Understanding the dynamic process of community diversity after grazing exclusion is crucial for the management and conservation of alpine grassland ecosystems. This study conducted a ten-year grazing exclusion experiment at four altitudinal gradients on Mount Gongga, ranging from 3000 m to 4130 m. Community diversity was surveyed at each altitude for the years 2012-2016, 2020, and 2022. We examined the changes in community diversity and species composition by mixed-effects model, principal coordinate analysis and triangular plots of β-diversity comparisons. Several key findings were revealed: 1) The mixed‐effects models showed that the interactions of altitude and time were significantly correlated with α-diversity, and the α-diversity at all altitudes shows a decline in the long-term grazing exclusion period, but the community composition at low altitudes changes at a slower pace compared to other altitudes; 2) Across all altitudinal sites, β-diversity patterns are similar initially and subsequently influenced by species replacement at 4130m with 7 new species appeared at 2022 compare to 2012, while at 3850 m, the richness difference is primary factor; 3) Species composition changes were more influenced by pioneer species (e.g., Potentilla leuconota and Plantago asiatica) at lower altitudes, whereas livestock-preferred species, such as those from the Cyperaceae and Poaceae families, played a crucial role at middle to high altitudes. These results illuminate the complexity of ecological replacement and how various factors, including altitude and grazing exclusion, influence the dynamics and composition of alpine grassland communities over time.

Soil degradation is an essential environmental problem that threatens agricultural productivity and sustainability in the typical black soil region in northeast China. Assessing the degradation status and risks of sloping cropland is necessary to restore and reconstruct degraded soil. This study aimed to map soil degradation status based on a newly developed soil degradation index (SDI) and assess the uncertainty associated with degradation risk mapping using Ordinary Kriging and Sequential Gaussian simulation (SGS). The results showed that SDI ranged from 0.013 to 0.864, with a mean value of 0.445. The realization with 200 times by SGS was the best, with an increasing pattern of SDI from north to south in the study area. Mildly degraded and moderately degraded sloping cropland accounted for 35.3% and 52.4% of the total area of sloping cropland, respectively. High-risk areas were mainly distributed in the Greater Xingan Mountains and Changbai Mountains to the Songnen Plain. Proactive measures are necessary to control and mitigate further degradation by developing soil management and weakening the interaction between slope gradient and ridge-slope angle. The developed risk assessment maps provide baseline information for regional sustainable development.

Carbon stock options to mitigate climate change have become a major area of interest across the globe. Climate change is a global issue, and every possible way to mitigate it, is being explored. Afforestation and ecosystem restoration activities are widely adopted to improve the potential of the land in carbon storage. The Kerala State Action Plan on Climate Change proposed the ‘Trees outside forests (Tof)’ as an effective mechanism to mitigate climate change. Due to its discrete distribution and non-uniformity, there are fewer attempts to measure the potential of these systems. This study tried to determine and compare the carbon (C) stock potential of the three “Trees outside forest (Tof)” conditions prevailing in the Palakkad district, Kerala. The carbon stock by standing biomass and soil of four sites of undisturbed natural vegetation, monoculture plantation, and home garden was estimated using allometric equations and computations. The natural vegetations was found to have a higher carbon stock potential (238.58 Mg ha -1) compared to monoculture plantation and human habitat. Also, natural vegetation’s soil organic carbon content was much higher than monoculture plantations and home gardens. The study also estimated the soil deterioration index of each land use compared to the natural vegetation and barren land. The results of the study suggested that land use has a great influence on soil quality and carbon stock potential. Proper management of these Tof systems can enhance their productivity and contribute accountable support towards mitigating climate change.

Microorganisms play a key role in maintaining the stability of vegetation-soil-microbial systems and terrestrial geochemical processes in alpine meadows. To investigate the effects of different management practices on the structure and function of microbial communities, the present study used metagenomic sequencing to investigate the structure and function of soil microbial communities in the southern Qilian Mountains of the Qinghai-Xizang Plateau in response to the management practices of fenestration (FE), winter grazing (WG), transition zone between natural and artificial grasslands (TZ), and artificial unicast oats (AU). The management measures significantly changed vegetation diversity and soil physicochemical properties. The prokaryotic community structure was considerably similar in FE and WG, as well as in TZ and AU. Near-natural (FE) and artificial establishment (AU) disturbances changed the fungal community structure. Enzymes related to carbon metabolism did not respond significantly to the management measures, whereas those related to nitrogen metabolism did not respond significantly in TZ and AU. The relative abundance of enzymes involved in nitrogen metabolism was higher under TZ and AU than under FE and WG. We concluded that grassland management measures altered the structure of aboveground graminoid and leguminous vegetation communities and belowground biomass allocation, resulting in changes in K uptake, causing significant changes in the structure of fungal communities and nitrogen-metabolizing enzymes; moderate disturbance (WG) was beneficial for maintaining the stability of microbial communities in alpine grasslands.

