The conflict between economic development and ecological protection in land use (LU) has been a significant and widely discussed topic. The city circle concept has been proposed to promote economic growth through its strong agglomeration effect. It contains the core city and its surrounding area, and economic activities and ecosystems are highly intertwined within this geographic unit. Meanwhile, population, industry, and infrastructure are often concentrated within the urban sphere, which results in a concentrated demand for land, water, and ecosystem services. As a result, LU conflicts are more pronounced in urban areas. Here, we used gross domestic product (GDP) and gross ecosystem product (GEP) to reflect economic and ecological levels, then linked LU change into the coupling relationship between GDP and GEP of the Wuhan City Circle (WHCC), China, to analyze the economic and ecological developments of WHCC. Finally, we constructed a partial least squares structural equation modeling to explore the key drivers affecting the coupling of real GDP and GEP. Our results revealed significant LU changes between 1990 and 2020 for the WHCC. Paddy fields, dry lands, and some forestlands decreased, while built-up lands and water areas both increased. Real GDP of the WHCC increased from $1.04 × 106 in 1990 to $3.04 × 107 in 2020. While the GEP of the WHCC increased during 1990–2010 and decreased during 2010–2020. Additionally, GEP exhibited a significant spatial heterogeneity, with high GEP concentrated in the central and southeastern regions. Moreover, we constructed a conceptual model for coupling real GDP and GEP, then used structural equation modeling to reveal their relationship. Real GDP had a positive effect on GEP. Furthermore, the proportion of construction land and ecological land as intermediate variables played an important direct and indirect role in real GDP and GEP. Consequently, landscape planning was proposed to enhance the green infrastructure of the WHCC. Our findings provide a reference and experience on land resource allocation for maintaining sustainable development in the city circle.
土地利用（LU）中经济发展与生态保护之间的矛盾一直是一个重要且被广泛讨论的话题。城市圈概念的提出是为了通过其强大的集聚效应促进经济增长。它包含核心城市及其周边地区，在这一地理单元内，经济活动与生态系统高度交织。同时，人口、工业和基础设施通常都集中在城市范围内，这导致了对土地、水和生态系统服务的集中需求。因此，LU 冲突在城市地区更为突出。在此，我们使用国内生产总值（GDP）和生态系统生产总值（GEP）来反映经济和生态水平，然后将土地利用变化与中国武汉城市圈（WHCC）GDP 和 GEP 的耦合关系联系起来，分析武汉城市圈的经济和生态发展。最后，我们构建了偏最小二乘法结构方程模型，以探讨影响实际 GDP 与 GEP 耦合关系的关键驱动因素。我们的研究结果表明，从 1990 年到 2020 年，西海固地区的土地利用发生了重大变化。水田、旱地和部分林地减少，而建筑用地和水域面积均增加。西高地的实际 GDP 从 1990 年的 1.04 × 106 美元增至 2020 年的 3.04 × 107 美元。1990-2010年间，西高止湖中心的GEP有所增加，而2010-2020年间则有所减少。此外，GEP 表现出明显的空间异质性，高 GEP 集中在中部和东南部地区。此外，我们还构建了一个将实际 GDP 与 GEP 相结合的概念模型，并利用结构方程模型揭示了两者之间的关系。实际 GDP 对 GEP 有正向影响。此外，建设用地和生态用地的比例作为中间变量，对实际 GDP 和 GEP 起着重要的直接和间接作用。因此，建议通过景观规划来加强西隧的绿色基础设施。我们的研究结果为维持城市圈可持续发展的土地资源配置提供了参考和经验。
{"title":"Impacts of Urbanization on Economic Development and Ecological Protection of the Wuhan City Circle, China","authors":"Yiting Li, Chunbo Huang, Shuangshuang Liu, Jing Cheng, Yang Xiang, Changhui Peng","doi":"10.1002/ldr.5298","DOIUrl":"https://doi.org/10.1002/ldr.5298","url":null,"abstract":"The conflict between economic development and ecological protection in land use (LU) has been a significant and widely discussed topic. The city circle concept has been proposed to promote economic growth through its strong agglomeration effect. It contains the core city and its surrounding area, and economic activities and ecosystems are highly intertwined within this geographic unit. Meanwhile, population, industry, and infrastructure are often concentrated within the urban sphere, which results in a concentrated demand for land, water, and ecosystem services. As a result, LU conflicts are more pronounced in urban areas. Here, we used gross domestic product (GDP) and gross ecosystem product (GEP) to reflect economic and ecological levels, then linked LU change into the coupling relationship between GDP and GEP of the Wuhan City Circle (WHCC), China, to analyze the economic and ecological developments of WHCC. Finally, we constructed a partial least squares structural equation modeling to explore the key drivers affecting the coupling of real GDP and GEP. Our results revealed significant LU changes between 1990 and 2020 for the WHCC. Paddy fields, dry lands, and some forestlands decreased, while built-up lands and water areas both increased. Real GDP of the WHCC increased from $1.04 × 10<sup>6</sup> in 1990 to $3.04 × 10<sup>7</sup> in 2020. While the GEP of the WHCC increased during 1990–2010 and decreased during 2010–2020. Additionally, GEP exhibited a significant spatial heterogeneity, with high GEP concentrated in the central and southeastern regions. Moreover, we constructed a conceptual model for coupling real GDP and GEP, then used structural equation modeling to reveal their relationship. Real GDP had a positive effect on GEP. Furthermore, the proportion of construction land and ecological land as intermediate variables played an important direct and indirect role in real GDP and GEP. Consequently, landscape planning was proposed to enhance the green infrastructure of the WHCC. Our findings provide a reference and experience on land resource allocation for maintaining sustainable development in the city circle.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soil nutrients are crucial to assess land reclamation quality, and the use of various types of remote sensing data for soil nutrient inversion has been a key focus for soil monitoring. However, fewer studies have been conducted using satellite-based hyperspectral remote sensing. To explore the potential of satellite-based hyperspectral remote sensing in soil nutrient monitoring, this study selected soil organic matter, total nitrogen, available phosphorus, and available potassium content data from 83 sample sites using ZhuHai-1 hyperspectral data. After spectral transformation and feature extraction, various inversion models were constructed, including partial least squares regression, support vector machine, recurrent neural network, and random forest. After verification by accuracy, the best spectral-model combination was used for inversion. The results showed that the R-squared range of the inversion models was 0.67748–0.78115. High content areas of soil organic matter and available potassium exhibited concentrated and contiguous features, while high content areas of total nitrogen and available phosphorus were more fragmented and fine-grained. Alfalfa grassland plays a vital role in improving reconstructed soil in the early reclamation stage, and agricultural activities have differential impacts on soil nutrient accumulation. This study provides a theoretical basis for verifying the application capability of ZhuHai-1 hyperspectral satellite data in soil monitoring.
