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How grasses stabilize soil organic carbon in aggregates of semi-arid ecologically restored land: Evidence from 13C natural abundance

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108627

Vikas Kumar Singhal , Avijit Ghosh , Amit K. Singh , Yogeshwar Singh , Siddhartha Sankar Biswas , Deepak Ojha , Ranjan Bhattacharyya

Land restoration with grasses is suitable for boosting soil organic carbon (SOC) and biomass productivity. For developing better restoration policies to preserve or increase SOC stock and ecosystem function, a deeper knowledge on the impact of various grasses on SOC dynamics in restored land is required. Here, long-term SOC sequestration was assessed by investigating aggregate-associated carbon (C) and ¹³C natural abundance following land restoration with Cenchrus ciliaris, Panicum maximum, Chrysopogon fulvus, Heteropogon contortus, Sehima nervosum, and Vetiveria zizanioides grasses in semi-arid India. Among the grasses, C. ciliaris, H. contortus, and S. nervosum improved the proportion of large macroaggregates from 5 to 21 % at the surface and from 1.7 to 12.3 % in the subsurface layer, while the proportion of microaggregates declined significantly (P < 0.05). The higher δ¹³C values of small macroaggregates (SM) indicated greater C stabilization within the microaggregates under all grasses. The SM could protect ∼22–33 % and 8–15 % of total SOC in land restored with C. ciliaris, H. contortus, and S. nervosum at the surface and the subsurface soil, respectively. However, the roots of C. ciliaris, H. contortus, and S. nervosum contributed to ∼12.66–13.75 % and 2.22–11.24 % of SOC in those layers, respectively. The direction of C transfer was from macroaggregates to microaggregates in soils under C. cilirais, S. nervosum, and H. contortus. This C flow direction could explain greater SOC stabilization than other grasses. The greater amount of aggregate-protected C under these grasses was linked to their greater root biomass, density, and decay rate. In contrast, C transfer from microaggregates to macroaggregates under P. maximum, C. fulvus, and V. zizanioides could result in poor C stabilization. Thus, C. ciliaris, H. contortus, and S. nervosum could be potential options for SOC sequestration in semi-arid ecosystems.

{"title":"How grasses stabilize soil organic carbon in aggregates of semi-arid ecologically restored land: Evidence from 13C natural abundance","authors":"Vikas Kumar Singhal , Avijit Ghosh , Amit K. Singh , Yogeshwar Singh , Siddhartha Sankar Biswas , Deepak Ojha , Ranjan Bhattacharyya","doi":"10.1016/j.catena.2024.108627","DOIUrl":"10.1016/j.catena.2024.108627","url":null,"abstract":"<div><div>Land restoration with grasses is suitable for boosting soil organic carbon (SOC) and biomass productivity. For developing better restoration policies to preserve or increase SOC stock and ecosystem function, a deeper knowledge on the impact of various grasses on SOC dynamics in restored land is required. Here, long-term SOC sequestration was assessed by investigating aggregate-associated carbon (C) and <sup>13</sup>C natural abundance following land restoration with <em>Cenchrus ciliaris</em>, <em>Panicum maximum</em>, <em>Chrysopogon fulvus</em>, <em>Heteropogon contortus</em>, <em>Sehima nervosum</em>, and <em>Vetiveria zizanioides</em> grasses in semi-arid India. Among the grasses, <em>C. ciliaris</em>, <em>H. contortus</em>, and <em>S. nervosum</em> improved the proportion of large macroaggregates from 5 to 21 % at the surface and from 1.7 to 12.3 % in the subsurface layer, while the proportion of microaggregates declined significantly (P < 0.05). The higher δ<sup>13</sup>C values of small macroaggregates (SM) indicated greater C stabilization within the microaggregates under all grasses. The SM could protect ∼22–33 % and 8–15 % of total SOC in land restored with <em>C. ciliaris</em>, <em>H. contortus</em>, and <em>S. nervosum</em> at the surface and the subsurface soil, respectively<em>.</em> However, the roots of <em>C. ciliaris</em>, <em>H. contortus</em>, and <em>S. nervosum</em> contributed to ∼12.66–13.75 % and 2.22–11.24 % of SOC in those layers, respectively. The direction of C transfer was from macroaggregates to microaggregates in soils under <em>C. cilirais</em>, <em>S. nervosum</em>, and <em>H. contortus.</em> This C flow direction could explain greater SOC stabilization than other grasses. The greater amount of aggregate-protected C under these grasses was linked to their greater root biomass, density, and decay rate. In contrast, C transfer from microaggregates to macroaggregates under <em>P. maximum</em>, <em>C. fulvus</em>, and <em>V. zizanioides</em> could result in poor C stabilization. Thus, <em>C. ciliaris</em>, <em>H. contortus</em>, and <em>S. nervosum</em> could be potential options for SOC sequestration in semi-arid ecosystems.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108627"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of sugarcane cultivation on the geochemistry of rare earth elements in Cretaceous rhyolite-derived soils, Northeastern Brazil

