Ecological Security Research Articles

Global diversity of airborne pathogenic bacteria and fungi from wastewater treatment plants

Wastewater treatment plants (WWTPs) have been recognized as one of the major potential sources of the spread of airborne pathogenic microorganisms under the global pandemic of COVID-19. The differences in research regions, wastewater treatment processes, environmental conditions, and other aspects in the existing case studies have caused some confusion in the understanding of bioaerosol pollution characteristics. In this study, we integrated and analyzed data from field sampling and performed a systematic literature search to determine the abundance of airborne microorganisms in 13 countries and 37 cities across four continents (Asia, Europe, North America, and Africa). We analyzed the concentrations of bioaerosols, the core composition, global diversity, determinants, and potential risks of airborne pathogen communities in WWTPs. Our findings showed that the culturable bioaerosol concentrations of global WWTPs are 102–105 CFU/m3. Three core bacterial pathogens, namely Bacillus, Acinetobacter, and Pseudomonas, as well as two core fungal pathogens, Cladosporium and Aspergillus, were identified in the air across global WWTPs. WWTPs have unique core pathogenic communities and distinct continental divergence. The sources of airborne microorganisms (wastewater) and environmental variables (relative humidity and air contaminants) have impacts on the distribution of airborne pathogens. Potential health risks are associated with the core airborne pathogens in WWTPs. Our study showed the specificity, multifactorial influences, and potential pathogenicity of airborne pathogenic communities in WWTPs. Our findings can improve the understanding of the global diversity and biogeography of airborne pathogens in WWTPs, guiding risk assessment and control strategies for such pathogens. Furthermore, they provide a theoretical basis for safeguarding the health of WWTP workers and ensuring regional ecological security.

Construction of ecological network in Qujing city based on MSPA and MCR models.

With the rapid advancement of urbanization and industrialization, ecological patches within cities and towns are fragmented and ecological corridors are cut off, regional ecological security is threatened and sustainable development is hindered. Building an ecological network that conforms to regional realities can connect fragmented patches, protect biodiversity and regional characteristics, and provide scientific reference for regional ecological protection and ecological network planning. By taking Qilin District, the main urban area of Qujing City as an example, and using geospatial data as the main data source, based on morphological spatial pattern analysis (MSPA) and minimum cumulative resistance (MCR), this study identified ecological source areas, extracted ecological corridors, and build & optimize ecological networks. (1) All landscape types are identified based on MSPA, the proportion of core area was the highest among all landscape types, which was 80.69%, combined with the connectivity evaluation, 14 important ecological source areas were selected. (2) 91 potential ecological corridors were extracted through MCR and gravity models, there were 16 important ones. (3) The network connectivity analysis method is used to calculate the α, β, and γ indexes of the ecological network before optimization, which were 2.36, 6.5, and 2.53, while after optimization, α, β and γ indices were 3.8, 9.5 and 3.5, respectively. The combined application of MSPA-MCR model and ecological network connectivity analysis evaluation is conducive to improving the structure and functionality of ecological network.

Exploring Issues and Strategies of Rural Land Use and Environmental Protection

  Land resources play a crucial role in the overall development of society, but the irrational exploitation and use of these resources have significant adverse effects on the natural ecological environment, which is detrimental to the effective construction of a harmonious society. There is an inseparable relationship between rural land use and ecological security, and in current rural land use practices, environmental protection issues are increasingly emphasized. In some rural areas, in pursuit of short-term economic benefits, the importance of environmental protection is often overlooked, leading to excessive development and use of land resources, posing a great threat to the sustainable development of rural society. The reduction of vegetation signifies a deterioration of the ecological environment, and soil erosion leads to a decrease in land resources and a decline in land productivity, while soil degradation directly affects the growth of crops and the income of farmers. Therefore, it is essential to integrate environmental protection concepts throughout the entire process of rural land use. In the development and utilization of land resources, environmental protection requirements must be fully considered, adopting scientific and reasonable planning and measures to ensure the full utilization of land resources and achieve sustainable development of rural society.