土壤养分对评估土地复垦质量至关重要，利用各类遥感数据进行土壤养分反演一直是土壤监测的重点。然而，利用卫星高光谱遥感技术开展的研究较少。为探索卫星高光谱遥感在土壤养分监测中的应用潜力，本研究利用珠海一号高光谱数据选取了 83 个样点的土壤有机质、全氮、可利用磷和可利用钾含量数据。经过光谱变换和特征提取，构建了多种反演模型，包括偏最小二乘回归、支持向量机、递归神经网络和随机森林。经过精度验证后，采用最佳光谱-模型组合进行反演。结果表明，反演模型的 R 平方范围为 0.67748-0.78115。土壤有机质和可利用钾的高含量区表现出集中和连片的特征，而全氮和可利用磷的高含量区则更加破碎和细粒化。紫花苜蓿草地在复垦初期对改良重建土壤起着重要作用，而农业活动对土壤养分积累有不同的影响。该研究为验证 "珠海一号 "高光谱卫星数据在土壤监测中的应用能力提供了理论依据。
{"title":"Soil Nutrients Inversion in Open-Pit Coal Mine Reclamation Area of Loess Plateau, China: A Study Based on ZhuHai-1 Hyperspectral Remote Sensing","authors":"Hongyu Wang, Juan Wang, Rongrong Ma, Wei Zhou","doi":"10.1002/ldr.5291","DOIUrl":"https://doi.org/10.1002/ldr.5291","url":null,"abstract":"Soil nutrients are crucial to assess land reclamation quality, and the use of various types of remote sensing data for soil nutrient inversion has been a key focus for soil monitoring. However, fewer studies have been conducted using satellite-based hyperspectral remote sensing. To explore the potential of satellite-based hyperspectral remote sensing in soil nutrient monitoring, this study selected soil organic matter, total nitrogen, available phosphorus, and available potassium content data from 83 sample sites using ZhuHai-1 hyperspectral data. After spectral transformation and feature extraction, various inversion models were constructed, including partial least squares regression, support vector machine, recurrent neural network, and random forest. After verification by accuracy, the best spectral-model combination was used for inversion. The results showed that the <i>R</i>-squared range of the inversion models was 0.67748–0.78115. High content areas of soil organic matter and available potassium exhibited concentrated and contiguous features, while high content areas of total nitrogen and available phosphorus were more fragmented and fine-grained. Alfalfa grassland plays a vital role in improving reconstructed soil in the early reclamation stage, and agricultural activities have differential impacts on soil nutrient accumulation. This study provides a theoretical basis for verifying the application capability of ZhuHai-1 hyperspectral satellite data in soil monitoring.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142330229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rare earth elements are crucial for applications in aerospace, electronics, petrochemicals, and metallurgical industries. However, as rare earth mining expands, their tailings accumulate, leading to severe soil erosion and threatening of the local ecology. This study aimed to investigate the impact of planting Paspalum wettsteinii and soil amendments, including superabsorbent polymers (SAPs), organics, minerals, and urea, in controlling soil erosion. Six treatments, each with four replicates, were implemented on micro‐runoff plots on rare earth tailings: (1) bare slopes, (2) bare slopes repaired with composite soil amendments, (3) grass slopes, (4) grass slopes repaired with SAPs, and grass slopes repaired with (5) low or (6) high amounts of composites. Over 11 months, natural rainfall patterns, vegetation coverage, runoff yield, and sediment yield were monitored on the tailings' slope. Initially, plant growth was slow on bare slopes (56% vegetation coverage at 130 days), but it significantly improved with soil amendments (74% vegetation coverage on grass slopes repaired with SAPs and 97% vegetation coverage on grass slopes repaired with composites at 52 days). Adding composites onto bare slopes marginally reduced runoff and sediment yields by 3% and 16%, respectively. Vegetation, especially when combined with composites, significantly reduced runoff by 77% and sediment by 96%, while supplementing planting with SAPs decreased runoff by 41% and sediment by 88%. Planting without any amendments resulted in lower reductions of 26% in runoff and 81% in sediment. The results of the structural equation model showed that SAPs and fertilizers indirectly reduce sediment yield by increasing vegetation cover, with fertilizers also exercising a positive direct effect on sediment regulation. Our findings highlight how SAPs coupled with organic and inorganic fertilizers promote plant growth and erosion control, as applying these composites alone is less effective in controlling erosion on bare slopes. These results have promising implications for the ecological restoration of rare earth tailings.