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2025.108700

Stephany Alves Brilhante , Ygor Jacques Agra Bezerra da Silva , Artur Henrique Nascimento Silva , Priscila Lira de Medeiros , Camila Victória da Silva Brazil , Clístenes Williams Araújo do Nascimento , Yuri Jacques Agra Bezerra da Silva , Rayanna Jacques Agra Bezerra da Silva , Tiago Osório Ferreira , Xosé Lois Otero , Marilya Gabryella Sousa , Valdomiro Severino Souza Junior

Rare earth elements (REEs) have recently been identified as emerging pollutants, with phosphate fertilizers representing a significant source of their introduction into agricultural soils. Brazil is the world’s foremost producer of sugarcane, the most prevalent agricultural crop in the Cabo Basin. Nevertheless, despite the region’s significance, no studies have yet addressed REE concentrations in the agricultural soils of this region. This research explored the geochemistry of rare earth elements (REEs) in rhyolite-derived soils that have been under intensive sugarcane cultivation since 1930 has resulted in soil contamination. Furthermore, the study examined the influence of soil properties on REE geochemistry. The higher concentration of REEs on the surface of soils under sugarcane cultivation, in comparison to the absence of REE enrichment in preserved areas, indicates that agricultural activities contribute to the accumulation of REEs in the Cabo Basin. Significant increases in the enrichment factors for Sm, La, Pr, Nd, Gd, Tb, Ho, Lu, and Y were observed in soils utilized for sugarcane cultivation. Cluster analysis effectively identified the enrichment of REEs in agricultural soils. The geochemical behavior of light rare earth elements (LREEs) was not influenced by soil properties. However, heavy rare earth elements (HREEs) demonstrated a robust positive correlation with pH, CEC, and OC. The chemical and mineralogical composition of the parent material exerts a pronounced influence on REE concentrations in the soils. These findings play a critical role in predicting and mitigating the prospective effects of REE accumulation due to agricultural activities and underscore the urgent necessity for specific legislation in Brazil to regulate REE levels in soils.

{"title":"Impact of sugarcane cultivation on the geochemistry of rare earth elements in Cretaceous rhyolite-derived soils, Northeastern Brazil","authors":"Stephany Alves Brilhante , Ygor Jacques Agra Bezerra da Silva , Artur Henrique Nascimento Silva , Priscila Lira de Medeiros , Camila Victória da Silva Brazil , Clístenes Williams Araújo do Nascimento , Yuri Jacques Agra Bezerra da Silva , Rayanna Jacques Agra Bezerra da Silva , Tiago Osório Ferreira , Xosé Lois Otero , Marilya Gabryella Sousa , Valdomiro Severino Souza Junior","doi":"10.1016/j.catena.2025.108700","DOIUrl":"10.1016/j.catena.2025.108700","url":null,"abstract":"<div><div>Rare earth elements (REEs) have recently been identified as emerging pollutants, with phosphate fertilizers representing a significant source of their introduction into agricultural soils. Brazil is the world’s foremost producer of sugarcane, the most prevalent agricultural crop in the Cabo Basin. Nevertheless, despite the region’s significance, no studies have yet addressed REE concentrations in the agricultural soils of this region. This research explored the geochemistry of rare earth elements (REEs) in rhyolite-derived soils that have been under intensive sugarcane cultivation since 1930 has resulted in soil contamination. Furthermore, the study examined the influence of soil properties on REE geochemistry. The higher concentration of REEs on the surface of soils under sugarcane cultivation, in comparison to the absence of REE enrichment in preserved areas, indicates that agricultural activities contribute to the accumulation of REEs in the Cabo Basin. Significant increases in the enrichment factors for Sm, La, Pr, Nd, Gd, Tb, Ho, Lu, and Y were observed in soils utilized for sugarcane cultivation. Cluster analysis effectively identified the enrichment of REEs in agricultural soils. The geochemical behavior of light rare earth elements (LREEs) was not influenced by soil properties. However, heavy rare earth elements (HREEs) demonstrated a robust positive correlation with pH, CEC, and OC. The chemical and mineralogical composition of the parent material exerts a pronounced influence on REE concentrations in the soils. These findings play a critical role in predicting and mitigating the prospective effects of REE accumulation due to agricultural activities and underscore the urgent necessity for specific legislation in Brazil to regulate REE levels in soils.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108700"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of erosive processes and erosion rate by in-situ measurements and multi-temporal TLS surveys in a mountainous badland area, Vallcebre (Spain)

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108622

Ona Torra , Càrol Puig-Polo , Marcel Hürlimann , Jérôme Latron

Badlands are highly erosive landforms characterized by dissected morphology, prevalent in regions with soft rocks and unconsolidated sediments, and are unsuitable for agriculture. Despite extensive research, understanding the dynamics of badlands remains limited, particularly in mountainous areas affected by freeze–thaw processes. This study aims to bridge this gap through a three-year investigation (November 2020 to November 2023), employing advanced geomatic techniques and a conventional approach. Focusing on two 8 m² and 12.5 m² badlands slopes facing north and south in the Upper Llobregat River Basin (Spain), the research aims to identify, characterize, and quantify erosive processes through Terrestrial Laser Scanning (TLS) and sediment trap measurements. While both methods effectively quantify sediment volumes, TLS proves more valuable for distinguishing processes and analysing slope morphological changes.