Development of ice and snow tourism destinations in China: ecological security assessment and obstacle degree analysis

ABSTRACT This study proposes an integrated multi-criteria decision-making (MCDM) method to evaluate the ecological safety of Chinese ice and snow tourism destinations. To improve current methods, we propose an effective evaluation technique that incorporates the DPSIR model, entropy method, Delphi method, rough set, and TOPSIS method in a challenging environment. The indicator weights for the data were determined using the entropy method. The rough set matrix was constructed based on the rough set theory, and positive and negative ideal solutions were then determined. The study aimed to calculate and rank the ecological safety of six ice and snow tourism destinations in China using the modified rough-TOPSIS method. The results show that the Aoshan area is critically unsafe, the Chongli area is relatively safe, and the remaining four areas are mostly safe. The paper presents an analysis of the factors that hinder ecological security in ice and snow tourism destinations using the obstacle degree model. The results show that R22 (0.7368) has the most significant impact on Shennongjia. Additionally, S14 (0.5727) directly impedes the ecological security of Yunshangcaoyuan. The presence of P11 (0.4658) in Beidahu hampers its ecological security development.

Multi-Scenario Simulation of Land System Change in the Guangdong–Hong Kong–Macao Greater Bay Area Based on a Cellular Automata–Markov Model

As one of the four major bay areas in the world, the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) is a highly integrated mega urban agglomeration and its unparalleled urbanization has induced prominent land contradictions between humans and nature, which hinders its sustainability and has become the primary concern in this region. In this paper, we probed the historical characteristics of land use and land cover change (LUCC) in the GBA from 2005 to 2015, and forecasted its future land use pattern for 2030, 2050, and 2070, using a cellular automata–Markov (CA–Markov) model, under three typical tailored scenarios, i.e., urban development (UD), cropland protection (CP), and ecology security (ES), for land use optimization. The major findings are as follows: (1) The encroachments of build-up land on the other land uses under rapid urbanization accounted for the leading forces of LUCCs in the past decade. Accordingly, the urban sprawl was up to 1441.73 km2 (23.47%), with cropland, forest land, and water areas reduced by 570.77 km2 (4.38%), 526.05 km2 (1.76%), and 429.89 km2 (10.88%), respectively. (2) Based on the validated CA–Markov model, significant differences are found in future land use patterns under multiple scenarios, with the discrepancy magnified over time and driven by different orientations. (3) Through comprehensive comparisons and tradeoffs, the ES scenario mode seems optimal for the GBA in the next decades, which optimizes the balance between socio-economic development and ecological protection. These results serve as an early warning for future land problems and can be applied to land use management and policy formulation to promote the sustainable development of the GBA.

Exploring the Toxicity of Oxytetracycline in Earthworms (Eisenia fetida) Based on the Integrated Biomarker Response Method

Antibiotic contamination has become a global environmental issue of widespread concern, among which oxytetracycline contamination is very severe. In this study, earthworm (Eisenia fetida) was exposed to oxytetracycline to study its impact on the soil environment. The total protein (TP), catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), malondialdehyde (MDA), glutathione S-transferase (GST), and glutathione peroxidase (GPX) oxidative stress indicators in earthworms were measured, and the integrated biomarker response (IBR) approach was used to evaluate the toxic effect of oxytetracycline on earthworms. A Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) and a path analysis model were used to explore the physiological and metabolic processes of earthworms after stress occurs. The results showed that SOD, GPX, and GST play important roles in resisting oxytetracycline stress. In addition, stress injury showed a good dose–effect relationship, and long-term stress from pollutants resulted in the most serious damage to the head tissue of earthworms. These results provide a theoretical basis for understanding the toxic effect of oxytetracycline on soil animals, monitoring the pollution status of oxytetracycline in soil, and conducting ecological security risk assessment.

