were observed in the 8-year-old sward under static loading, which decreased by 19 years. Higher values of pre-compression stress were mostly recorded at the lower depths under static loading. Finally, the results showed that a period between 8 and 13 years is needed to document the starting of strength regain and the recovery of the physical properties and functions, after conversion to grassland. This recovery was observed even up to deeper depths of 20-25 cm for precompression stress and for the soil compressibility/ rebound in the top 5 cm

Surface soil cracking in alpine meadows signifies the transition of degradation from quantitative accumulation to qualitative deterioration. Quantitative research remains insufficient regarding changes in the mechanical properties of degraded meadow soils and the mechanical thresholds for cracking initiation. This study explored the relationships between surface cracking and the physical properties, tensile strength, and matrix suction of root-soil composites in alpine meadow sites with different stages of degradation (undegraded (UD), lightly degraded (LD), moderately degraded (MD), and heavily degraded (HD)) under different water gradients (high water content (HWC), medium water content (MWC), and low water content (LWC)) corresponding to different drying durations at a constant temperature of 40.0 degrees C. The Huangcheng Mongolian Township in Menyuan Hui Autonomous County, Qinghai Province, China was chosen as the study area. The results indicated that as the degradation degree of alpine meadow intensified, both water content of root-soil composite and the fine grain content of soil decreased. In contrast, the root-soil mass ratio and root area ratio initially increased and then decreased with progressive degradation. Under a consistent water content, the tensile strength of root-soil composite followed a pattern of MD>HD>LD>UD. The peak displacement of tensile strength also decreased as the degradation degree of alpine meadow increased. Both the tensile strength and matrix suction of root-soil composite increased as root-soil water content decreased. A root-soil water content of 30.00%-40.00% was found to be the critical threshold for soil cracking in alpine meadows. Within this range, the matrix suction of root-soil composite ranged from 50.00 to 100.00 kPa, resulting in the formation of linear cracks in the surface soil. As the root-soil water content continued to decrease, liner cracks evolved into branch-like and polygonal patterns. The findings of this study provide essential data for improving the mechanical understanding of grassland cracking and its development process.

The importance of green areas in today's modern city concept is increasing day by day. In this understanding, the use of turfgrass [e.g. Bentgrass (Agrostis spp. L.); Kentucky Bluegrass (Poa pratensis L.); Common Bermudagrass Cynodon dactylon (L.) Pers. (Poales: Poaceae)] in sports fields is getting important. Golf courses mainly occurs turfgrass and not much nematological studies has been done in courses of T & uuml;rkiye. In this study, total of 51 soil and 3 water samples were taken from golf courses in Antalya, T & uuml;rkiye's largest golf tourism destination, in 2021. Within the scope of this study, plant parasitic nematode (PPN) species belonging to the genera Aphelenchoides Fischer, 1894 (Tylenchida: Aphelenchoididae), Aphelenchus Bastian, 1865 (Tylenchida: Aphelenchoididae), Criconemella (De Grisse & Loof, 1965) (Tylenchida: Criconematidae), Ditylenchus Filipjev, 1936 (Tylenchida: Anguinidae), Helicotylenchus Steiner, 1945 (Tylenchida: Hoplolaimidae), Hemicriconemoides Chitwood & Birchfield, 1957 (Tylenchida: Criconematidae), Hemicycliophora de Man, 1921 (Tylenchida: Hemicycliophoridae), Hoplolaimus von Daday, 1905 (Tylenchida: Hoplolaimidae), Longidorus Micoletzky, 1922 (Dorylaimida: Longidoridae), Paratrichodorus Siddiqi, 1974 (Triplonchida: Trichodoridae) and Tylenchus Bastian, 1865 (Tylenchida: Tylenchidae) were identified using morphological and morphometric methods. The most detected species in the samples was Hemicycliophora punensis Darekar & Khan, 1980 (Rhabditida: Hemicycliophoridae) (22.22%), while the least detected PPN species was Helicotylenchus dihystera (Cobb, 1893) Sher, 1961 (Tylenchida: Hoplolaimidae) (3.70%). In this study, it is important there are virus vector species among the identified plant parasitic nematode genera. These nematode species can play an active role in the spread of various viral diseases in turfgrass areas. In turfgrass areas where very sensitive cultivation is carried out, such as golf courses, PPN's cause direct damages by feeding, which serve as the source of entry of pathogens into the plants. This situation increases the prevalence and severity of the disease in infected fields. Therefore, early detection of the presence of PPN's in cultivation areas is important to determine effective control strategies.

