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Table of Content

Volume 40 Issue 1
25 January 2024
Research on the Technical System of Ecological Risk Assessment of Soil Contamination in Anglo-American and Its Enlightenments
LI Yi-jie, XU Qiu-yun, KE Ling-jie, SHI Ya-juan, SHAO Xiu-qing
2024, 40(1):  1-10.  doi:10.19741/j.issn.1673-4831.2022.0896
Abstract ( 111 )   HTML ( 16)   PDF (1869KB) ( 175 )  
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With the development of economy, a large number of hazardous wastes produced by human activities are discharged into soils, causing serious soil contamination. Ecological risk assessment (ERA) is a method system for predicting the impact of risk source on surrounding ecosystem. As an important basis of risk management and soil contamination remediation, ERA determines whether risk management or remediation measures should be conducted as well as the goal of such measures. Due to the different focuses of researches, many ERA technical systems emerged continuously. The United States and the United Kingdom have years of experience in the management of contaminated sites, and have developed systematic ERA related technical guidelines and regulations with mature supporting technologies. Their experience can help superintendents in China scientifically analyze the impact of soil contamination on environment from the perspective of ecosystem. This study analyzed the present status of soil contamination related ERA in China, and investigated the workflow of ERA technical system for soil contamination in the United States and the United Kingdom. It is concluded that four key points should be noted when constructing local ERA technical system for soil contamination in China: (1) Developing tiered ERA technical system; (2)Constructing complete conceptual models from contaminants exposure to having ecological effects on receptors for ERA of contaminated sites; (3)Strengthening the analysis of the causal and effect relationship between contaminants and the ecological effects on receptors; (4)Improving decision-making participation in the ERA process; (5)Promoting toxicological research on native species. The aim of this study is to promote the construction of ERA technical system of soil contamination, guarantee the implementation of the assessment process, direct the follow-up risk management or remediation of contaminated sites, and promote the sustainable and safe utilization of soil resources in China.
Research Progress and Hot Spot Analysis on Antibiotic Resistance Gene Pollution in Soil Environment
LI Ze-kai, HAN Miao, QIN Chao, HU Xiao-jie, GAO Yan-zheng
2024, 40(1):  11-22.  doi:10.19741/j.issn.1673-4831.2022.0793
Abstract ( 102 )   HTML ( 12)   PDF (20749KB) ( 153 )  
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In recent years, antibiotic resistance genes (ARGs) in soil environments have attracted widespread attention. A bibliometric analysis was conducted using the Web of Science core database and Wanfang database as data sources to analyze the researches on ARGs contamination in soil environments from the aspects of annual publication volume, contributions from different countries, and the evolution of research topics (based on keywords). The aim was to explore the current status, hotspots, and development trends in this domain both domestically and internationally. The results show a rapid increase in the number of publications annually on ARGs contamination in soil. Chinese literature had a significant impact in terms of publication volume and citation frequency, indicating its strong international academic influence in this field. Keyword clustering analysis revealed that the current researches in this field have been mainly focused on the following areas: (1) microorganisms carrying ARGs in the soil environments; (2) source and persistence of ARGs in soil environments; (3) transmission and reduction methods of ARGs in soil environments; (4) the influence of coexisting substances in soil on the abundance and migration behavior of ARGs; (5) the impact of agricultural production activities on ARGs contamination in soil environments. Additionally, commonly used detection methods for ARGs were introduced, the sources and distribution of ARGs contamination in soil environments were also analyzed. Various factors influencing the spread of ARGs were analyzed, and methods for reducing ARGs in soil environments were discussed. Current shortcomings and future research directions in this field have been pointed out. This article can serve as a reference for future research and risk management in the field of ARGs contamination in soil environments.