Over the three-year study period, 766 dm³ and 282 dm³ of soil were eroded from the south and north slopes respectively, resulting in annual erosion rates of 30000 Mg km⁻² year⁻¹ and 16500 Mg km⁻² year⁻¹. The erosion rates are relatively consistent with previous studies in these specific badlands, estimating erosion values ranging between 11000 Mg km⁻² year⁻¹ and 23000 Mg km⁻² year⁻¹. The findings reveal well-defined cyclic seasonal patterns: during autumn and winter, processes favouring the degradation of clay-rich slope material prevail, while in summer, soil detachment becomes predominant. Freeze-thaw cycles emerge as the most significant contributor to the degradation of clay-rich slope material, altering its internal structure and expanding its volume, swelling up to 5 cm in some areas. Conversely, during spring and summer, rainfall becomes the primary agent driving soil detachment and sediment transfer to sediment traps. Short-intense rainfalls, in particular, lead to rill and sheet erosion, identified as the primary erosive processes at the slope scale. Thus, this study highlights the critical roles of temperature and rainfall in the soil erosion process.

{"title":"Analysis of erosive processes and erosion rate by in-situ measurements and multi-temporal TLS surveys in a mountainous badland area, Vallcebre (Spain)","authors":"Ona Torra , Càrol Puig-Polo , Marcel Hürlimann , Jérôme Latron","doi":"10.1016/j.catena.2024.108622","DOIUrl":"10.1016/j.catena.2024.108622","url":null,"abstract":"<div><div>Badlands are highly erosive landforms characterized by dissected morphology, prevalent in regions with soft rocks and unconsolidated sediments, and are unsuitable for agriculture. Despite extensive research, understanding the dynamics of badlands remains limited, particularly in mountainous areas affected by freeze–thaw processes. This study aims to bridge this gap through a three-year investigation (November 2020 to November 2023), employing advanced geomatic techniques and a conventional approach. Focusing on two 8 m<sup>2</sup> and 12.5 m<sup>2</sup> badlands slopes facing north and south in the Upper Llobregat River Basin (Spain), the research aims to identify, characterize, and quantify erosive processes through Terrestrial Laser Scanning (TLS) and sediment trap measurements. While both methods effectively quantify sediment volumes, TLS proves more valuable for distinguishing processes and analysing slope morphological changes.</div><div>Over the three-year study period, 766 dm<sup>3</sup> and 282 dm<sup>3</sup> of soil were eroded from the south and north slopes respectively, resulting in annual erosion rates of 30000 Mg km<sup>−2</sup> year<sup>−1</sup> and 16500 Mg km<sup>−2</sup> year<sup>−1</sup>. The erosion rates are relatively consistent with previous studies in these specific badlands, estimating erosion values ranging between 11000 Mg km<sup>−2</sup> year<sup>−1</sup> and 23000 Mg km<sup>−2</sup> year<sup>−1</sup>. The findings reveal well-defined cyclic seasonal patterns: during autumn and winter, processes favouring the degradation of clay-rich slope material prevail, while in summer, soil detachment becomes predominant. Freeze-thaw cycles emerge as the most significant contributor to the degradation of clay-rich slope material, altering its internal structure and expanding its volume, swelling up to 5 cm in some areas. Conversely, during spring and summer, rainfall becomes the primary agent driving soil detachment and sediment transfer to sediment traps. Short-intense rainfalls, in particular, lead to rill and sheet erosion, identified as the primary erosive processes at the slope scale. Thus, this study highlights the critical roles of temperature and rainfall in the soil erosion process.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108622"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The response of soil microbial necromass carbon to global change: A global meta-analysis

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108693

Wenao Wu , Jiguang Feng , Xudong Wang , Jiatian Xiao , Wenkuan Qin , Biao Zhu

Soil organic carbon (SOC) is the largest carbon pool of terrestrial ecosystems and it is vulnerable to global change. As an important component of SOC, soil microbial necromass carbon (MNC) largely determines the dynamics of SOC. However, the response of MNC to global change on a global scale is not well understood. Here, we conducted a meta-analysis to assess the global response of MNC to warming, altered precipitation, nutrient addition, and elevated CO₂. Our results indicated that MNC was resistant to most global change factors. However, decreased precipitation reduced MNC by 6.79 % and fungal necromass carbon (FNC) by 8.99 %. In contrast, N addition had a favorable effect on MNC (+8.60 %), FNC (+7.61 %), and bacterial necromass carbon (BNC, +12.12 %). Additionally, initial environmental and experimental conditions affected the response of MNC to N addition. Notably, we found that MNC was more responsive in topsoil than in subsoil, which could account for the depth-dependent response of SOC. Furthermore, we found that the response of soil total nitrogen content and that of microbial biomass carbon mediated the MNC response to N addition. Overall, this study enhances our understanding of how MNC responds to global change on a global scale. In future studies, the response of MNC to global change in tropical/boreal regions, in long-term experiments, and in subsoils needs more attention.