A document by Guangyong Li. Click on the document to view its contents.

The investigation of the resilience of cultivated land in primary grain producing regions, considering both natural and human characteristics, holds significant theoretical and practical importance. We aim to elucidate the feedback mechanism of regional cultivated land systems in response to various pressures and coercions, and design both a theoretical evaluation system and an econometric evaluation model of cultivated land resilience in the middle reaches of the Yangtze River in China. It analyses the spatial and temporal development of cultivated land resilience from 2001 to 2020. Additionally, we use a geographic detector to uncover the influencing mechanism of multi-dimensional factors. The research findings indicate that the cultivated land resilience index in the middle reaches of the Yangtze River has experienced a general increase of 7.2%. However, it exhibits a cyclical evolution of ”decline-recovery” in the time sequence. Additionally, the spatial pattern of cultivated land resilience is evident, with high values observed in the area extending from the middle to the surrounding areas. Furthermore, there is a positive spatial correlation between cultivated land resilience and the level of agglomeration, with a gradual increase in the agglomeration level. The spatial heterogeneity of cultivated land resilience is influenced by the interplay of various factors, resulting in a two-factor enhancement that is partially non-linear. The intensity of each factor’s role varies across different time periods, and its significance gradually transitions from ecological pressure to scale structure, ultimately leading to food security. It is determined that the utilisation of cultivated land resources at the regional scale exhibits significant environmental intricacy, temporal fluctuations, and geographical heterogeneity. Consequently, the ensuing ambiguity in food security emerges as a crucial matter that warrants consideration at the national strategic level. The examination of cultivated land resilience offers a more comprehensive framework for identifying and diagnosing the primary deficiencies within the cultivated land system at the regional level. This, in turn, improves the region’s capacity to effectively address environmental changes and mitigate development risks. Additionally, it facilitates the establishment of an optimal spatial allocation of cultivated land resources at the regional level, promoting sustainable and robust development of the cultivated land system.

Abrupt vegetation shifts indicate sudden and profound changes in ecosystem structure and function, which may lead to excessive pressures on regional water resources and thus undermine sustainability. In the context of ecological restoration and climate change, it is unclear whether large-scale abrupt vegetation shifts have occurred on the Loess Plateau and what are the differences and mechanisms associated with the effects of these vegetation changes on soil moisture content (SMC). In this study, we found that approximately 27.9% of grasslands and 24.8% of forests on the Loess Plateau experienced positive abrupt vegetation shifts from 2000 to 2020, which may be associated with the implementation of the Grassland Ecological Compensation Program (GECP) and the Natural Forest Conservation Program (NFCP). By using the climate zone method and multi-period difference-in-differences (MDID) model, we found that the effects of abrupt vegetation shifts on SMC were heavily dependent on local climate conditions. While most abrupt vegetation shifts could wet surface soil (0–7 cm), only 55.9% of grasslands and 33.9% of forests in abrupt shifts had positive effects on entire soil (0–289 cm), specifically in areas with lower precipitation and stronger evaporation conditions. In contrast, approximately 35.7% of grasslands and 37.6% of forests in abrupt shifts may exacerbate soil drying. This study fills the knowledge gap in the effects of abrupt vegetation shifts on SMC and tries to explore the underlying mechanisms, with implications for water management and ecological programs in areas with similar climate conditions.

Artisanal and Small-Scale Gold Mining (ASGM) significantly contribute to land degradation in the Amazon, carried out by individual miners or small enterprises with limited capital. This practice exerts increasing pressure on biodiversity-rich forests. Due to limited information on edaphic conditions crucial for the restoration of these degraded areas, we employed a soil evaluation method in representative sites of the Peruvian Amazon, including two native communities and one protected natural area. The categorization of ASGM degraded areas into Cultural Landscape Units (CLUs) was confirmed and validated. Sentinel-2 and UAV remote sensing revealed over 122,000 ha deforested since the 1980s. Surface and soil profile assessments identified extreme new soil conditions with low chemical and physical fertility, characterized by coarse texture and rock fragments, hindering revegetation, especially during prolonged drought seasons. These degraded soils were classified as Entisols and Technosols according to Soil Taxonomy and the World Reference Base, respectively. Over time, natural regeneration and plantations improved soil formation, aligning with recognized soil classification systems. Given the current management practices, restoration planning should prioritize selected shrub and tree species, considering soil amendments to initiate soil recovery. This approach aligns with self-sustained successional stages and contributes to the objectives of Land Degradation Neutrality (LDN), Appropriate Mitigation and Adaptation Actions (NAMAs), and Sustainable Development Goals (SDGs).