Spatial Distributions and Factors of Phthalic Acid Esters in Agricultural Soils in China: A Review
SHI Chen-xue, WU Qian-qian, LIU Quan-li, ZHAO Jian, ZHOU Jun-li, REN Jia-guo, LIU Yue
2024, 40(1):  23-35.  doi:10.19741/j.issn.1673-4831.2022.0715
Abstract ( 85 )   HTML ( 4)   PDF (1354KB) ( 104 )  
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Phthalic acid esters (PAEs) are extensively used as additives in agricultural inputs (e. g., plastic films and pesticides) and classified as endocrine disrupting chemicals with the effects of carcinogenicity, teratogenicity, and mutagenicity. In recent years, as China is one of the largest consumers of plastic products, PAEs have become the dominant organic constituents in Chinese agricultural soils. Therefore, it is of great significance to understand the current enrichment status of PAEs prior to identify appropriate remediation methods. Based on the systematic review of the usage of agricultural plastic film, the survey data of PAEs pollution in agricultural soil in the different regions of China and the concentrations of various types of PAEs in different vegetables, this paper summarized the pollution degree and the distribution characteristics of PAEs in agricultural soil at the national scale. Through statistical analysis, the relationship between the PAEs concentrations in agricultural soil and the amount of agricultural film used, and the land uses associated with crop types were obtained in typical regions in China. The results show that: (1) the concentrations of PAEs in agricultural soils in most regions are generally at higher levels with a significant regional discrepancy. The most frequently detected and the most abundant congeners are di-n-butyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP). (2) The different congeners of PAEs have unique transverse and vertical distribution patterns. (3) The distribution of phthalic acid esters in agricultural soils is determined by factors such as plastic film mulching, agrotype, soil types, and properties of PAEs, etc.
Research Progress of Methods for Detection of Microplastics in Environment
SUN Yan-min, GAO Hui-min, XU Chun-xiang, YAN Chun-rong
2024, 40(1):  36-43.  doi:10.19741/j.issn.1673-4831.2022.0833
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Microplastics is a class of new global environmental pollutant. Researchers have paid great attention to the impact of microplastics on the environment and the food chain. It is difficult to precisely detect microplastics in environment due to its special physi-chemical structure, but the reliable determination methods are critical for environmental behavior research of microplastics. This review summarizes research progress of environmental microplastics from the perspective of research background, pretreatment and detection methods. The advantages and disadvantages of different methods have also been analyzed. The future researches on microplastics detection techniques are proposed to provide reference for the environmental microplastics research in the future.
Evolution and Tradeoff/Synergy Relationship of Ecosystem Services Value in Cascade Hydropower Project Reservoir Area of the Lower Reaches of Jinsha River
ZHAO Xu, WANG Hao, ZHAO Zhi-long, ZHAO Fei-fei
2024, 40(1):  44-54.  doi:10.19741/j.issn.1673-4831.2022.0660
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Based on the change index of ecosystem services, correlation analysis and spatial autocorrelation, this paper quantitatively analyzed the value of ecosystem services in the reservoir area from 2005 to 2018 and explored the spatio-temporal evolution of the synergy relationship of ecosystem services in the reservoir area. The results show that: (1) The ecosystem services value in the reservoir area reached to 94 billion yuan in 2018, with an increase of 4.2 billion yuan during the study period from 2005 to 2018. (2) The spatial distribution of ecosystem service value in the reservoir area is stable, showing a pattern of high in the south and low in the north, and the spatial correlation types are all positively correlated. The increasing areas of ecosystem services value are concentrated on the riparian zone of Jinsha River. (3) Supporting services of the ecosystem services value in the reservoir area has a tradeoff relationship with provisioning services, regulating services and cultural services, and the relationships between provisioning services, regulating services and cultural services are all synergistic, and the correlation of ecosystem services between the townships is mainly synergistic. The results further prove that the implementation of hydropower projects can improve the ecosystem service function of the reservoir area and provide technical support for environmental protection and sustainable utilization of land resources in the reservoir area.