稀土元素对航空航天、电子、石化和冶金工业的应用至关重要。然而，随着稀土开采规模的扩大，其尾矿不断积累，导致了严重的水土流失，威胁着当地的生态环境。本研究旨在探讨种植覆盆子和土壤改良剂（包括超吸水聚合物 (SAP)、有机物、矿物质和尿素）对控制水土流失的影响。在稀土尾矿微径流地块上进行了六种处理，每种处理有四个重复：(1) 裸露斜坡；(2) 用复合土壤改良剂修复的裸坡；(3) 草坡；(4) 用 SAP 修复的草坡；以及用(5) 低量或(6) 高量复合材料修复的草坡。在 11 个月的时间里，对尾矿坡的自然降雨模式、植被覆盖率、径流量和沉积物产量进行了监测。最初，裸坡上的植物生长缓慢（130 天时植被覆盖率为 56%），但土壤改良后植被覆盖率明显提高（52 天时，用 SAP 修复的草坡植被覆盖率为 74%，用复合材料修复的草坡植被覆盖率为 97%）。在裸露斜坡上添加复合材料可使径流量和沉积物量分别减少 3% 和 16%。植被，尤其是与复合材料结合种植时，可显著减少 77% 的径流量和 96% 的泥沙量，而辅以 SAP 的种植可减少 41% 的径流量和 88% 的泥沙量。不添加任何添加剂的种植可减少 26% 的径流和 81% 的沉积物。结构方程模型的结果表明，SAP 和肥料通过增加植被覆盖率间接减少了泥沙产量，肥料还对泥沙调节产生了积极的直接影响。我们的研究结果突显了 SAP 与有机肥和无机肥的结合如何促进植物生长和控制侵蚀，因为在裸露的山坡上单独施用这些复合肥料对控制侵蚀的效果较差。这些结果对稀土尾矿的生态恢复具有重要意义。
{"title":"Controlling Soil Erosion of Tailings From Rare Earth Mines With Paspalum wettsteinii and Soil Amendments","authors":"Yanzi He, Zhiyuan Tian, Zhujun Gu, Bingxiao Wu, Yin Liang","doi":"10.1002/ldr.5313","DOIUrl":"https://doi.org/10.1002/ldr.5313","url":null,"abstract":"Rare earth elements are crucial for applications in aerospace, electronics, petrochemicals, and metallurgical industries. However, as rare earth mining expands, their tailings accumulate, leading to severe soil erosion and threatening of the local ecology. This study aimed to investigate the impact of planting <jats:italic>Paspalum wettsteinii</jats:italic> and soil amendments, including superabsorbent polymers (SAPs), organics, minerals, and urea, in controlling soil erosion. Six treatments, each with four replicates, were implemented on micro‐runoff plots on rare earth tailings: (1) bare slopes, (2) bare slopes repaired with composite soil amendments, (3) grass slopes, (4) grass slopes repaired with SAPs, and grass slopes repaired with (5) low or (6) high amounts of composites. Over 11 months, natural rainfall patterns, vegetation coverage, runoff yield, and sediment yield were monitored on the tailings' slope. Initially, plant growth was slow on bare slopes (56% vegetation coverage at 130 days), but it significantly improved with soil amendments (74% vegetation coverage on grass slopes repaired with SAPs and 97% vegetation coverage on grass slopes repaired with composites at 52 days). Adding composites onto bare slopes marginally reduced runoff and sediment yields by 3% and 16%, respectively. Vegetation, especially when combined with composites, significantly reduced runoff by 77% and sediment by 96%, while supplementing planting with SAPs decreased runoff by 41% and sediment by 88%. Planting without any amendments resulted in lower reductions of 26% in runoff and 81% in sediment. The results of the structural equation model showed that SAPs and fertilizers indirectly reduce sediment yield by increasing vegetation cover, with fertilizers also exercising a positive direct effect on sediment regulation. Our findings highlight how SAPs coupled with organic and inorganic fertilizers promote plant growth and erosion control, as applying these composites alone is less effective in controlling erosion on bare slopes. These results have promising implications for the ecological restoration of rare earth tailings.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yujie Zhu, Kang Hou, Yue Chang, Xuxiang Li, Kexin Yang
The spatial heterogeneity of ecological vulnerability (EV) is a key indicator of regional ecosystem differentiation. However, identifying the factors that contribute to this heterogeneity remains a challenge in current research. This study proposed the “Ecological vulnerability‐spatial heterogeneity‐zone” (ESHZ) framework as a solution to overcome the difficulties of monitoring spatial heterogeneity. Then, based on the typical river valley city Baoji in Northwest China as the research object, this framework was used to analyze and predict the evolution law of heterogeneity of EV from 2000 to 2030. The findings indicate the following: (1) Synthesized ecological vulnerability index (SEVI) in 2000 and 2020 was 2.47 and 2.49, respectively, with less than 5% of the total area transitioning to areas of higher EV, indicating a relatively stable ecological environment. (2) The clustering characteristics of EV remained stable, primarily showing non‐significant, high–high, and low–low clustering, with varying degrees of heterogeneity across different regions. (3) Factors analysis revealed that DEM and LUCC had been the dominant factors of EV, and that interactions between factors were stronger than interactions within them, suggesting that its spatial heterogeneity was the result of a combination of factors. (4) The CA‐Markov model predicted a gradual improvement in the ecological environment by 2030, with a Kappa coefficient test value of 0.7733. The framework constructed in this study proposes a perspective for improved analyses of spatial heterogeneity of ecosystems, providing a viable approach to the management of regional ecological vulnerability.