Trade-offs of landscape connectivity between regional and interregional ecological security patterns in a junction area of Beijing-Tianjin-Hebei region

Highly urbanized areas are confronted with insufficient space for regional ecological conservation. Therefore, the implementation of ecological conservation has shifted from region to inter-region in China. However, the effectiveness of interregional ecological conservation remains unknown. Taking Tongzhou District and the Three Northern Counties of Hebei Province (TZ&TNC) for example, the key issue was explored based on ecological security pattern (ESP) construction and an index of landscape connectivity. The results showed that 93 (73) ecological corridors connected 63 (45) ecological sources from the regional (interregional) perspective. The trade-offs in landscape connectivity between the two perspectives were obvious, and the interregional ESP enhanced the landscape connectivity of the whole study area with significantly increasing in Tongzhou and Sanhe, but decreasing in Xianghe. However, after removing 70% and 56% of the ecological sources in Tongzhou and Sanhe respectively, the importance of landscape connectivity reversed from interregional perspective to regional perspective, indicating that the effectiveness of interregional ecological conservation varied with number proportion of protected patches. This study explored the trade-offs of landscape connectivity between regional and interregional ESPs, highlighting the priority of interregional ecological conservation.

Multi-Scenario Simulating the Impacts of Land Use Changes on Ecosystem Health in Urban Agglomerations on the Northern Slope of the Tianshan Mountain, China

It is of great significance for scientific land use planning and ecological security protection to clarify the impacts of land use changes on an ecosystem’s health. Based on the dynamic evolution of land use and ecosystem health on the Northern Slope of Tianshan Mountain (NSTM) from 2000 to 2020, this study utilized the patch-generating land use simulation (PLUS) model, the Vitality–Organization–Resilience–Services (VORS) model, and the elasticity approach to assess the impacts of land use changes on ecosystem health under four different scenarios: Natural Development Scenario (ND), Farmland Conservation Priority Scenario (FP), Ecological Conservation Priority Scenario (EP), and Urban Development Priority Scenario (UD). The results indicate that (1) land use on the NSTM from 2000 to 2020 was predominantly characterized by barren land and grassland. (2) The overall level of ecosystem health on the NSTM was poor from 2000 to 2020 but showed a gradual improvement trend. (3) Ecosystem health levels vary greatly across scenarios. In general, ecosystem health improves under FP and EP scenarios but deteriorates significantly under ND and UD scenarios. The resilience of ecosystem health varies significantly across different land categories. In the future, optimizing the current land use pattern and refining the ecological protection policy are essential to enhance ecosystem health and services in the NSTM.

The Temporal and Spatial Characteristics of Ecological Security Pattern in the Loess Plateau, China

As a typical ecologically fragile area, the ecological security of the Loess Plateau has been seriously threatened. Ecological security patterns (ESP) have gradually become an effective method for protecting ecological security and supporting the management and sustainable development of ecosystems. Therefore, this study constructed a novel ESP based on ecological “function–structure”, utilizing minimum cumulative resistance (MCR) to identify ecological source areas and corridors. Additionally, time scales were introduced into the ESP, allowing for a comprehensive analysis of the spatiotemporal heterogeneity of ecological security in the Loess Plateau. The study revealed that the number of ecological sources decreased from southeast to northwest, with 27, 41, and 77 sources covering total areas of 4263.810 km2, 18,566.034 km2, and 113,209.595 km2 from 2000 to 2020, respectively. Similarly, the number and complexity of ecological corridors increased over the same time period, with 64, 85, and 105 corridors totaling lengths of 4579.326 km, 6526.996 km, and 7015.174 km, respectively. The expansion of ecological security zones was mainly observed in the southeast part of the Loess Plateau. Overall, the ESP of the Loess Plateau saw an improvement, with the southeastern part showing better ecological security than the northwestern part. These findings hold great significance for regional ecological security evaluations and are crucial for promoting ecological management and healthy development in the Loess Plateau.

Quantifying the impacts of climate change and human activities on ecological flow security based on a new framework

