Aridification Inhibits the Release of Dissolved Organic Carbon from Alpine Soils in Southwest China

Soil Systems, Год журнала: 2025, Номер 9(1), С. 24 - 24

Опубликована: Март 6, 2025

The alpine peatlands in western Sichuan Province are currently experiencing aridification. To understand the effects of aridification on characteristics organic carbon release from soils, soil northwest Plateau was investigated. Soil columns were incubated under different moisture conditions situ and laboratory, ultraviolet-visible absorption spectroscopy three-dimensional fluorescence used to assess dissolved (DOC) levels. results revealed that (1) cumulative DOC decreased with decreasing content. laboratory (0–5 cm reached 1.93 ± 0.43 g/kg) greater than 1.40 0.13 g/kg); (2) 0–5 exhibited greatest response changes water content, layer (1.40 5–15 (1.25 0.03 (3) UV-visible spectra 3D spectral indicated increases content chromophoric matter (CDOM) components strong hydrophobicity, especially tyrosine (surface increased 39.59~63.31%), DOC. This increase hydrophobic CDOM enhances aromaticity degree humification Our drought inhibits DOC, which is unfavorable for sequestration potentially resulting loss pools further degradation ecosystem functions.

Язык: Английский

---

Responses of alpine grassland plant communities on Sejila Mountain in the Qinghai-Tibet Plateau to phosphorus addition

Frontiers in Environmental Science, Год журнала: 2025, Номер 13

Опубликована: Май 22, 2025

Introduction As an important global ecological security barrier, the Qinghai-Tibet Plateau is a key region for exploring how climate change affects grassland ecosystem. Therefore, this study explored mechanism of impact intensified atmospheric Phosphorus (P) deposition on alpine plant communities in Sejila Mountain, Nyingchi, Tibet. Methods A field experiment with four different gradients phosphate fertilizer application (0, 50, 75, and 100 kg hm −2 −1 ) was designed. The variation patterns morphology, biomass, nutrient content, stoichiometric ratio characteristics response to P were systematically analyzed. Results addition significantly affected total community biomass root-shoot ratio, showing trend initial increase followed by decline (P < 0.05). Additionally, influenced traits (average height, coverage, abundance) aboveground (Poaceae, Cyperaceae, Forbs). Poaceae Forbs increased increasing levels. At , these parameters observed. coverage Cyperaceae plants showed significant downward trend. had limited effects carbon (C) nitrogen (N) contents their respective ratios. However, it both belowground parts 0.05), consequently reducing C:P N:P ratios plants. This effectively enhanced use efficiency. Discussion highlights role shaping structure cycling grasslands. excessive may exacerbate competition among plants, potentially leading nutritional imbalances soil environmental degradation.

Язык: Английский

---

Divergent seasonal responses of above- and below-ground to environmental factors in alpine grassland

Frontiers in Plant Science, Год журнала: 2023, Номер 13

Опубликована: Фев. 6, 2023

Under current global warming, the relationship between season changes of plants and environmental factors is focused on high-elevation latitude regions. Due to desynchronized growth above- below-ground buffering soil, driving in leaf root show seasonal dynamics.We measured intensity alpine steppe over non-growing (October-April) growing (May-September). Air temperature, precipitation, soil moisture, temperature were used analyze correlation based rhythm.Results showed that an earlier spring a delayed dormancy autumn than was observed. Our results strongly suggest moisture plays more important role unfolding while consistent with withering shoots. Soil comes from melt phenology roots, which derived storage subsoil layer last autumn.Climate change will affect strong patterns characterized these precipitation-limited systems, especially fall shoulder seasons. As seasonality steppe, divergent responses fine would be explored.

Язык: Английский

---

Distinct responses of soil bacterial communities to N and P fertilization in a Tibetan alpine meadow of China

Land Degradation and Development, Год журнала: 2023, Номер 34(14), С. 4236 - 4251

Опубликована: Июнь 24, 2023

Abstract Increased nitrogen (N) and phosphorus (P) availability, due to fertilization deposition, is expected influence soil microbial community structure function. However, little known about the sensitivity dependency of on levels N P, integration P inputs in alpine meadow ecosystems. Here, we implemented a 3‐year manipulative study with four (0, 10, 20, 30 g m −2 ) fertilization, NP (N at ratio 1:1) Tibetan meadow. We examined how greater availability affected bacterial diversity, top‐ (0–10 cm) sub‐top (10–20 soil, network topological properties, potential mechanisms behind them. Although α β diversities bacteria within sub‐topsoil were not significantly different from those control across N, levels, changed relative abundances more phyla than did separately. Furthermore, N10 N20 treatments strengthened interactions, whereas affect complexity connectivity co‐occurrence network. In addition, mechanism structuring for separate differed that fertilization. The application composition mainly through changes total available respectively, shifted decreasing plant species richness. These findings provide quantification response diversity It also suggests meadow, communities may alter their fitness according oligotrophic/copiotrophic taxa, rather changing diversity.

Язык: Английский

---

History of alpine grassland studies and management

Elsevier eBooks, Год журнала: 2024, Номер unknown, С. 33 - 65

Опубликована: Дек. 4, 2024

Язык: Английский

---

A Hierarchical Machine Learning-Based Strategy for Mapping Grassland in Manitoba’s Diverse Ecoregions

Remote Sensing, Год журнала: 2024, Номер 16(24), С. 4730 - 4730

Опубликована: Дек. 18, 2024

Accurate and reliable knowledge about grassland distribution is essential for farmers, stakeholders, government to effectively manage resources from agro-economical ecological perspectives. This study developed a novel pixel-based classification approach using three supervised machine learning (ML) algorithms, which were assessed in the province of Manitoba, Canada. The process involved stages: (1) distinguish between vegetation non-vegetation covers, (2) differentiate non-grassland landscapes, (3) identify specific classes (tame, native, mixed grasses). Initially, this investigated different satellite data, such as Sentinel-1 (S1), Sentinel-2 (S2), Landsat 8 9, individually combined, random forest (RF) method, with best performance at first two steps achieved combination S1 S2. was then utilized conduct support vector (SVM) gradient tree boosting (GTB). In step 3, after filtering out pixels, RF, SVM, GTB classifiers evaluated combined S2 data types. Eighty-nine multitemporal raster-based variables, including spectral bands, SAR backscatters, digital elevation models (DEM), input ML models. RF had highest accuracy 69.96% overall (OA) Kappa value 0.55. After feature selection, variables reduced 61, increasing OA 72.62% 0.58. ranked second, its values improving 67.69% 0.50 72.18% 0.58 selection. impact raster quality on through multisensor image fusion. Grassland Hue, Saturation, Value (HSV) fused images showed higher (59.18%) (0.36) than Brovey Transform (BT) non-fused images. Finally, web map created show results within Soil Landscapes Canada (SLC) polygons, relating soil landscapes providing valuable information decision-makers researchers. Future work may include extending current methodology by considering other influential like meteorological parameters or properties, create comprehensive inventory across whole Prairie ecozone

Язык: Английский

---

Alpine steppe degradation: status, causes, and trends

Elsevier eBooks, Год журнала: 2024, Номер unknown, С. 87 - 102

Опубликована: Дек. 4, 2024

---