Wild boar ( Sus scrofa ) is a widespread megaherbivore that can intensively disturb large areas of its habitat both in its native and non-native ranges, when populations reach high densities. The main problem is its rooting habit, which entails intensive disturbance of the topsoil and herbaceous layer. The extent of concomitant habitat degradation varies across ecoregions; some ecosystems are rather resilient, although the damages are long-lasting in others. In mown meadows, a secondary problem is the inability to resume mowing due to the uneven soil surface of rooted patches. This can lead to both economic loss and a loss of management-dependent biodiversity. We assessed the short-term effects of rooting on vegetation cover and composition in central European permanent hay meadows and tested the utility of manual soil surface resmoothing to enable the continuation of mowing. We found that rooting increased bare soil surface but vegetation recovery occurred within a year. Similarly, high resilience was found for species composition. We could not detect any difference between rooted and intact grassland patches after 1 yr. This short-term perturbation of the composition could be associated with a temporary decrease in grassland specialist species and an increase in ruderal and pioneer species. Soil surface resmoothing was an additional disturbance, but vegetation cover returned to the level of intact grasslands within a year. Vegetation composition needed a slightly longer time (2 yr) to recover than that without resmoothing. We thus recommend the application of manual resmoothing in hay meadows with high short-term resilience to rooting, but a risk of long-term degradation (e.g., shrub encroachment) if mowing is not resumed. In hay meadows with lower resilience (because of, e.g., steep slopes), resmoothing should be applied with caution and may be supplemented with seeding to support the recovery of the vegetation and prevent soil erosion. (c) 2025 The Society for Range Management. Published by Elsevier Inc. All rights are reserved, including

Forests and grasslands often occur side by side in the landscape, forming a complex mosaic system with contrasting environmental conditions, maintained by different fire-vegetation stabilising feedbacks. Woody species that occur along this sharp gradient must adopt viable ecological strategies to deal with the contrasting environments of these ecosystems. For this, plants are challenged to efficiently coordinate the functioning of ecological strategy dimensions above- and below-ground. We tested hypotheses related to structural changes in vegetation and associated shifts in community-level trait patterns and ecological strategies during woody plant encroachment. We surveyed 60 permanent plots in forest-grassland mosaics at two different times (2012-2022) to obtain data on changes in vegetation structure, species composition, abundance and ecological strategies after 10 years without disturbance, capturing a gradient from open and woody plant-encroached grasslands to closed forests. An integrated functional approach was used to assess the different dimensions of plant trait variation, including 10 above- and below-ground traits, representing whole-plant, leaf, stem and root strategies. Woody plant encroachment led to a substantial increase in woody plant density in former grasslands, transforming their structure to resemble that of young forests. Interestingly, we found clear trade-offs between above- and below-ground traits among woody species. On the one hand, the species occurring in grassland had conservative leaves, a strategy for protection against high solar incidence, physical damage and drought, and had roots with a 'do-it-yourself' strategy, which ensures efficiency in the acquisition of nutrients and water in nutrient-limited soils, and had thick bark related to fire resistance. On the other hand, forest species were usually taller and had acquisitive leaves, indicating highly competitive ability in light-limited forests, whereas their roots had an 'outsourcing' strategy of resource uptake to mycorrhizal fungi in the nutrient-rich soils of forests. Synthesis: We advanced the current understanding of woody plant encroachment in grasslands by showing the underlying trait-based trade-offs that enable woody species to occur along the transition between forest and grassland through space and time. Importantly, we have shown how below-ground traits are important in explaining the species strategies, with a negative covariance between above- and below-ground. Our integrative trait-based approach will be helpful in better understanding and managing forest-grassland mosaics in southern Brazil and analogous patchy ecosystems around the world. Florestas e campos frequentemente ocorrem lado a lado na paisagem, formando um sistema mosaico complexo com condiçõ es ambientais contrastantes, mantido por diferentes feedbacks estabilizadores entre fogo e vegetaçã o. Espé cies lenhosas que ocorrem ao longo desse acentuado gradiente devem adotar estraté gias ecoló gicas viá veis para lidar com os ambientes contrastantes desses ecossistemas. Para isso, as plantas precisam coordenar eficientemente o seu funcionamento acima e abaixo do solo. No presente artigo nó s avaliamos mudanç as estruturais na vegetaçã o associadas com mudanç as funcionais na escala de comunidades e nas estraté gias ecoló gicas das espé cies durante o processo de adensamento de espé cies lenhosas. Para isso, realizamos a amostragem de 60 parcelas permanentes localizadas nos mosaicos campo-floresta, em dois perí odos de tempo (2012 e 2022). O objetivo foi de obter dados sobre mudanç as na estrutura da vegetaçã o, composiçã o de espé cies, abundâ ncia e estraté gias ecoló gicas apó s 10 anos sem distú rbios, capturando um gradiente que vai de campos abertos, campo adensado por plantas lenhosas até florestas fechadas. Utilizamos uma abordagem funcional integrada para aavaliar as diferentes dimensõ es funcionais das plantas, incluindo 10 atributos funcionais acima e abaixo do solo (incluindo atributos de folha, caule e raiz). O adensamento de espé cies lenhosas resultou em um aumento substancial na densidade de plantas lenhosas em á reas anteriormente ocupadas por campos, transformando sua estrutura que atualmente se assemelha à de florestas jovens. Curiosamente, identificamos claros trade-offs entre atributos funcionais acima e abaixo do solo em espé cies lenhosas. Por um lado, as espé cies ocorrendo em campos apresentaram folhas conservativas, uma estraté gia para proteçã o contra alta incidê ncia solar, danos fí sicos e seca, alé m de raí zes com uma estraté gia 'faç a você mesmo', garantindo eficiê ncia na aquisiçã o de nutrientes e á gua em solos pobres, e casca espessa relacionada à resistê ncia ao fogo. Por outro lado, espé cies de floresta foram geralmente mais altas e apresentaram folhas aquisitivas, indicando alta competitividade onde existe limitaçã o de luz, enquanto suas raí zes exibiram uma estraté gia de aquisiçã o de recursos mediada por fungos micorrí zicos, no ambiente onde os solos sã o mais ricos. Sí ntese. Avanç amos no entendimento atual sobre o adensamento de espé cies lenhosas sobre os campos ao demonstrar os trade-offs funcionais que permitem a ocorrê ncia de espé cies lenhosas ao longo da transiçã o entre floresta e campo no espaç o e no tempo. Mostramos, especialmente, como atributos funcionais abaixo do solo sã o importantes para explicar as estraté gias das espé cies, com uma covariâ ncia negativa entre atributos funcionais acima e abaixo do solo. Nossa abordagem integrativa baseada em atributos foi ú til para um melhor entendimento e manejo de mosaicos floresta-campo no sul do Brasil e em ecossistemas aná logos ao redor do mundo.