AbstractClimate change and human activities combine to alter river hydrology, thereby threatening the health of river ecosystems. Quantifying the impacts of climate change and human activities on ecological flow assurance is essential for water resource management and river ecological protection. However, fewer studies quantify the impacts of climate change and human activities on ecological flow assurance based on a complete set of frameworks. The present study introduces an integrated assessment framework designed to quantify the impacts of climate change and human activities on ecological flow security. The framework includes the following steps: (1) natural river runoff reconstruction utilizing a semi‐distributed hydrological model (SWAT), (2) calculation of the most suitable ecological stream flow of the watershed ecosystem by using the non‐parametric kernel density estimation method, (3) calculation of the safety and security levels under minimum ecological flow and appropriate ecological flow conditions in the watershed and (4) quantification of the influences of climate change and human activities on the security of ecological flow in the watershed through the application of a quantitative attribution method. The impact of climate change and human activities on the ecological flow assurance level was analysed using three hydrological stations in Xiangtan, Hengyang and Laobutou, which are the main tributaries of the Xiangjiang River Basin, as a case study. The findings indicated a substantial decrease in ecological flow assurance levels across the basin during the period of human impact (1991–2019). The quantitative assessment results suggest that human activities predominantly drive the degradation of ecological flow assurance throughout the period of human impact, accounting for 57.05% of the total impact. Extensive gradient reservoir scheduling and anthropogenic water withdrawals were the main factors contributing to the degradation of ecological flow assurance in the study basin. The methodology and findings presented in this study offer insights into the evolutionary characteristics and driving forces behind ecological flow security in a dynamic environment. Furthermore, they establish a scientific foundation for local water resource management and river ecosystem protection.

Dynamic transcriptome profiling revealed a key gene ZmJMJ20 and pathways associated with cadmium stress in maize

Cadmium (Cd) pollution in soil poses a global concern due to its serious impacts on human health and ecological security. In plants, tremendous efforts have been made to identify some key genes and pathways in Cd stress responses. However, studies on the roles of epigenetic factors in response to Cd stress were still limited. In the study, we first gain insight into the gene expression dynamics for maize seedlings under 0 h, 12 h, and 72 h Cd stress. As a result, six distinct groups of genes were identified by hierarchical clustering and principal component analysis. The key pathways associated with 12 h Cd stress were protein modifications including protein ubiquitination, signal transduction by protein phosphorylation, and histone modification. Whereas, under 72 h stress, main pathways were involved in biological processes including phenylalanine metabolism, response to oxygen-containing compounds and metal ions. Then to be noted, one of the most highly expressed genes at 12 h under Cd treatment is annotated as histone demethylases (ZmJMJ20). The evolutionary tree analysis and domain analysis showed that ZmJMJ20 belonged to the JmjC-only subfamily of the Jumonji-C (JmjC) family, and ZmJMJ20 was conserved in rice and Arabidopsis. After 72 h of Cd treatment, the zmjmj20 mutant created by EMS treatment manifested less severe chlorosis/leaf yellowing symptoms compared with wild-type plants, and there was no significant difference in Fv/Fm and φPSII value before and after Cd treatment. Moreover, the expression levels of several photosynthesis-related down-regulated genes in EMS mutant plants were dramatically increased compared with those in wild-type plants at 12 h under Cd treatment. Our results suggested that ZmJMJ20 plays an important role in the Cd tolerance response pathway and will facilitate the development of cultivars with improved Cd stress tolerance.

Mediatization of the Ecological Security in the English Media: Corpus-Assisted Approach

Introduction. The relevance of the work is due to the interest of linguistics in the issues of  discursive mediatization of socially significant phenomena in the English-language media, in  particular environmental safety as the most important value of modern society. The scientific  novelty of the study lies in establishing the content of the value “environmental safety” on  the basis of systematization and quantification of semantic fields that are correlated with the  main topics that determine the interpretation of this socially significant phenomenon in the  British media and form a discourse-based thesaurus of its representation. Methodology and sources. The paper used corpus linguistics methods and the  interpretative method of discourse analysis. The empirical basis of the study was a corpus  of media texts of high-quality and popular media devoted to environmental safety issues,  the corpus size was more than 200 thousand words. Results and discussion. Based on corpus analysis, semantic fields were identified that  represent the concept under study in the high-quality and popular British press. It is shown  that in the media narratives of the British media, ES is closely associated with climate change  and global warming. It was revealed that the dominant topics in narratives about  environmental security in both types of media are: 1) the environment; 2) science; 3) politics.  A comparative analysis of the semantic fields showed the predominance of the semantic  field “science” in high-quality media, which indicates rational and logical strategies for  influencing a wide readership. In the texts of popular media, the semantic field “politics”  dominates, which indicates the politicization of the discourse of environmental safety and  indicates a strategy of emotional impact on the addressee. Both corpora emphasize the  issues of climate change, related to unfavourable weather conditions and extremely high  temperatures, however, high-quality press texts mention temperature anomalies much  more often, which indicates an attempt to arouse public concern about the existing threat  and encourage the adoption of necessary measures. Conclusion. The proposed methodology can be used in analyzing the specifics of other  media discursive practices in terms of their discursive-textual organization, in studying the  rhetorical, pragmatic and linguocultural organization of environmental safety discourse in  sociocultural and ideological perspectives.