Agroecology has been addressed as one of the most prominent alternatives to achieve sustainability in agriculture, both for land and people. For this reason, academics, authorities, social leaders and organizations from many fields have urged a transition from modern conventional to agroecological agriculture. However, farms are complex systems, and this transition demands the transformation of a broad set of characteristics and practices that are a consequence of the farm administrator decisions. These are, in turn, conditioned by its specific context (social, educational, economic, political). Therefore, a clear understanding of the main drivers behind the management of farms is vital for supporting an effective transition, where the process remains stable and does not return to the previous state (conventional production) or reaches an alternative state (permanent degradation). For this reason, this research evaluated the Main Agroecological Structure (MAS) of 20 farms in different degrees of agroecological transition, in five locations of the northern-central Andean region of Ecuador. The farms had a moderately developed structure on average (71.05 over 100), and MAS variation was significantly related to the study site. One of the main differences between sites was a more extended prevalence of cooperation and development programs. For this reason, the author proposes that MAS measurements should be complemented with deeper analyses of the capacity-building background of each site. This study aims to establish a baseline of the MAS in Ecuador, and to provide new tools for monitoring agroecological transition.

Obstacles related to the continuous cropping of sweetpotato ( Ipomoea batatas (L.) Lam.) restrict its intensive production. However, the effects of continuous cropping on soil properties and/or the rhizosphere microbial community are largely unclear. In this study, we analysed changes in rhizosphere soil chemical properties and microbial communities of sweetpotato across different cultivation years. We observed that the microbial diversity and complexity of the fungal ecological network in rhizosphere soils of sweetpotato were decreased after 5 years of continuous cropping, with significant enrichment in Sphingobium, Gemmatimonas, Volutella, and Neoidriella. Tuber yield, soil pH, and available potassium (AK) content were significantly reduced after continuous cropping, with the soil microbial community having the highest correlation with pH, AK, and ammonium nitrogen (NH 4 +-N). Specifically, soil pH and AK were positively correlated with Bacillus and Gaiella, and negatively correlated with some plant-pathogenic fungi ( Volutella and Neoidriella), while NH 4 +-N showed the opposite trend. In addition, soil pH, AK, and the relative abundance of Bacillus were positively correlated with tuber yield, while Volutella showed the opposite trend. In summary, the continuous cropping of sweetpotato negatively affects rhizosphere soil health, resulting in imbalanced soil fertility and increased abundance of pathogens. These results improve our understanding of factors driving obstacles faced with the continuous cropping of sweetpotato, enabling future studies and the development of technologies to overcome these obstacles.

The Brazilian Caatinga is one of the most diverse dry forests on the planet. Half of its original coverage is degraded, and it is currently identified as one of the main areas undergoing desertification. Natural regeneration depends on climatic and edaphic conditions, as well as the adult stratum present in an area. Despite its importance, this process is little known in the Caatinga. Thus, we aimed to analyze how the anthropic disturbance, vegetation cover, and soil properties influence regenerating stratum under different Caatinga vegetation cover levels. Our study was executed in the driest region of Brazil. We classified our studied areas as Area I (less vegetation cover) and Area II (greater coverage). Six plots of 50 x 20 m were delimited for sampling the adult and regenerating stratum, and the soil in each area. Our results show interactions between soil characteristics and adult and regenerating stratum. Area II showed greater diversity and a greater number of exclusive species; in contrast, a dominance of species more resistant to limiting conditions was observed in Area I, such as Aspidosperma pyrifolium Mart. & Zucc. The C and N contents in the soil indicated a positive and significant correlation with the diversity of the regenerating stratum. The data revealed that the area with less vegetation cover, richness, and diversity presented indications of desertification.