Freeze-thaw-induced N2O pulses could account for nearly half of annual N2O fluxes in cold climates, but their episodic nature, sensitivity to snow cover dynamics, and the challenges of cold-season monitoring complicate their accurate estimation and representation in global models. To address these challenges, we combined in situ automated high-frequency flux measurements with cross-ecoregion soil core incubations to investigate the mechanisms driving freeze-thaw-induced N2O emissions. We found that deepened snow significantly amplified freeze-thaw N2O pulses, with these similar to 50-day episodes contributing over 50% of annual fluxes. Additionally, freeze-thaw-induced N2O pulses exhibited significant spatial heterogeneity, ranging from 3.4 to 1184.1 mu g N m(-2) h(-1) depending on site conditions. Despite significant spatiotemporal variation, our results indicated that 68%-86% of this variation can be explained by shifts in controlling factors: from water-filled pore space (WFPS), which drove anaerobic conditions, to microbial constraints as snow depth increases. Below 43% WFPS, soil moisture was the overwhelmingly dominant driver of emissions; between 43% and 66% WFPS, moisture and microbial attributes (including denitrifying gene abundance, nitrogen enzyme kinetics, and microbial biomass) jointly triggered N2O emissions pulses; above 66% WFPS, microbial attributes, particularly nitrogen enzyme kinetics, prevailed. These findings suggested that maintaining higher soil moisture served as a trigger for activating microbial activity, particularly enhancing nitrogen cycling. Furthermore, we showed that hotspots of freeze-thaw-induced N2O emissions were linked to high root production and microbial activity in cold and humid grasslands. Overall, our study highlighted the hierarchical control of WFPS and microbial processes in driving freeze-thaw-induced N2O emission pulses. The easily measurable WFPS and microbial attributes predictable from plant and soil properties could forecast the magnitude and spatial distribution of N2O emission hot moments under changing climate. Integrating these hot moments, particularly the dynamics of WFPS, into process-based models could refine N2O emission modeling and enhance the accuracy of global N2O budget prediction.