Spatial and temporal evolution analysis of ecological security pattern in Hubei Province based on ecosystem service supply and demand analysis

Realizing the superior stability of natural resources for regional economic growth depends on the construction of the Ecological Security Pattern (ESP)11the Ecological Security Pattern (ESP).. The ESP of Hubei Province was determined based on the supply and demand of ecosystem services (ESSD)22the supply and demand of ecosystem services (ESSD).. The main conclusions are as follows: (1) The overall supply of ecosystem services in Hubei Province exceeds the demand, and the imbalance between supply and demand in Wuhan, Xiangyang and Jingzhou is the most serious. (2) The largest ecological source area in 2000 was 90,506 km2, followed by 86,946 km2 in 2020. (3) 11 long-term ecological obstacles with a total area of 312.96 km2 were identified, which were mainly composed of large areas of cultivated land and water. (5) The ecological protection and restoration pattern of “two axes, three belts, four districts and five cores (two main and three secondary)” has been constructed in Hubei Province. The results of this study provide reference for the management and protection of regional ecosystem and the overall response to ecological problems in Hubei Province.

Does ecological network affect the construction land spatial development intensity? -An empirical study based on the main urban area of Jinan, China

The ecological network as the cornerstone of urban ecological security protection, understanding the interaction between ecological network and construction land spatial development intensity (CLSDI), which is crucial for guiding the orderly utilization of territorial space and promoting regional sustainable development. However, the information on the complex spatial and temporal interactions between ecological networks and CLSDI has not yet been adequately studied. This study takes the main urban area of Jinan City as an example, and explores the spatial and temporal coupling relationship and change rule of ecological network and CLSDI during 2006–2018 through spatial multiple buffer analysis tools, and proposes the optimization path of construction land spatial development under the perspective of ecological network. The results showed that: from 2006 to 2018, there is a significant spatial effect between CLSDI and ecological network elements; within the buffer zone of 300–3000 m for ecological sources and nodes, CLSDI rises with the increase of buffer zone distance; while the ecological corridor exhibits decreased CLSDI within the 500-m buffer zone, the 500–3000-m CLSDI tends to increase. Based on the empirical analysis, the optimization path of construction land spatial development is proposed from three aspects: ecological source, corridor and node. The 300 m control range of the ecological source is designated as a “specific protection zone”, and strictly control the increase of the CLSDI within the zone; the ecological corridor is set up with differential protection and utilization zoning, and CLSDI and activity types are controlled in a hierarchical and classified manner; the CLDSI around the ecological nodes is strictly controlled in order to prevent encroachment of construction activities on the nodes. This study provides a reference value for constructing a territorial spatial pattern coordinated with ecological protection and development of construction.

Integrating policy quantification analysis into ecological security pattern construction: A case study of Guangdong–Hong Kong–Macao Greater Bay Area

The construction of an ecological security pattern (ESP) is an important undertaking in ensuring the stability of the ecosystem and the long-term growth of humanity. Existing research, However, existing research often overlooks the quantification of policy implications in ESP development. The objective of this paper was to bridge this gap by integrating policy quantification analysis (PQA) with nature, society and into ESP construction and providing targeted ecological management recommendations. The policy texts were quantified into reusable research data, which served as a foundation for the selection of indicators and the optimization of ecological security patterns, by using machine learning techniques. The methodology “Patch-matrix-corridor” was used to create a spatially correlated ecological security pattern. Through factor analysis and Random Forest (RF), the impact of each indicator on ecological security was thoroughly examined, offering substantial support for policy development and ESP construction planning. The Guangdong-Hong Kong-Macao Greater Bay Area(GBA) was selected as the study area, the study found that: (1) The proposed framework PQA based-ESP could provide a useful eco-management tools. (2) Policy adaptability had a substantial impact on environmental security in the GBA, but the ecosystem service index has the highest impact. (3) Applying the framework, we identified a total of 1,993 km2 of ecological sources, 23 key ecological corridors, 58 general ecological corridors, and 31 ecological nodes. An improved ESP, characterized as “one circle, two bays, three rivers, multiple areas, corridors, and nodes,” was constructed in the GBA. (4) Given the multi-scale analysis, tailored ecological management policy recommendations were proposed for each city in the GBA. The study's findings offer actionable solutions for the international community facing growing ecological challenges.