Spatial and Temporal Evolution of Land Use Conflicts and Their Key Influencing Factors in the Changjiang River Basin
CHEN Li-ting, CAI Hai-sheng
2024, 40(1):  55-67.  doi:10.19741/j.issn.1673-4831.2022.0908
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A comprehensive scientific understanding of the spatial and temporal evolution of land use conflicts, as well as the identification of their key influencing factors, holds immense significance for promoting regional sustainable development. Taking Changjiang River Basin as the study area, where exists obvious conflicts on soil and water resources, a quantitative model of land use conflicts was constructed by using the landscape pattern index to reflect the changes in the spatial location and intensity of land use conflicts in the basin from 2000 to 2020. Additionally, the random forest model was utilized to identify the important influencing factors, and biased dependency graphs were employed to illustrate the marginal responses of these factors to the changes in land use conflict intensity. The results show that (1) the overall land use conflicts in the Changjiang River Basin were basically controllable from 2000 to 2020. High conflict values were distributed around the urban areas and along both sides of the river system. The urban-rural intertwining zone emerged as the primary spatial unit of conflict, with notable competition for water resources within the basin. The overall conflict intensity exhibited a pattern of midstream > downstream > upstream. (2) Among the influencing factors, social anthropogenic disturbances such as distance from major roads, population density, and water resource conditions such as average annual precipitation and distance from major water systems played key roles in the change of land use conflict intensity. (3) A nonlinear response relationship existed between the influencing factors and land use conflict intensity, with the agglomeration effect of the population and the constraints of the natural background being significant reasons for this nonlinearity. The Changjiang River Basin needs to develop a reasonable water allocation plan, and at the same time, strictly control the urban-rural land use conflicts brought about by excessive socio-economic development.
Distribution Characteristics and Ecological Risk Assessment of Vanadium and Chromium in Soil-fishpond-river System around Vanadium Titanium Magnet Smelting Slag Field
SHAO Bo-lin, ZHU Dian-mei, LING Kai, SUN Jia-ning, CHENG Xin, ZHONG Ke-yi
2024, 40(1):  68-77.  doi:10.19741/j.issn.1673-4831.2022.1063
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To investigate the impact of V and Cr from smelting slag on the surrounding environment, samples of soil, sediment, pond bottom mud, pond water and river water were collected. The concentration and occurrence form of V and Cr were analyzed, and their pollution status and ecological risk of V and Cr were evaluated by using enrichment factor method, geological accumulation index method and potential ecological risk index method. The study reveals that the mean concentrations of V and Cr in the soil of the study area were 2.6 and 4.0 times of the background value in Sichuan Province, with slight and moderate degrees of enrichment. Additionally, the mean concentrations of V and Cr in the sediment were 5.0 and 3.2 times of those in the control sediment, while the mean concentrations of V and Cr in the pond bottom mud were 5.5 and 1.4 times of those in the control, respectively. The degree of V and Cr enrichment was moderate and slight. The water samples exhibited V pollution, and the average concentration of V in fishpond and Baguan River water being roughly 17.6 and 1.8 times of that of Jinsha River water samples, respectively. In the study area, V and Cr primarily exist in the residual fraction in the soil, accounting for 57.1% and 89.4%, respectively. The residual fraction of V and Cr in the sediment and pond bottom mud accounts for 20.1% and 74.9%, respectively. The bioavailability and mobility of V in each environmental medium of the study area is much higher than that of Cr. Combined with the analysis of the geochemical properties of V and Cr, V and Cr in the environmental medium of the study area may exist mainly in the form of V5+ and Cr3+. The pollution evaluation results indicate that the contamination levels of V and Cr in the soil were slight and moderate, whereas both V and Cr in sediment showed slight and moderate contamination. Consequently, both V and Cr pose a slight risk to the ecosystem. Therefore, it is imperative to remediate the contaminated soil and sediment promptly to safeguard the ecosystem and public health in the study area.