{"title":"The response of soil microbial necromass carbon to global change: A global meta-analysis","authors":"Wenao Wu , Jiguang Feng , Xudong Wang , Jiatian Xiao , Wenkuan Qin , Biao Zhu","doi":"10.1016/j.catena.2024.108693","DOIUrl":"10.1016/j.catena.2024.108693","url":null,"abstract":"<div><div>Soil organic carbon (SOC) is the largest carbon pool of terrestrial ecosystems and it is vulnerable to global change. As an important component of SOC, soil microbial necromass carbon (MNC) largely determines the dynamics of SOC. However, the response of MNC to global change on a global scale is not well understood. Here, we conducted a meta-analysis to assess the global response of MNC to warming, altered precipitation, nutrient addition, and elevated CO<sub>2</sub>. Our results indicated that MNC was resistant to most global change factors. However, decreased precipitation reduced MNC by 6.79 % and fungal necromass carbon (FNC) by 8.99 %. In contrast, N addition had a favorable effect on MNC (+8.60 %), FNC (+7.61 %), and bacterial necromass carbon (BNC, +12.12 %). Additionally, initial environmental and experimental conditions affected the response of MNC to N addition. Notably, we found that MNC was more responsive in topsoil than in subsoil, which could account for the depth-dependent response of SOC. Furthermore, we found that the response of soil total nitrogen content and that of microbial biomass carbon mediated the MNC response to N addition. Overall, this study enhances our understanding of how MNC responds to global change on a global scale. In future studies, the response of MNC to global change in tropical/boreal regions, in long-term experiments, and in subsoils needs more attention.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108693"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Elevational patterns in the diversity and composition of soil archaeal and bacterial communities depend on climate, vegetation, and soil properties in an arid mountain ecosystem

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108679

Zhihao Zhang , Yan Lu , Li Li , Fanjiang Zeng , Xiangyi Li , Lei Li , Jian Yue

The continuous changes in climate, vegetation, and soil properties along elevational gradients provide a space-for-time method for probing the mechanisms behind the generation and maintenance of biodiversity. However, elevational patterns of soil microbial communities along elevational gradients and their driving mechanisms in arid mountain are poorly understood. The metagenomics technique was employed to examine the α-diversity and community composition of soil archaea and bacteria along elevational gradients ranging from 1707 to 3548 m in Mt. Middle Kunlun, China. The number of bacterial sequences was significantly higher than that of archaeal sequences, and the dominant phyla and genera in both communities showed significant differences in abundance across elevations. The α-diversity (Shannon index) displayed a monotonically increasing pattern for bacteria and a hump-shaped pattern for archaea, while the community composition of both archaea and bacteria demonstrated a similar hump-shaped trend. The community composition of archaea and bacteria were influenced by elevation via precipitation, vegetation, and soil properties. However, the underlying factors for these two microbial communities were different. Environmental-physiological constraints (e.g., soil water content and pH) were determined to be the main drivers of archaeal community composition. Bacterial community composition was primarily influenced by vegetation factors (such as plant diversity and cover) and soil nutrients (such as available nitrogen). This research offers a thorough examination of the biogeography of soil microbes in precipitation-sensitive or arid mountain ecosystems.

气候、植被和土壤特性沿海拔梯度的连续变化为探究生物多样性的产生和维持机制提供了一种以时间换空间的方法。然而，人们对干旱山区土壤微生物群落沿海拔梯度变化的模式及其驱动机制知之甚少。本研究采用元基因组学技术研究了中国中昆仑山海拔1707米至3548米梯度土壤古细菌和细菌的α多样性和群落组成。细菌序列的数量明显高于古细菌序列，两种群落中的优势菌门和优势菌属在不同海拔高度的丰度差异显著。细菌的α-多样性（香农指数）呈单调递增模式，而古细菌的α-多样性呈驼峰形模式，古细菌和细菌的群落组成也呈类似的驼峰形趋势。古细菌和细菌的群落组成受到海拔高度、降水、植被和土壤特性的影响。然而，这两种微生物群落的基本因素是不同的。环境生理制约因素（如土壤含水量和 pH 值）被认为是古细菌群落组成的主要驱动因素。细菌群落组成主要受植被因素（如植物多样性和覆盖度）和土壤养分（如可用氮）的影响。这项研究对降水敏感或干旱山区生态系统中土壤微生物的生物地理学进行了深入研究。

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引用次数: 0

Multi-proxy paleolimnological evidence for recent environmental degradation of Xingkai Lake, the largest shallow lake in Northeast Asia

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108625

Liangfang Li , Xuhui Dong , Zijian Xie , Yupei Zhang , Chunhua Li , Helen Bennion