Interannual succession of phytoplankton community in a canyon-shaped drinking water reservoir during the initial impoundment period: Taxonomic versus functional groups

During the initial impoundment period of a canyon-shaped reservoir, the water body fluctuated violently regarding water level, hydrological condition, and thermal stratification. These variations may alter the structure of phytoplankton community, resulting in algal blooms and seriously threatening the ecological security of the reservoir. It is of great significance to understand the continuous changes of phytoplankton in the initial impoundment period for the protection of reservoir water quality. Therefore, a two-year in-situ monitoring study was conducted on water quality and phytoplankton in a representative canyon-shaped reservoir named Sanhekou and the interannual changes of phytoplankton community and its response to environmental changes during the initial impoundment period were discussed at taxonomic versus functional classification levels. The results showed that the total nitrogen and permanganate index levels were relatively high in the first year due to rapid water storage and heavy rainfall input, and the more stable hydrological conditions in the second year promoted the increase of algae density and the transformation of community, and the proportion of cyanobacteria increased significantly. The succession order of phytoplankton in the first year of the initial impoundment period was Chlorophyta-Bacillariophyta-Chlorophyta, or J/F/X1-P/MP/W1-A/X1/MP, respectively. And the succession order in the second year was Cyanobacteria/Chlorophyta-Bacillariophyta-Chlorophyta, or LM/G/P-P/A/X1-X1/J/G. Water temperature, relative water column stability, mixing depth, and pH were crucial factors affecting phytoplankton community succession. This study revealed the interannual succession law and driving factors of phytoplankton in the initial impoundment period and provided an important reference for the operation management and ecological protection of canyon-shaped reservoirs.

A sensitive fluoroimmunoassay for quantitative detection of imidacloprid based on quantum dot-streptavidin conjugate

Imidacloprid (IMI), the most commonly used neonicotinoid, is widely present in both the environment and agro-products due to extensive and prolonged application, posing potential risks to ecological security and human health. This study introduced a sensitive and rapid fluorescence-linked immunosorbent assay, employing Quantum Dot-Streptavidin conjugate (QDs-SA-FLISA), for efficient monitoring of IMI residues in agro-products. Under optimized conditions, the QDs-SA-FLISA exhibited a half-maximal inhibition concentration (IC50) of 1.70 ng/mL and a limit of detection (LOD, IC20) of 0.5 ng/mL. Investigation into the sensitivity enhancement effect of the QDs-SA revealed that the sensitivity (IC50) of the QDs-SA-FLISA was 7.3 times higher than that of ELISA. The recoveries and relative standard deviation (RSD) ranged from 81.7 to 118.1 % and 0.5–9.4 %, respectively, for IMI in brown rice, tomato and pear. There was no significant difference in IMI residues obtained between QDs-SA-FLISA and UHPLC-MS/MS. Thus, the QDs-SA-FLISA represents a reliable approach for the quantitative determination of IMI in agro-products.

Removal of pesticide acetamiprid using KOH activated biochar derived from crayfish shell: Behavior and mechanism

Over the past few decades, the excessive use of pesticides has resulted in serious environment pollution, and residual pesticides prompt significant concern regarding their potential harm to both the ecological security and human health. In this study, KOH activated crayfish shell biochar (KBC) was successfully prepared and used to effectively remove acetamiprid (ACE) and triadimefon (TDM) from aqueous solutions. Batch experiments results indicated that, the adsorption process of ACE was predominantly by chemical reaction and controlled by multiple mechanisms, and ACE adsorption was a thermodynamically spontaneous and exothermic reaction. The KBC exhibited exceptional adsorption performance in removing ACE with a maximum adsorption capacity of 40.41 mg g−1. A superior adsorption capacity toward both ACE and TDM over KBC could be achieved at lower concentration levels, and KBC exhibited good reuse for the removal of ACE and TDM. Different adsorption models and characterization results revealed the adsorption mechanism of ACE and TDM by KBC, including van der Waals forces, pore filling, hydrogen bonding, and π-π electron donor-acceptor interactions. These findings suggested that KBC was an excellent adsorbent for removing pesticide-contaminated water.