生态脆弱性（EV）的空间异质性是区域生态系统差异的一个关键指标。然而，确定造成这种异质性的因素仍然是当前研究中的一项挑战。本研究提出了 "生态脆弱性-空间异质性-区域"（ESHZ）框架，作为克服空间异质性监测困难的解决方案。然后，以中国西北典型的河谷城市宝鸡为研究对象，利用该框架分析和预测了 2000-2030 年电动汽车异质性的演变规律。研究结果表明(1）2000 年和 2020 年的综合生态脆弱指数（SEVI）分别为 2.47 和 2.49，只有不到 5%的总面积过渡到高 EV 区域，表明生态环境相对稳定。(2）EV 的聚类特征保持稳定，主要表现为不显著聚类、高-高聚类和低-低聚类，不同区域存在不同程度的异质性。(3）因子分析显示，DEM 和 LUCC 一直是 EV 的主导因子，且因子间的相互作用强于因子内的相互作用，表明 EV 的空间异质性是多种因子综合作用的结果。(4) CA-Markov 模型预测到 2030 年生态环境将逐步改善，Kappa 系数检验值为 0.7733。本研究构建的框架为改进生态系统空间异质性分析提出了一个视角，为区域生态脆弱性管理提供了一种可行的方法。
{"title":"Analysis of Ecological Vulnerability Control Strategies for Typical River Valley Cities in Northwest China: A Perspective of Spatial Heterogeneity","authors":"Yujie Zhu, Kang Hou, Yue Chang, Xuxiang Li, Kexin Yang","doi":"10.1002/ldr.5320","DOIUrl":"https://doi.org/10.1002/ldr.5320","url":null,"abstract":"The spatial heterogeneity of ecological vulnerability (EV) is a key indicator of regional ecosystem differentiation. However, identifying the factors that contribute to this heterogeneity remains a challenge in current research. This study proposed the “Ecological vulnerability‐spatial heterogeneity‐zone” (ESHZ) framework as a solution to overcome the difficulties of monitoring spatial heterogeneity. Then, based on the typical river valley city Baoji in Northwest China as the research object, this framework was used to analyze and predict the evolution law of heterogeneity of EV from 2000 to 2030. The findings indicate the following: (1) Synthesized ecological vulnerability index (SEVI) in 2000 and 2020 was 2.47 and 2.49, respectively, with less than 5% of the total area transitioning to areas of higher EV, indicating a relatively stable ecological environment. (2) The clustering characteristics of EV remained stable, primarily showing non‐significant, high–high, and low–low clustering, with varying degrees of heterogeneity across different regions. (3) Factors analysis revealed that DEM and LUCC had been the dominant factors of EV, and that interactions between factors were stronger than interactions within them, suggesting that its spatial heterogeneity was the result of a combination of factors. (4) The CA‐Markov model predicted a gradual improvement in the ecological environment by 2030, with a Kappa coefficient test value of 0.7733. The framework constructed in this study proposes a perspective for improved analyses of spatial heterogeneity of ecosystems, providing a viable approach to the management of regional ecological vulnerability.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sarva Mangala Praveena, Nik Munirah Nik Mohd Zaidi, Ayu Lana Nafisyah, H. G. Lingaraju
As human activities continue to increase, the production and utilisation of plastics have become pervasive, leading to a surplus of plastic waste in the environment. This has turned the terrestrial ecosystem, encompassing soil, into a significant receptacle for the growing accumulation and discharge of plastic waste. Thus, the objective of this study is to investigate the occurrence, relationships, sources and pollution levels of microplastics in urban soils from different land use activities in Cyberjaya, Malaysia. Surface soil samples were collected from land uses (i.e., vacant areas, residential areas, commercial areas, construction areas and roadways). These surface soil samples were analysed for microplastic occurrence using density separation, microscopy and spectroscopy methods. The microplastics particles were analysed for size, colour and shape. Selected microplastics particles were also analysed for its plastics polymers using Fourier-Transform Infrared Spectroscopy. Microplastics occurrence ranged from 0.3 to 1.5 particle/kg, with the highest average occurrence in the construction area (0.69 particle/kg) and lowest in the vacant area (0.33 particle/kg). Microplastics particle size was shortest in commercial areas (586.08 μm) and longest in vacant areas (793.78 μm). There were no similarities between microplastics occurrence and particle size across these different land use activities, suggesting that the microplastics occurrence in urban soils depends on external disturbances during each land use activity. Significant correlation between microplastic particle size and temperature (r2 = 0.517) showed that each land use activity is influenced by external disturbances. The Igeo values showed that the microplastics pollution level in urban soils is classified as uncontaminated to moderately contaminated. Microplastic particles in urban soils were found in various shapes (i.e., fragments, films and fibres) and colours (i.e., transparent, grey, blue, red, green, purple, black, white and yellow) along with plastic polymer types (i.e., ABS, PET, PP, PE and PS) due to traffic volume, tyre wear, mismanaged plastic waste and degradation rate. This study highlights the need for pollution management and waste disposal to avoid urban environmental problems and adverse health effects.