Effect of Long-term Alfalfa Cultivation on Soil Carbon, Nitrogen and Phosphorus Nutrient Transformation in Reclaimed Lands
MING Yu-fei, ZHU Tao-chuan, ZHANG Jin-hao, LI Chuan-fu, GAO Shu, XU Jia-lin, LI Yong-qiang, JIAO Shu-ying
2024, 40(1):  78-86.  doi:10.19741/j.issn.1673-4831.2022.1036
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In order to study the effect of long-term planting of alfalfa on soil quality improvement three land uses were selected including the alfalfa land planted for 15 years adjacent to crop land and abandoned land, to determine the contents of soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) and their fraction contents, and analyzed the stoichiometric characteristics. The results show that long-term planting of alfalfa can significantly reduce the soil electrical conductivity (EC), and increase the content of soil available nutrients (P<0.05). Compared with crop land and abandoned land, planting alfalfa significantly increased the contents of soil SOC and TN (P<0.05), but the content of soil TP in 0-20 cm was significantly lower than that in crop land. The stoichiometric difference was significant in 0-20 cm soil of the three land uses. The C/N in alfalfa land was significantly lower than that in crop land and abandoned land (P<0.05), while it was the opposite for C/P and N/P. Planting alfalfa is helpful to improve the content of active fractions of SOC and nitrogen. The contents of particulate organic carbon (POC), readily oxidizable organic carbon (ROC) and microbial biomass carbon (MBC) in 0-20 cm soil layer were significantly higher than those in crop land by 88.38%, 17.24% and 39.16%, respectively (P<0.05). The contents of particulate organic nitrogen (PON), microbial biomass nitrogen (MBN) and acid hydrolyzed organic nitrogen in alfalfa land were the highest. Compared with crop land and abandoned land, the contents of PON and MBN in alfalfa land were significantly higher by 135.29%, 17.39% and 207.69%, 28.41%, respectively. Therefore, the long-term planting of alfalfa can actively improve and enhance soil quality and the active fractions of organic carbon and nitrogen. The research results could provide reference for the remediation of degraded land and the improment of soil quality for reclaimed land.
Phytoplankton Community Characteristics of Tongshanyuan Reservoir in Spring and Summer and Its Relationship with Environmental Factors
ZHOU Han, CAI Mei, WANG Yuan-yuan, SU Jing-hua, HUANG Ruo-han, WU Jun-chi, WANG Li-qing, ZHANG Wei
2024, 40(1):  87-95.  doi:10.19741/j.issn.1673-4831.2022.1015
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Tongshanyuan Reservoir is a storage reservoir in Quzhou City, Zhejiang Province, which plays an important role in agricultural irrigation and hydroelectric power generation. In order to understand the characteristics of the phytoplankton community structure and its relationship with water environmental factors, water samples were collected from Tongshanyuan Reservoir in March, May and July 2021. The results show that 92 species of phytoplankton belonging to 7 phyla and 57 genera were identified. The dominant species were Cyclotella sp., Eudorina sp., Coelastrum reticulatum, Microcystis spp. and Aphanizomenon flos-aquae. Principal coordinate analysis (PCoA) show that the phytoplankton community structure was significantly different over the three mouths. The seasonal succession of the phytoplankton community structure in Tongshanyuan Reservoir changed mainly from Bacillariophyta/Chlorophyta to Cyanophyta and to Chlorophyta/Cyanophyta. Shannon-Wiener diversity index (H') indicate that the reservoir was moderately polluted. The abundance and biomass of phytoplankton decreased in May, but rose again in July. Canonical correspondence analysis (CCA) show that water temperature, total nitrogen and total phosphorus were the main environmental factors affecting the phytoplankton community structure in the Tongshanyuan source. The top-down effect of zooplankton was stronger in May. But the density and biomass of zooplankton had no significant effect on the changes in phytoplankton community structure. This study provides reference and basic data for understanding and maintaining the ecology of Tongshanyuan Reservoir.
Spatial Distribution Characteristics and Influencing Factors of CH4, CO2 Emission Fluxes in Jialing River (the Section of Sichuan) during Normal Season
WU Xi-qiao, LIU Chao-rong, HUANG Xing, LUO Dan, QUAN Qiu-mei, YANG Yan
2024, 40(1):  96-106.  doi:10.19741/j.issn.1673-4831.2022.0957
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Rivers are important sources of greenhouse gas emissions in inland waters of terrestrial ecosystems. In recent years, the emission of greenhouse gases has increased the seriousness of environmental problems. This paper focuses on the Sichuan section of the Jialing River as the research subject to explore the spatial distribution characteristics of dissolved CH4 and CO2 concentrations and emission fluxes, and the response of the water physical and chemical properties and land use types to greenhouse gas emissions. Surface water samples were collected from the Jialing River in October 2021, and a modified headspace method was used to capture dissolved CH4 and CO2 in the water. Results indicate that human activities dominate the changes in water quality in the Sichuan section of the Jialing River, with urban and agricultural activities being the primary reasons for the accumulation of nitrogen and phosphorus along the river. The concentrations of CH4 and CO2 in the surface water were (16.87±15.55) nmol·L-1 and (836.11±132.68) μmol·L-1, respectively. The emission fluxes of CH4 and CO2 were (68.39±81.26) nmol·m-2·d-1 and (1 596.08±1 291.61) μmol·m-2·d-1, respectively. The concentration and emission fluxes of CH4 and CO2 exhibited significant spatial heterogeneity. Among the different land use types, the river reach dominated by cultivated land received significant amounts of non-point source pollution and terrigenous carbon. The input of these pollutants changed the physical and chemical properties of water bodies, the growth of aquatic plants and phytoplankton, and the microbial activities in the river, and further influenced the production and release of CH4 and CO2. TN, PO43--P, and area proportion of cultivated land are the key factors contributing to greenhouse gas emissions in the Sichuan section of the Jialing River, which indicating that Greenhouse gas emissions are not only influenced by the ecological environment of the river but also by human activities under different land use types.