Located at the border between China and Russia, Xingkai Lake is the largest shallow lake in Northeast Asia. Current studies based on the lake’s sediments mostly focus on the climatic evolution over the past 10³-10⁶ years, with limited research on high-resolution recent environmental changes. In this study, three short sediment cores were collected from the northern area (in the Chinese part) of the lake and dated using ²¹⁰Pb/¹³⁷Cs radiometric methods. The changes in diatom communities and sediment physicochemical indicators, such as total organic carbon (TOC), Pb, Fe/Mn, frequency-dependent magnetic susceptibility (χ_fd) and sediment accumulation rate (SAR), were analyzed to reconstruct environmental change in the northern part of Xingkai Lake over the last 200 years. Results show that the diatom assemblages were dominated by Aulacoseira granulata prior to the 1990s. Since the late 1990s, eutrophication has emerged, with a shift to Cyclostephanos dubius as the dominant diatom species. Cultivated land area, χ_fd, sediment TP and annual mean wind speed were the four most important environmental variables explaining the shifts in the diatom assemblages, suggesting that agricultural disturbance is the main driver of environmental degradation. Additionally, the study reveals some spatial difference in depositional environments in the lake. The relative stability of the diatom assemblages before the late 1990s suggests that Xingkai Lake experienced low levels of eutrophication prior to the start of the twenty-first century and may thus have a higher ecosystem resilience than is typically seen in smaller lakes. The mean epilimnetic TP concentration of 35 μg/L measured before the significant diatom change can be used as a reference nutrient condition for eutrophication management of this lake. The study provides a scientific basis for the management of Xingkai Lake in China and Russia, and also enriches the research cases of environmental change in the world’s large lakes.

兴凯湖位于中俄边境，是东北亚最大的浅水湖泊。目前基于该湖沉积物的研究大多集中于过去 103-106 年的气候演变，而对高分辨率的近期环境变化研究有限。本研究从湖泊北部地区（中国部分）采集了三个短沉积物岩芯，并采用 210Pb/137Cs 放射性方法测定了其年代。通过分析硅藻群落和沉积物理化指标，如总有机碳（TOC）、铅、铁/锰、频率相关磁感应强度（χfd）和沉积物堆积率（SAR）的变化，重建兴凯湖北部近 200 年的环境变化。结果表明，20 世纪 90 年代以前，硅藻群以颗粒硅藻（Aulacoseira granulata）为主。自 20 世纪 90 年代末以来，出现了富营养化现象，硅藻的优势种转变为 Cyclostephanos dubius。耕地面积、χfd、沉积物 TP 和年平均风速是解释硅藻群变化的四个最重要的环境变量，这表明农业干扰是环境退化的主要驱动因素。此外，研究还揭示了湖泊沉积环境的空间差异。20 世纪 90 年代末之前硅藻群的相对稳定性表明，兴凯湖在 21 世纪初之前经历了较低程度的富营养化，因此其生态系统的恢复能力可能高于一般的小型湖泊。在硅藻发生显著变化之前测得的平均上浮 TP 浓度为 35 μg/L，可作为该湖泊富营养化管理的参考营养条件。该研究为中国和俄罗斯的兴凯湖治理提供了科学依据，同时也丰富了世界大型湖泊环境变化的研究案例。

{"title":"Multi-proxy paleolimnological evidence for recent environmental degradation of Xingkai Lake, the largest shallow lake in Northeast Asia","authors":"Liangfang Li , Xuhui Dong , Zijian Xie , Yupei Zhang , Chunhua Li , Helen Bennion","doi":"10.1016/j.catena.2024.108625","DOIUrl":"10.1016/j.catena.2024.108625","url":null,"abstract":"<div><div>Located at the border between China and Russia, Xingkai Lake is the largest shallow lake in Northeast Asia. Current studies based on the lake’s sediments mostly focus on the climatic evolution over the past 10<sup>3</sup>-10<sup>6</sup> years, with limited research on high-resolution recent environmental changes. In this study, three short sediment cores were collected from the northern area (in the Chinese part) of the lake and dated using <sup>210</sup>Pb/<sup>137</sup>Cs radiometric methods. The changes in diatom communities and sediment physicochemical indicators, such as total organic carbon (TOC), Pb, Fe/Mn, frequency-dependent magnetic susceptibility (χ<sub>fd</sub>) and sediment accumulation rate (SAR), were analyzed to reconstruct environmental change in the northern part of Xingkai Lake over the last 200 years. Results show that the diatom assemblages were dominated by <em>Aulacoseira granulata</em> prior to the 1990s. Since the late 1990s, eutrophication has emerged, with a shift to <em>Cyclostephanos dubius</em> as the dominant diatom species. Cultivated land area, χ<sub>fd</sub>, sediment TP and annual mean wind speed were the four most important environmental variables explaining the shifts in the diatom assemblages, suggesting that agricultural disturbance is the main driver of environmental degradation. Additionally, the study reveals some spatial difference in depositional environments in the lake. The relative stability of the diatom assemblages before the late 1990s suggests that Xingkai Lake experienced low levels of eutrophication prior to the start of the twenty-first century and may thus have a higher ecosystem resilience than is typically seen in smaller lakes. The mean epilimnetic TP concentration of 35 μg/L measured before the significant diatom change can be used as a reference nutrient condition for eutrophication management of this lake. The study provides a scientific basis for the management of Xingkai Lake in China and Russia, and also enriches the research cases of environmental change in the world’s large lakes.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108625"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanisms of hydraulic erosion control in different microrelief patterns of loess sloped farmland under continuous rainfall 连续降雨条件下黄土坡农田不同微地形的水力侵蚀控制机制