{"title":"Microplastics in Urban Soils From Different Land Use Activities of Cyberjaya (Malaysia): Exploring Occurrence, Relationships, Sources and Pollution Level","authors":"Sarva Mangala Praveena, Nik Munirah Nik Mohd Zaidi, Ayu Lana Nafisyah, H. G. Lingaraju","doi":"10.1002/ldr.5294","DOIUrl":"https://doi.org/10.1002/ldr.5294","url":null,"abstract":"As human activities continue to increase, the production and utilisation of plastics have become pervasive, leading to a surplus of plastic waste in the environment. This has turned the terrestrial ecosystem, encompassing soil, into a significant receptacle for the growing accumulation and discharge of plastic waste. Thus, the objective of this study is to investigate the occurrence, relationships, sources and pollution levels of microplastics in urban soils from different land use activities in Cyberjaya, Malaysia. Surface soil samples were collected from land uses (i.e., vacant areas, residential areas, commercial areas, construction areas and roadways). These surface soil samples were analysed for microplastic occurrence using density separation, microscopy and spectroscopy methods. The microplastics particles were analysed for size, colour and shape. Selected microplastics particles were also analysed for its plastics polymers using Fourier-Transform Infrared Spectroscopy. Microplastics occurrence ranged from 0.3 to 1.5 particle/kg, with the highest average occurrence in the construction area (0.69 particle/kg) and lowest in the vacant area (0.33 particle/kg). Microplastics particle size was shortest in commercial areas (586.08 μm) and longest in vacant areas (793.78 μm). There were no similarities between microplastics occurrence and particle size across these different land use activities, suggesting that the microplastics occurrence in urban soils depends on external disturbances during each land use activity. Significant correlation between microplastic particle size and temperature (<i>r</i><sup>2</sup> = 0.517) showed that each land use activity is influenced by external disturbances. The <i>I</i><sub>geo</sub> values showed that the microplastics pollution level in urban soils is classified as uncontaminated to moderately contaminated. Microplastic particles in urban soils were found in various shapes (i.e., fragments, films and fibres) and colours (i.e., transparent, grey, blue, red, green, purple, black, white and yellow) along with plastic polymer types (i.e., ABS, PET, PP, PE and PS) due to traffic volume, tyre wear, mismanaged plastic waste and degradation rate. This study highlights the need for pollution management and waste disposal to avoid urban environmental problems and adverse health effects.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Soil ecological stoichiometry (SES) provides an important approach in exploring chemical element balance relationships and ecosystem structure and function, but the characterization, significance, and drivers of SES in saline–alkali areas have not been well studied. Soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) were measured and their SES ratios were calculated from 155 soil samples collected at a depth of 20 cm in the saline–alkali soil zone of western Jilin Province, China. The results showed that SOC, TN, and TP contents and SES ratios (52:4:3) were lower in this region than in terrestrial ecosystems both in China as a whole and globally. The distribution of SOC, TN, and TP in saline–alkali soil varied significantly across land use types, with high concentrations mainly in woodland, grassland, and cropland. SOC, TN, and TP were tightly coupled, with significant positive correlations (p < 0.01), and C:N was significantly negatively correlated (p < 0.01) with the other SES ratios, indicating that saline–alkali soils are susceptible to carbon and nitrogen limitation. The distribution patterns of SOC, TN, TP, and their eco-chemometrics on the environmental gradient were variable, mainly in the form of significant decreases with increasing mean annual precipitation, mean annual temperature, and elevation. Cropland was most affected by environmental factors, and all SES except TP were affected by environmental factors. Soil nutrient (44.9%) and soil texture (9.8%) contributed the most to explaining SES in the saline–alkali soil zone, while climate (1.6%) and vegetation (0.4%) contributed the least to the explanation. All land use types were most explained by AN, except for woodland SES, which was most explained by AP. Elevation (17.4%) possessed a high degree of explanation for SES on underutilized land, except for the soil itself. Grassland is the land category most affected by climatic factors (12.7%). By applying biochar, nitrogen fertilizer, and planting saline-tolerant crops such as Leymus chinensis, the soil structure can be effectively improved and the content of carbon and nitrogen in the soil can be increased, which has a positive effect on the improvement of saline–alkali soil. The results of the study provide information that can be used to help saline–alkali areas cope with environmental and climate change and restore degraded ecosystems.