The Removal of N and P by Terrestrial Vegetable Floating Beds in Eutrophic Waters and the Microbiological Analysis of Water and Root System
ZHOU Jia-lin, DUAN Jing-jing, WANG Ning, LI Ming, CHEN Xiao-feng, XUE Li-hong
2024, 40(1):  107-118.  doi:10.19741/j.issn.1673-4831.2022.1189
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In order to explore the nitrogen (N) and phosphorus (P) removal efficiencies of terrestrial vegetable floating beds in eutrophic waters and their influence on microbial communities and denitrification, 16S rDNA high-throughput sequencing and quantitative PCR (qPCR) techniques were used on water samples to analyze the dynamics of N and P concentrations, microbial communities, and functional genes. The results show high removal efficiencies for total phosphorus (TP) and ammonium (NH4+) by terrestrial vegetable floating beds, with the average TP removal efficiency of treatments groups of Oenanthe javanica, Lactuca sativa and Brassica rapa (57.13%, 46.91%, and 40.86%, respectively) superior to that of the control group (25.46%), and the average NH4+ removal efficiency of treatments groups of Oenanthe javanica and Lactuca sativa (51.30% and 48.16%, respectively) higher than that of the control group (27.23%). Analysis of the dominant bacterial species by 16S rDNA high-throughput sequencing indicated that the root surfaces of different vegetable floating beds were all enriched with Rhodobacter for denitrification, and the root surfaces of Oenanthe javanica and Lactuca sativa were enriched with high amounts of Hydrogenophaga to enhance hydrogen autotrophic denitrification. Higher amounts of Gemmatimonas were found in waters surrounding Brassica rapa and the root surfaces of Oenanthe javanica and Lactuca sativa, which would convert N2O into N2 to achieve complete denitrification. Limnohabitans and Flavobacterium exhibited higher abundance in waters of the control group, which would promote ammonia oxidation and denitrification, respectively. The abundance of denitrification functional genes (nirK, nirS, norB and nosZ) in waters increased during the later period of the experiment, with relatively large copy numbers of waters surrounding the roots of Brassica rapa and the root surfaces of Oenanthe javanica and Lactuca sativa. It indicates that, during the latter period of the experiment, the root surfaces of the vegetable floating beds or the surrounding water accumulated a significant number of denitrification functional genes, leading to an enhanced denitrification process. Our study shows that terrestrial vegetable floating beds have good purifying effects on N and P in waters, and can promote denitrification by adjusting dominant bacterial species on the root surfaces or in the surrounding water.