Semi-arid alpine ecosystems on the Tibetan Plateau are experiencing rapid climate change and extensive anthropogenic activity, concomitant with the encroachment of shrubs. Shrub encroachment leads to changes in both the structure and functioning of semi-arid alpine steppes. Yet, the encroaching impacts of shrubs on the above- and belowground ecosystem functioning of the semi-arid alpine steppes remains uncertain. To quantify shrub encroachment impacts on ecosystem functioning of the semi-arid alpine steppes, two shrub encroached alpine steppe sites are investigated, with one site encroached by a leguminous shrub ( Caragana spinifera) and another site encroached by a non-leguminous shrub ( Dasiphora fruticosa). Results showed that following both Leguminosae and Non-Leguminosae shrub encroachment, not only do these alpine steppes greatly increase the individual ecosystem functions but that this included significant enhancing of the ecosystem multifunctionality (EMF). We concluded that the main impacts of shrub encroachment were to facilitate belowground EMF (BEMF) rather than aboveground EMF (AEMF) in alpine steppes. Our findings also highlight that soil nutrients play critical roles in driving ecosystem functioning responses to shrubs encroachment. These findings further our understanding of shrub encroachment impacts on ecosystem functioning of the Tibetan semi-arid alpine steppes.

The sandy Pinus sylvestris var. mongolica plantation that as the boundary part of the Three North Shelterbelt Project in Northeast China has been well protected and prohibited disturbance more than ten years, and thus bring about lots of forest floor litter and then humus layer. While humus layer accumulation that could change the interface between litter and soil, its effects on litter and soil, and especially the interaction among them were still poorly understood. Hence, three different treatments that included remove all forest floor litter and humus, double forest floor litter and humus layer, and retain forest floor litter and humus original (no treatment) were conducted, and the physicochemistry properties and microbial communities were monitored. Results showed that the humus layer increased forest floor litter decomposition rate and its total carbon, total nitrogen and total phosphorus significantly, while it changed soil pH and nutrients differently and slightly. The abundances of bacterial groups at different taxonomic levels increased and while its diversity indexes decreased in litter when the humus layer existed, however, the fungi community both in litter and soil varied insignificantly. The humus layer not only increased remarkably the proportions of common OTUs between humus and litter, humus and soil compared to litter and soil both for fungi and bacteria, but also decreased the differences of the number of fungal and bacterial taxa statistics between litter and soil. It implied that the humus layer could act an important role in the recover process of degraded forest ecosystem.

Ski tourism’s popularity is driving a rise in the number of ski resorts. This study aims to present the impact of ski infrastructure on soil erosion processes on the example from a small catchment in the Gubałowskie Foothills in southern Poland, where landscape changes before (since 1879) and after the construction of the ski station (2007) were presented. The analyses of changes in flow accumulation, slope morphometry, and drainage ditches were conducted in the test area. Quantitative analyses were performed using repeated DEMs derived from LiDAR survey and detailed geodetic measurements, complemented by geomorphological mapping done in the field. The study has revealed that the ski infrastructure has not only directly transformed the hillslope by flattening and constructing escarpments (up to 3 m high) but has also created alternating patterns of erosion and accumulation. In the test area, the drainage ditch was poorly designed. It was filled by materials (0.1–0.5 m), and two new outlets formed. The escarpment of the analyzed ski run has been diminished by 0.5 m. An alluvial fan (0.1 to 0.22 m thick) has developed on the flattened surface below the escarpment with drainage ditch outlets. This fan is eroded by subsurface flow that creates a piping system. The gully below the alluvial fan has retreated upslope, accelerated by subsurface erosion. This study enables the presentation of hillslope adjustments and processes in response to the new conditions caused by ski infrastructure. Such results may support more effective land management in regions changed by ski infrastructure.

Global food security is being threatened by the reduction of high-quality cropland, extreme weather events, and the uncertainty of food supply chains. The globalization of agricultural trade has elevated the diversification of non-grain production (NGP) on cultivated land to a prominent strategy for poverty alleviation in numerous developing nations. Its rapid expansion has engendered a multitude of deleterious consequences on both food security and ecological stability. NGP in China is becoming very common in the process of rapid urbanization, threatening the national food security. To better understand the causal mechanisms and enable governments to balance food security and rural development, it is crucial to have a clear understanding of the spatiotemporal dynamics of NGP using remote sensing. Yet knowledge gaps remain concerning how to use remote sensing to track human-dominated or -induced long-term cultivated land changes. Our study proposed a method for detecting the spatiotemporal evolution of NGP based on Landsat time series data under Google Earth Engine (GEE) platform. This approach was proposed by (1) obtaining the union of cultivated lands from multiple landcover products to minimize the cultivated land omission, (2) constructing multi-index dynamic trend rules for 3 representative types of NGP and obtaining results at the pixel level, while adopting the continuous change detection and classification (CCDC) algorithm to Landsat time series (1986~2022) to determine when the most recent change occurred, (3) minimizing the noise by object-oriented (OO) Land Use–Land Cover (LULC) classification and mode filter approaches, (4) mapping the spatiotemporal distribution of NGP. The proposed methodology was tested in Jiashan, located in Zhejiang province (eastern China), where NGP is widespread. We achieved high overall accuracy of 95.67% for NGP type detection and an overall accuracy of 85.26% for change detection of time. The results indicated a continued increasing pattern of NGP in Jiashan from 1986-2022, with the cumulative percentage of NGP increased from 0.02% to 20.69%. This study highlights the utilization of time-series data to document essential NGP information for evaluating food security in China and the method is well-suited for large-scale mapping due to its automatic manner.