土壤生态化学计量学（SES）为探索化学元素平衡关系和生态系统结构与功能提供了一种重要方法，但对盐碱地区土壤生态化学计量学的特征、意义和驱动因素尚未进行深入研究。本研究采集了中国吉林省西部盐碱地带 20 cm 深的 155 个土壤样品，测定了土壤有机碳（SOC）、全氮（TN）和全磷（TP），并计算了它们的 SES 比值。结果表明，该地区的 SOC、TN、TP 含量和 SES 比值（52:4:3）均低于中国和全球的陆地生态系统。盐碱地土壤中的 SOC、TN 和 TP 在不同土地利用类型中的分布差异显著，主要集中在林地、草地和耕地中。SOC、TN和TP紧密耦合，呈显著正相关（p < 0.01），C:N与其他SES比率呈显著负相关（p < 0.01），表明盐碱地土壤易受碳氮限制。SOC、TN、TP 及其生态化学计量学指标在环境梯度上的分布模式是多变的，主要表现为随着年平均降水量、年平均气温和海拔高度的增加而显著降低。耕地受环境因素的影响最大，除 TP 外，所有 SES 均受环境因素的影响。土壤养分（44.9%）和土壤质地（9.8%）对盐碱地带 SES 的解释作用最大，而气候（1.6%）和植被（0.4%）对 SES 的解释作用最小。除林地 SES 由 AP 解释最多外，其他土地利用类型均由 AN 解释最多。除土壤本身外，海拔（17.4%）对未充分利用土地的 SES 有很高的解释力。草地是受气候因素影响最大的土地类别（12.7%）。通过施用生物炭、氮肥、种植耐盐碱作物如莱菔子等，可有效改善土壤结构，增加土壤中碳氮含量，对改良盐碱地有积极作用。研究结果为帮助盐碱地区应对环境和气候变化、恢复退化的生态系统提供了信息。
{"title":"Characteristics and Drivers of Soil Ecological Stoichiometry in Saline–Alkali Areas of Western Jilin Province, Northeast China","authors":"Yuefen Li, Jingfa Zhong, Lei Chang","doi":"10.1002/ldr.5306","DOIUrl":"https://doi.org/10.1002/ldr.5306","url":null,"abstract":"Soil ecological stoichiometry (SES) provides an important approach in exploring chemical element balance relationships and ecosystem structure and function, but the characterization, significance, and drivers of SES in saline–alkali areas have not been well studied. Soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) were measured and their SES ratios were calculated from 155 soil samples collected at a depth of 20 cm in the saline–alkali soil zone of western Jilin Province, China. The results showed that SOC, TN, and TP contents and SES ratios (52:4:3) were lower in this region than in terrestrial ecosystems both in China as a whole and globally. The distribution of SOC, TN, and TP in saline–alkali soil varied significantly across land use types, with high concentrations mainly in woodland, grassland, and cropland. SOC, TN, and TP were tightly coupled, with significant positive correlations (<i>p</i> < 0.01), and C:N was significantly negatively correlated (<i>p</i> < 0.01) with the other SES ratios, indicating that saline–alkali soils are susceptible to carbon and nitrogen limitation. The distribution patterns of SOC, TN, TP, and their eco-chemometrics on the environmental gradient were variable, mainly in the form of significant decreases with increasing mean annual precipitation, mean annual temperature, and elevation. Cropland was most affected by environmental factors, and all SES except TP were affected by environmental factors. Soil nutrient (44.9%) and soil texture (9.8%) contributed the most to explaining SES in the saline–alkali soil zone, while climate (1.6%) and vegetation (0.4%) contributed the least to the explanation. All land use types were most explained by AN, except for woodland SES, which was most explained by AP. Elevation (17.4%) possessed a high degree of explanation for SES on underutilized land, except for the soil itself. Grassland is the land category most affected by climatic factors (12.7%). By applying biochar, nitrogen fertilizer, and planting saline-tolerant crops such as <i>Leymus chinensis</i>, the soil structure can be effectively improved and the content of carbon and nitrogen in the soil can be increased, which has a positive effect on the improvement of saline–alkali soil. The results of the study provide information that can be used to help saline–alkali areas cope with environmental and climate change and restore degraded ecosystems.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rui Qi, Jiahao Cao, Bo Li, Ting Liu, Benqiang Gao, Siqing Wang, Zhengwei Ren, Ning Chen, Xiaowen Hu
Picea purpurea forests are a fundamental part of the coniferous forests of the Qinghai–Tibet Plateau. These forests support an extremely rich diversity of organisms while providing crucial ecological functions. Despite their importance, the species and phylogenetic diversity (PD) of these forests remain understudied. The extent to which different plant growth forms in the forest are influenced by the environment varies according to differences in the evolutionary history and characteristics of these taxa. Here, we investigate the variations in all, woody, and herbaceous plant species diversity (SD) and PD in the eastern Qinghai–Tibet Plateau's Picea purpurea forests, along with the associated environmental factors influencing these patterns. Our results show that both SD and PD exhibit similar patterns across all, woody, and herbaceous plants. Notably, mean annual precipitation, total nitrogen, and altitude were identified as the primary factors accounting for the majority of variance in SD and PD within plant communities. Specifically, we found positive correlations between SD and PD with soil total nitrogen content, while negative correlations were observed with mean annual precipitation and altitude. Furthermore, we find that the influence of environmental variables on all plants was found to be more pronounced compared to woody and especially herbaceous plants in terms of both SD and PD. Environmental factors had a direct effect on SD and PD in all woody and herbaceous plants. However, the strength of these effects varied. Importantly, our results indicate that environmental factors influence SD independently of PD. Our findings suggest that precipitation and total soil nitrogen were the most influential environmental factors affecting plant diversity across different growth forms in Picea purpurea communities. However, inferring SD from PD remains a challenging task. These findings of our study will provide guidance for forest biodiversity conservation and sustainable forest management in the Qinghai–Tibet Plateau.