High-resolution physicochemical dataset of atmospheric aerosols over the Tibetan Plateau and its surroundings

Abstract. Atmospheric aerosol in the Tibetan Plateau (TP) and its surroundings has attracted significant scientific interest in recent decades due to its notable impacts on regional climatic and cryospheric changes, ecological and environmental security, and the hydrological cycle. However, our understanding of the atmospheric aerosol in this remote region is highly limited by the scarcity of available datasets owing to the extremely harsh natural conditions. This challenge has been mitigated in recent decades by establishing field observatories at typical sites within the TP and its surroundings. A continuous project initiated in 2015 aims to explore the properties and sources of atmospheric aerosols, as well as their regional differences, through multiple short-term intensive observations obtained across this vast region utilizing a suite of high-time-resolution online instruments. This paper presents a systematic and hourly scale dataset of aerosol physicochemical and optical properties at eight sites across the TP and its surroundings that is derived from the project. It includes size-resolved chemical compositions of submicron aerosols, high-resolution mass spectra and sources of organic aerosols, size distributions of particle number concentrations, particle light-scattering and light-absorption coefficients, particle light absorptions attributed to different carbonaceous substances including black carbon and brown carbon, and number concentrations of cloud condensation nuclei. In brief, atmospheric aerosols in these remote sites were all well mixed and highly aged, reflecting their dominant regional transport sources. However, the southern TP region exhibited high contributions of carbonaceous organic aerosols, neutralized bulk submicron aerosols, and a relatively high light-absorption capacity, whereas in the northern TP region, secondary inorganic species were the main contributors to the overall acidic submicron aerosols. Beyond providing insights into the regional differences in aerosol sources and properties across the TP and its surroundings, the datasets will also benefit simulations of aerosol radiative forcing and evaluations of interactions among different Earth system components in numerical models for this region. The datasets are accessible through the National Cryosphere Desert Data Center, Chinese Academy of Sciences (https://doi.org/10.12072/ncdc.NIEER.db2200.2022; Xu, 2022).

Construction of the Ecological Security Pattern in Xishuangbanna Tropical Rainforest Based on Circuit Theory

Urban modernization and economic globalization have led to significant changes in traditional natural landscapes. The unregulated and large-scale expansion of rubber plantations in Xishuangbanna has resulted in water and scenic forests being replaced by rubber forests and the complex rainforest ecosystem being replaced by simple artificial forests. This has resulted in increasingly prominent ecological problems such as soil erosion, regional microclimate changes, and sharp declines in biodiversity. The ecological security pattern is an important way to protect regional ecological sustainability. Taking the tropical rainforest in Xishuangbanna as an example, this study identified ecological sources through the evaluation of the importance of ecosystem services, constructed resistance surfaces through ecological sensitivity evaluation, and used circuit theory to simulate ecological processes in heterogeneous landscapes by calculating “electricity” or “resistance”, thereby identifying ecological corridors and key ecological nodes. The results identified 31 ecological source areas, 65 key ecological corridors, 7 potential ecological corridors, 37 ecological pinch points, and 99 ecological barriers. The overall distribution of ecological sources was scattered, with higher density in the northwest and southeast regions. Ecological corridors were distributed along high mountains, and both ecological sources and corridors were mainly composed of forest land. Based on circuit theory, this study filled the gap in the MCR model’s inability to identify the true width of corridors due to ignoring the randomness of biological migration. It determined the spatial range of ecological corridors and the specific locations of ecological nodes and barriers, providing a reference for solving ecological problems in Xishuangbanna, such as “rainforest fragmentation”.