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108630

Xinkai Zhao , Xiaoyu Song , Danyang Wang , Lanjun Li , Pengfei Meng , Chong Fu , Long Wang , Wanyin Wei , Yu Liu , Huaiyou Li

Different microrelief patterns of sloped farmland have important effects on soil erosion. However, its hydraulic erosion control mechanism under continuous rainfall is unclear. In this study, the effects of two microrelief patterns (reservoir tillage (RT) and contour tillage (CT)) of sloped farmland on runoff, soil erosion, and hydrodynamic parameters were investigated at the plot scale using simulated rainfall and high-definition photography methods. Smooth slopes (SS) were chosen as a control. The test rainfall intensities (RIs) were selected as 30, 60, 90, and 120 mm h⁻¹. Two continuous rainfall events, each lasting 40 min, were conducted on each type of slope. The results show that the different microrelief patterns have a twofold role in soil erosion on slopes as influenced by rainfall conditions. During the first rainfall, compared to SS, the RT and CT increased the Darcy–Weisbach coefficient and reduced the surface flow velocity. The RT and CT significantly increased the initial runoff time and reduced runoff yield (10.9–69.46 %) and sediment yield (9.87–74.87 %). However, during the second rainfall event, the water-retaining terrain of the RT and CT was destroyed. This resulted in reduced Darcy–Weisbach coefficients and increased flow velocities on the RT and CT. Compared to the SS, the RT reduced the runoff yield (10.59–63.86 %) and sediment yield (19.04–51.17 %) under RIs of 30, 60, and 90mm h⁻¹, but the magnitude of reduction decreased compared to the first rainfall event. The RT increased the runoff yield (11.32 %) and sediment yield (6.08 %) under the RI of 120 mm h⁻¹. The CT increased the runoff yield (19.13–24.88 %) and sediment yield (15.75–46.32 %) under all four RIs. In addition, statistical analysis indicated that stream power could explain 79 % of the changes in runoff and sediment yield on RT and CT, and effective stream power could account for 79 % of the variations in runoff and sediment yield on SS. Stream power served as the optimal indicator for characterizing the runoff and sediment yield rates on RT and CT, whereas effective stream power was the best metric for SS. This study can help us to better explain the mechanism of hydraulic erosion control in different microrelief patterns.

{"title":"Mechanisms of hydraulic erosion control in different microrelief patterns of loess sloped farmland under continuous rainfall","authors":"Xinkai Zhao , Xiaoyu Song , Danyang Wang , Lanjun Li , Pengfei Meng , Chong Fu , Long Wang , Wanyin Wei , Yu Liu , Huaiyou Li","doi":"10.1016/j.catena.2024.108630","DOIUrl":"10.1016/j.catena.2024.108630","url":null,"abstract":"<div><div>Different microrelief patterns of sloped farmland have important effects on soil erosion. However, its hydraulic erosion control mechanism under continuous rainfall is unclear. In this study, the effects of two microrelief patterns (reservoir tillage (RT) and contour tillage (CT)) of sloped farmland on runoff, soil erosion, and hydrodynamic parameters were investigated at the plot scale using simulated rainfall and high-definition photography methods. Smooth slopes (SS) were chosen as a control. The test rainfall intensities (<em>RI</em>s) were selected as 30, 60, 90, and 120 mm h<sup>−1</sup>. Two continuous rainfall events, each lasting 40 min, were conducted on each type of slope. The results show that the different microrelief patterns have a twofold role in soil erosion on slopes as influenced by rainfall conditions. During the first rainfall, compared to SS, the RT and CT increased the Darcy–Weisbach coefficient and reduced the surface flow velocity. The RT and CT significantly increased the initial runoff time and reduced runoff yield (10.9–69.46 %) and sediment yield (9.87–74.87 %). However, during the second rainfall event, the water-retaining terrain of the RT and CT was destroyed. This resulted in reduced Darcy–Weisbach coefficients and increased flow velocities on the RT and CT. Compared to the SS, the RT reduced the runoff yield (10.59–63.86 %) and sediment yield (19.04–51.17 %) under <em>RI</em>s of 30, 60, and 90mm h<sup>−1</sup>, but the magnitude of reduction decreased compared to the first rainfall event. The RT increased the runoff yield (11.32 %) and sediment yield (6.08 %) under the <em>RI</em> of 120 mm h<sup>−1</sup>. The CT increased the runoff yield (19.13–24.88 %) and sediment yield (15.75–46.32 %) under all four <em>RI</em>s. In addition, statistical analysis indicated that stream power could explain 79 % of the changes in runoff and sediment yield on RT and CT, and effective stream power could account for 79 % of the variations in runoff and sediment yield on SS. Stream power served as the optimal indicator for characterizing the runoff and sediment yield rates on RT and CT, whereas effective stream power was the best metric for SS. This study can help us to better explain the mechanism of hydraulic erosion control in different microrelief patterns.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108630"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143182404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Uncovering soil preferential flow induced by different drip irrigation emitter settings: Insights integrating wetting-fronts image variability, HYDRUS-2D, and active region model