{"title":"Precipitation and Soil Nitrogen as Key Drivers of Species and Phylogenetic Diversity Across Growth Forms in Picea purpurea Forests of the Eastern Qinghai–Tibet Plateau","authors":"Rui Qi, Jiahao Cao, Bo Li, Ting Liu, Benqiang Gao, Siqing Wang, Zhengwei Ren, Ning Chen, Xiaowen Hu","doi":"10.1002/ldr.5304","DOIUrl":"https://doi.org/10.1002/ldr.5304","url":null,"abstract":"<jats:italic>Picea purpurea</jats:italic> forests are a fundamental part of the coniferous forests of the Qinghai–Tibet Plateau. These forests support an extremely rich diversity of organisms while providing crucial ecological functions. Despite their importance, the species and phylogenetic diversity (PD) of these forests remain understudied. The extent to which different plant growth forms in the forest are influenced by the environment varies according to differences in the evolutionary history and characteristics of these taxa. Here, we investigate the variations in all, woody, and herbaceous plant species diversity (SD) and PD in the eastern Qinghai–Tibet Plateau's <jats:italic>Picea purpurea</jats:italic> forests, along with the associated environmental factors influencing these patterns. Our results show that both SD and PD exhibit similar patterns across all, woody, and herbaceous plants. Notably, mean annual precipitation, total nitrogen, and altitude were identified as the primary factors accounting for the majority of variance in SD and PD within plant communities. Specifically, we found positive correlations between SD and PD with soil total nitrogen content, while negative correlations were observed with mean annual precipitation and altitude. Furthermore, we find that the influence of environmental variables on all plants was found to be more pronounced compared to woody and especially herbaceous plants in terms of both SD and PD. Environmental factors had a direct effect on SD and PD in all woody and herbaceous plants. However, the strength of these effects varied. Importantly, our results indicate that environmental factors influence SD independently of PD. Our findings suggest that precipitation and total soil nitrogen were the most influential environmental factors affecting plant diversity across different growth forms in <jats:italic>Picea purpurea</jats:italic> communities. However, inferring SD from PD remains a challenging task. These findings of our study will provide guidance for forest biodiversity conservation and sustainable forest management in the Qinghai–Tibet Plateau.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142321187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Economies in the environmentally conscious era follow the 27th Conference of the Parties' commitments to attaining environmental sustainability. However, using alternative energy sources reduces arable land and diminishes land resources, severely affecting food production, exports, and overall income. This issue raises concerns about attaining a sustainable economy, which has attracted little scholarly attention in the preceding literature. The present research examines the influence of food exports, digitalization, access to clean fuel and technologies for cooking, mineral resources, and oil resources on the economic sustainability of lower-middle-income economies. Covering the latest period from 1990 to 2022, this study uses several time series estimators to analyze the aggregate data of selected economies. The empirical results suggest that the mentioned variables are cointegrated in the long run. The regression estimates showed that food exports and mineral resources are adversely associated with economic sustainability. However, access to clean fuel and technologies for cooking and digitalization significantly contributes to the region's economic sustainability. Nonetheless, the role of oil resources is insignificant but negative, which validates the resource curse phenomenon in the region. The results are robust since these estimations are validated by regression accounting for structural breaks. This study recommends investment in clean energy resources, efficient mineral resource management, and the transition to clean energy to accomplish the 27th Conference of the Parties target and attain sustainable development.
{"title":"COP27 Perspective of Food, Land Resources and Digitalization for Sustainable Economy: Novel Evidence From Lower-Middle-Income Countries","authors":"Chaowen Bi, YuFei Gan, Weizheng Wang, Pengcheng Xue","doi":"10.1002/ldr.5305","DOIUrl":"https://doi.org/10.1002/ldr.5305","url":null,"abstract":"Economies in the environmentally conscious era follow the 27th Conference of the Parties' commitments to attaining environmental sustainability. However, using alternative energy sources reduces arable land and diminishes land resources, severely affecting food production, exports, and overall income. This issue raises concerns about attaining a sustainable economy, which has attracted little scholarly attention in the preceding literature. The present research examines the influence of food exports, digitalization, access to clean fuel and technologies for cooking, mineral resources, and oil resources on the economic sustainability of lower-middle-income economies. Covering the latest period from 1990 to 2022, this study uses several time series estimators to analyze the aggregate data of selected economies. The empirical results suggest that the mentioned variables are cointegrated in the long run. The regression estimates showed that food exports and mineral resources are adversely associated with economic sustainability. However, access to clean fuel and technologies for cooking and digitalization significantly contributes to the region's economic sustainability. Nonetheless, the role of oil resources is insignificant but negative, which validates the resource curse phenomenon in the region. The results are robust since these estimations are validated by regression accounting for structural breaks. This study recommends investment in clean energy resources, efficient mineral resource management, and the transition to clean energy to accomplish the 27th Conference of the Parties target and attain sustainable development.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142317307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tillage and straw returning are promising practices to improve soil quality, especially because of the unclear controlling effects on microbial communities and functions. A 5-year field experiment in a winter wheat-summer maize cropping system was implemented in the North China Plain to address this research gap. Management practices were deep tillage, rotary tillage, and no-tillage, each with either wheat only or both wheat and maize straw returning. Shotgun metagenomic sequencing was performed to investigate the microbial community, diversity, co-occurrence network, and function in the topsoil (0–20 cm). The associations between soil physiochemical properties and microbial community characteristics were also evaluated. Rotary tillage with only wheat straw returning (RTS) significantly increased Shannon's diversity index by 0.24%–1.71% compared to other treatments. No-tillage with only wheat straw returning (NTS) showed the most stable microbial network with the highest betweenness centrality (199.09), average path distance (2.31), and modularity (0.50). NTS had the highest relative abundance of microbial carbon (C), nitrogen (N) metabolisms, and C fixation pathways. Among deep tillage practices, both wheat and maize straw returning (DTD) were more beneficial to the stability of microbial networks than only wheat straw returning (DTS), yet without improvement in microbial diversity and function. In conclusion, microbial community and function are practical predictors of variations in soil nutrient availability, and pH value in response to different tillage and residue management practices. In particular, our study provides a basis for the development of a sustainable crop residue management system.