Land use change-induced, accelerated soil erosion is a main driver of soil organic carbon (SOC) loss. However, soil erosion and SOC loss are not linked linearly because SOC-rich topsoil is eroded at the initial stages of degradation while horizons with lower SOC content are eroded later, but often at higher rates. To assess the contribution of soil erosion to the changing global carbon cycle, it is essential to understand how SOC changes when soil erosion accelerates. On cropland, dynamic replacement of organic carbon (OC) limits the net loss of soil OC stocks and causes a small, but steady flux of C from the atmosphere to soil and onwards landscape sinks. Rangelands, on the other hand, may loose their entire OC pool as a result of soil erosion because soils loose their productivity quickly when affected by erosion, disabling the replacement of SOC. Most rangelands have experienced erosion and degradation during the 20 th century, i.e. at the same time when greenhouse gas emissions from burning fossil fuels also increased. Distinguishing the contributions of rangeland land use change from other sources is essential for understanding the human impact on the global carbon cycle and climate during the 20 th century. The use of small farm reservoirs has been widespread in the South African Karoo during the last century. Many reservoirs have silted up and thus potentially document the soil properties during the period of sediment accumulation. This study tests the potential to reconstruct 20 th century SOC and total nitrogen (TN) change in rangeland soils. Five reservoir sediment profiles were sampled and texture, total organic carbon (TOC), TN and 137Cs of the samples were analysed and compared along the reservoir profiles. The results show that with one exception the oldest sediments contain more TOC and TN than the older ones. This indicates a loss of SOC and TN early after the dams were constructed in the 1920s and 1930s. These distinct changes also illustrate that the small reservoir sediments have the potential to reconstruct the impact of land use, soil erosion and associated SOC change in rangelands.

Land degradation (LD) is a severe and well-known global concern. Therefore, this review aimed to find broader connections between LD and the Sustainable Development Goals (SDGs). This literature review aims to synthesize the definitions, processes, assessments, and challenges associated with LD. Furthermore, we developed a universally applicable and concise definition of LD that links a wide range of contexts and studies. Specifically, we categorized LD-related processes into physical, chemical, and biological processes and synthesized 20 methods/formulas used in the assessment of LD. Finally, we synthesized the most significant challenges in the context of the resolution of LD and provided corresponding recommendations. The review also Identified the main SDG targets that LD directly affects and the role that LD in relation to the SDGs. Overall, we expect this literature review to be a valuable resource for researchers and practitioners aiming to obtain a broad and comprehensive understanding of LD. These findings should facilitate sustainable and scientifically rooted use of land resources.

Root detritusphere, i.e., the soil in vicinity of decomposing root residues, plays an important role in soil microbial activity and C sequestration. Pore structure (size distributions and connectivity of soil pores) in the detritusphere serves as a major driver for these processes and, in turn, is influenced by physical characteristics of both soil and roots. This study compared pore structure characteristics in root detritusphere of soils of contrasting texture and mineralogy subjected to >6 years of contrasting vegetation: monoculture switchgrass and polyculture prairie systems. Soil samples were collected from five experimental sites in the US Midwest representing three soil types. Soil texture and mineralogy were measured using hydrometer and X-ray powder diffraction, respectively. The intact cores were scanned with X-ray computed micro-tomography to identify visible soil pores, biopores, and particulate organic matter (POM). We specifically focused on pore structure within the detritusphere around the POM of root origin. Results showed that detritusphere of coarser-textured soils, characterized by high sand and quartz contents, had lower porosity in the vicinity of POM compared to finer-textured soils. POM vicinities in finer soils had high proportions of large (>300 μm Ø) pores, and their pores were better connected than in coarser soils. Lower porosity in outer (>1 mm) parts of detritusphere of switchgrass than of prairie suggested soil compaction by roots, and the effect especially pronounced in coarser soils. The results demonstrated that soil texture and mineralogy played a major, while vegetation a more modest, role in defining the pore structure in root detritusphere.