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108669

Rui Chen , Vilim Filipović , Jinzhu Zhang , Wenhao Li , Hanchun Ye , Jihong Zhang , Zhenhua Wang

Drip irrigation has gained widespread adoption in arid regions globally to counteract the water scarcity, yet the non-uniformity of soil water flow under drip irrigation remains inadequately understood. This study presented an indoor infiltration experiment with two soil types (sandy loam and sandy), three emitter sapcing (10 cm, 20 cm, and 30 cm), and two discharge rates (3 L/h and 4 L/h). We analyzed wetting front image variability, using HYDRUS-2D to interpret fractal parameters in active region model during infiltration. Initially, the wetting front was unstable, with a preferential flow ratio dropping from 90 % to 20 % and a variation coefficient decreasing from approximately 2 to below 1 across both soil types. The preferential pathways were found forming in a finger shape ways. Fractal parameters peaked at 15–30 min in sandy loam and 5–10 min in sandy soils, reflecting this instability. HYDRUS-2D data confirmed the non-uniformity indicated by the active region model, showing reduced fractal parameters with wider emitter spacing in sandy soils and an increase with larger spacing in sandy loam. Moreover, the principal component analysis identified optimal irrigation parameters: a 20 cm spacing with a 4 L/h discharge for sandy loam and a 40 cm spacing with the same discharge for sandy soils. Our research confirmed the presence of soil preferential flow even under drip irrigation and developed a new evaluation framework to assess the effectiveness of various drip irrigation parameters, considering soil preferential flow. This research offers new insights into optimizing drip irrigation in arid regions, enhancing water management in these areas.

{"title":"Uncovering soil preferential flow induced by different drip irrigation emitter settings: Insights integrating wetting-fronts image variability, HYDRUS-2D, and active region model","authors":"Rui Chen , Vilim Filipović , Jinzhu Zhang , Wenhao Li , Hanchun Ye , Jihong Zhang , Zhenhua Wang","doi":"10.1016/j.catena.2024.108669","DOIUrl":"10.1016/j.catena.2024.108669","url":null,"abstract":"<div><div>Drip irrigation has gained widespread adoption in arid regions globally to counteract the water scarcity, yet the non-uniformity of soil water flow under drip irrigation remains inadequately understood. This study presented an indoor infiltration experiment with two soil types (sandy loam and sandy), three emitter sapcing (10 cm, 20 cm, and 30 cm), and two discharge rates (3 L/h and 4 L/h). We analyzed wetting front image variability, using HYDRUS-2D to interpret fractal parameters in active region model during infiltration. Initially, the wetting front was unstable, with a preferential flow ratio dropping from 90 % to 20 % and a variation coefficient decreasing from approximately 2 to below 1 across both soil types. The preferential pathways were found forming in a finger shape ways. Fractal parameters peaked at 15–30 min in sandy loam and 5–10 min in sandy soils, reflecting this instability. HYDRUS-2D data confirmed the non-uniformity indicated by the active region model, showing reduced fractal parameters with wider emitter spacing in sandy soils and an increase with larger spacing in sandy loam. Moreover, the principal component analysis identified optimal irrigation parameters: a 20 cm spacing with a 4 L/h discharge for sandy loam and a 40 cm spacing with the same discharge for sandy soils. Our research confirmed the presence of soil preferential flow even under drip irrigation and developed a new evaluation framework to assess the effectiveness of various drip irrigation parameters, considering soil preferential flow. This research offers new insights into optimizing drip irrigation in arid regions, enhancing water management in these areas.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108669"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143180644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Landslide susceptibility prediction in the loess tableland considering geomorphic evolution

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108668

Xiaokang Liu , Shuai Shao , Chen Zhang , Shengjun Shao

To explore the relationship between the loess tableland geomorphic evolution and landslide susceptibility, a loess tableland area in the northern of Xi’an City was selected in this study. The study area was divided into four areas according to the type of loess tableland. A complete historical landslide inventory was created and 11 landslide factors were selected. Landslide susceptibility prediction was performed for the subarea and the whole area based on the SVM and RF models, respectively, and several landslide susceptibility maps were generated. The results show that the prediction of landslide susceptibility in loess tableland areas needs to take into account the influence of its landscape evolution, and more accurate results can be obtained by calculating individually for different sub-areas. The RF model has strong performance in landslide susceptibility prediction when considering the tableland evolution, while the SVM model is better when considering the whole region as a whole. Multiple factors, such as human activities and river erosion, have increased the landslide susceptibility of the residual tableland phase, and repeated landslides along the tableland margins have led to a continuous reduction of the loess tableland surface. Given the importance of tableland landforms in the Loess Plateau region, a framework for susceptibility mapping and zonation was proposed, which is suitable for loess tableland regions where multiple developmental phases co-exist. This study strengthens the understanding of landslide development and susceptibility in response to the landscape evolution of the loess tableland and provides support for disaster prevention and mitigation and land planning.