{"title":"Microbial Community and Functions Depending on Tillage and Straw Returning Management: Consequences for Soil Health and Ecosystem Services","authors":"Qing Liu, Hongcui Dai, Liang Wang, Xin Qian, Yingbo Gao, Hui Zhang, Kaichang Liu, Zongxin Li, Kazem Zamanian","doi":"10.1002/ldr.5301","DOIUrl":"https://doi.org/10.1002/ldr.5301","url":null,"abstract":"Tillage and straw returning are promising practices to improve soil quality, especially because of the unclear controlling effects on microbial communities and functions. A 5-year field experiment in a winter wheat-summer maize cropping system was implemented in the North China Plain to address this research gap. Management practices were deep tillage, rotary tillage, and no-tillage, each with either wheat only or both wheat and maize straw returning. Shotgun metagenomic sequencing was performed to investigate the microbial community, diversity, co-occurrence network, and function in the topsoil (0–20 cm). The associations between soil physiochemical properties and microbial community characteristics were also evaluated. Rotary tillage with only wheat straw returning (RTS) significantly increased Shannon's diversity index by 0.24%–1.71% compared to other treatments. No-tillage with only wheat straw returning (NTS) showed the most stable microbial network with the highest betweenness centrality (199.09), average path distance (2.31), and modularity (0.50). NTS had the highest relative abundance of microbial carbon (C), nitrogen (N) metabolisms, and C fixation pathways. Among deep tillage practices, both wheat and maize straw returning (DTD) were more beneficial to the stability of microbial networks than only wheat straw returning (DTS), yet without improvement in microbial diversity and function. In conclusion, microbial community and function are practical predictors of variations in soil nutrient availability, and pH value in response to different tillage and residue management practices. In particular, our study provides a basis for the development of a sustainable crop residue management system.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142317308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Intercropping, particularly within legume‐based systems, has been shown to enhance yields and optimize resource use efficiency. Yet, the potential contribution of intercropping on soil microbial communities and functions to soil nutrients cycling are not fully understood. We conducted the same field experiments at Youyu (Site1) and Zhangbei (Site2) in Northern China to evaluate the impact of oat/soybean intercropping on the rhizosphere soil bacterial community structure, composition, and co‐occurrence networks. Our results indicated that intercropping significantly modified the bacterial community structure for both oat and soybean at Site1, with changes observed only in the oat community at Site2. Specifically, intercropping led to a substantial increase in the relative abundance of Bacteroidetes and Patescibacteria in the oat rhizosphere by 48.3% and 65.4% (Site1), respectively. Conversely, in the soybean rhizosphere at Site1, there was a notable decrease in the abundance of Patescibacteria and Nitrospirae by 32.4% and 40.0%, respectively. The soil bacterial functional groups demonstrated robust positive correlations with key soil parameters such as available nitrogen (Nmin), available phosphorus (Avail‐P), and the activities of nitrogen‐ and phosphorus‐acquiring enzymes in the rhizosphere. In conclusion, intercropping is an effective agricultural practice for enhancing nitrogen and phosphorus cycling by reshaping the soil bacterial community, offering a distinct advantage over monoculture practices. This insight underscores the potential of intercropping to foster sustainable soil nutrient management, highlighting the importance of integrating such practices into modern agricultural strategies to ensure long‐term productivity and environmental sustainability.
{"title":"Oat/Soybean Intercropping Reshape the Soil Bacterial Community for Enhanced Nutrient Cycling","authors":"Huaiying Ma, Jie Zhou, Junyong Ge, Kazem Zamanian, Xingyu Wang, Yadong Yang, Zhaohai Zeng, Baoping Zhao, Yuegao Hu, Huadong Zang","doi":"10.1002/ldr.5290","DOIUrl":"https://doi.org/10.1002/ldr.5290","url":null,"abstract":"Intercropping, particularly within legume‐based systems, has been shown to enhance yields and optimize resource use efficiency. Yet, the potential contribution of intercropping on soil microbial communities and functions to soil nutrients cycling are not fully understood. We conducted the same field experiments at Youyu (Site1) and Zhangbei (Site2) in Northern China to evaluate the impact of oat/soybean intercropping on the rhizosphere soil bacterial community structure, composition, and co‐occurrence networks. Our results indicated that intercropping significantly modified the bacterial community structure for both oat and soybean at Site1, with changes observed only in the oat community at Site2. Specifically, intercropping led to a substantial increase in the relative abundance of Bacteroidetes and Patescibacteria in the oat rhizosphere by 48.3% and 65.4% (Site1), respectively. Conversely, in the soybean rhizosphere at Site1, there was a notable decrease in the abundance of Patescibacteria and Nitrospirae by 32.4% and 40.0%, respectively. The soil bacterial functional groups demonstrated robust positive correlations with key soil parameters such as available nitrogen (N<jats:sub>min</jats:sub>), available phosphorus (Avail‐P), and the activities of nitrogen‐ and phosphorus‐acquiring enzymes in the rhizosphere. In conclusion, intercropping is an effective agricultural practice for enhancing nitrogen and phosphorus cycling by reshaping the soil bacterial community, offering a distinct advantage over monoculture practices. This insight underscores the potential of intercropping to foster sustainable soil nutrient management, highlighting the importance of integrating such practices into modern agricultural strategies to ensure long‐term productivity and environmental sustainability.","PeriodicalId":203,"journal":{"name":"Land Degradation & Development","volume":null,"pages":null},"PeriodicalIF":4.7,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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