{"title":"Landslide susceptibility prediction in the loess tableland considering geomorphic evolution","authors":"Xiaokang Liu , Shuai Shao , Chen Zhang , Shengjun Shao","doi":"10.1016/j.catena.2024.108668","DOIUrl":"10.1016/j.catena.2024.108668","url":null,"abstract":"<div><div>To explore the relationship between the loess tableland geomorphic evolution and landslide susceptibility, a loess tableland area in the northern of Xi’an City was selected in this study. The study area was divided into four areas according to the type of loess tableland. A complete historical landslide inventory was created and 11 landslide factors were selected. Landslide susceptibility prediction was performed for the subarea and the whole area based on the SVM and RF models, respectively, and several landslide susceptibility maps were generated. The results show that the prediction of landslide susceptibility in loess tableland areas needs to take into account the influence of its landscape evolution, and more accurate results can be obtained by calculating individually for different sub-areas. The RF model has strong performance in landslide susceptibility prediction when considering the tableland evolution, while the SVM model is better when considering the whole region as a whole. Multiple factors, such as human activities and river erosion, have increased the landslide susceptibility of the residual tableland phase, and repeated landslides along the tableland margins have led to a continuous reduction of the loess tableland surface. Given the importance of tableland landforms in the Loess Plateau region, a framework for susceptibility mapping and zonation was proposed, which is suitable for loess tableland regions where multiple developmental phases co-exist. This study strengthens the understanding of landslide development and susceptibility in response to the landscape evolution of the loess tableland and provides support for disaster prevention and mitigation and land planning.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108668"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143180648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing the soil moisture-vegetation mutual feedback relationship in different climatic regions of mainland China

IF 5.4 1区农林科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY

Catena

Pub Date : 2025-02-01 DOI: 10.1016/j.catena.2024.108684

Zhaoqiang Zhou , Ping Xue , Xin Zhou , Tian Wang , Yibo Ding , Yiyang Zhao , Peng Chen , Xiaowen Wang

Exploring the mutual feedback relationship between vegetation and soil moisture (SM) is highly important for water resource management, soil and water conservation and terrestrial carbon sinks under changing environment. However, the mutual feedback relationship between vegetation and SM is not fully understood. To this end, this study firstly introduced convergent cross mapping (CCM) to evaluate the feedback relationship between NDVI and SM in in different climatic regions of China. The spatial trend coupling relationship was also analyzed. The results indicated that (1) NDVI was positively with SM in most areas of China, while the proportions of negatively correlated and uncorrelated areas increase with depth. (2) The causality is different for different depth. NDVI and SM1/SM2/SM3 were mutual feedback in most areas of China (65.52%/70.41%/76.4%). In areas with poor correlation results, CCM can better explain the relationship between SM and NDVI. (3) The coupling relationship between SM and NDVI is primarily divided into the co-increasing area of the northeastern Qinghai-Tibet Plateau, the vegetation greening-SM decreasing area in Central China, and the mixed area in Northeast China. The research results have important reference significance for ecological engineering management, the sustainable use of land and water resources, and carbon sequestration.

{"title":"Assessing the soil moisture-vegetation mutual feedback relationship in different climatic regions of mainland China","authors":"Zhaoqiang Zhou , Ping Xue , Xin Zhou , Tian Wang , Yibo Ding , Yiyang Zhao , Peng Chen , Xiaowen Wang","doi":"10.1016/j.catena.2024.108684","DOIUrl":"10.1016/j.catena.2024.108684","url":null,"abstract":"<div><div>Exploring the mutual feedback relationship between vegetation and soil moisture (SM) is highly important for water resource management, soil and water conservation and terrestrial carbon sinks under changing environment. However, the mutual feedback relationship between vegetation and SM is not fully understood. To this end, this study firstly introduced convergent cross mapping (CCM) to evaluate the feedback relationship between NDVI and SM in in different climatic regions of China. The spatial trend coupling relationship was also analyzed. The results indicated that (1) NDVI was positively with SM in most areas of China, while the proportions of negatively correlated and uncorrelated areas increase with depth. (2) The causality is different for different depth. NDVI and SM1/SM2/SM3 were mutual feedback in most areas of China (65.52%/70.41%/76.4%). In areas with poor correlation results, CCM can better explain the relationship between SM and NDVI. (3) The coupling relationship between SM and NDVI is primarily divided into the co-increasing area of the northeastern Qinghai-Tibet Plateau, the vegetation greening-SM decreasing area in Central China, and the mixed area in Northeast China. The research results have important reference significance for ecological engineering management, the sustainable use of land and water resources, and carbon sequestration.</div></div>","PeriodicalId":9801,"journal":{"name":"Catena","volume":"249 ","pages":"Article 108684"},"PeriodicalIF":5.4,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0