Study on the Adsorption Mechanism of Sodium Hydroxide Modified Biochar/Attapulgite Composites for Lead and Cadmium
GUO Miao, LI Bei-bei, XU Lin-yue, ZHANG Ya-ping, HE Yue
2024, 40(1):  119-129.  doi:10.19741/j.issn.1673-4831.2022.0851
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A novel rice straw biochar/ attapulgite composite (BA) was prepared by pyrolysis under anoxic conditions with rice straw and attapulgite, which was modified with sodium hydroxide to improve its adsorption performance. Batch adsorption experiments, including adsorption kinetics, isothermal adsorption and change of initial pH, were conducted to investigate the adsorption behavior of composite materials in single and binary pollution systems of Cd and Pb. SEM-EDS, BET, FTIR, XRD, and XPS were used to analyze the adsorption mechanisms of modified composites of Cd and Pb. The results show that the adsorption capacity of sodium hydroxide modified composite (NBA) for Cd2+ and Pb2+ was 117.05 and 274.65 mg·g-1, respectively, and the removal efficiency of NBA was increased by 31.2% and 51.7%, respectively, compared with BA. In the binary metal system, the adsorption capacity of NBA was also significantly better than that of BA. The pseudo-second-order kinetics model and the Langmuir isotherm model could describe the Cd2+ and Pb2+ adsorption processes of the composites better, which proves that the adsorption is mainly a single molecule chemical adsorption process. In addition, competitive adsorption analysis showed that Pb2+ was more easily adsorbed by composite materials than Cd2+ in coexisting solutions. The characterization method determined the adsorption mechanism of NBA for Cd2+ and Pb2+, mainly including the complexation with surface functional groups, precipitation with minerals and π-electron interaction. In conclusion, NBA is a highly potential adsorption material for the treatment of heavy metal pollution in wastewater.
Differences in Lead and Cadmium Accumulation and Translocation in Different Varieties of Zea mays
LIU Qi, WANG Sheng, HE Tao, BAO Li, ZHANG Nai-ming
2024, 40(1):  130-137.  doi:10.19741/j.issn.1673-4831.2022.1008
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This study selected the main maize production area of Yunnan, a region high in concentrated heavy metal contamination, to identify maize varieties displaying low lead (Pb) and cadmium (Cd) accumulation suitable for cultivation. Eighteen maize varieties were selected for field trials to investigate the differences between their characteristics in the same heavy metal-contaminated soil. Cluster analysis was used to examine the Pb and Cd accumulation and transport coefficients according to the seed Pb and Cd content. The results show significant differences between the root biomass, yield, plant height, and Pb and Cd content of the 18 tested maize varieties. Except for Shengyu 607, which exceeded the national food safety standard, the Pb and Cd levels in the other 17 varieties all met the criteria and could be safely used on the Pb- and Cd-contaminated cropland in eastern Yunnan. Among them, Diwo 7, Yunliang 1, and Diwo 2 were suitable for cultivation in this region due to their low Pb and Cd accumulation and high yield capacity.
Development of the Low-temperature Composting Initiating Bacterial Agent and the Efficiency Evaluation
YANG Ming-zhu, XU Huan-huan, GUO Chuan-xu, XIA Yan-wei, MIAO You-zhi, ZHENG Shu-lin, ZHANG Rui-fu
2024, 40(1):  138-146.  doi:10.19741/j.issn.1673-4831.2022.0827
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Regarding the difficult initiation of the composting in low-temperature winter, this study optimized the low-temperature initiating agent, and evaluated the application efficiency of the initiating agent for the manure compost production in an organic fertilizer plant in winter. The low temperature growth characteristics and protease production performance of the strains isolated from the antarctic poles were measured. Pseudomonas marginalis MP-1, Arthrobacter scleromae AS-3 and Arthrobacter oryzae AO-4 were selected for this study. The protease activity of MP-1, AS-3 and AO-4 reached 82.1, 64.3 and 80.3 U·mL-1, respectively, when cultured at 15 ℃ for 24 h, they were mixed based on the ratio of 2∶1∶1 to make the bacterial initiating consortia (IM). The compost extract was made from the raw materials of Chinese medicinal residue, chicken manure and tea meal, and inoculated with the consortia to test their growth with these extracts. The results show that IM could grow to 1.04×1010 cfu·mL-1 in the compost extract of Chinese medicinal residue for 24 h, to 1.41×1010 cfu·mL-1 in chicken manure compost extract and to 3.6×106 cfu·mL-1 in tea meal extract. The results show that compared with the inoculators in commercial compost, IM could effectively promote the rapid starting of chicken manure compost under low temperature in winter. The temperature rising rate of IM treatment was 19.4 ℃·d-1, while that of control group was 15.84 ℃·d-1. The composting of IM reached the high-temperature stage 3 days earlier than that of the control treatment. On the 35th day of composting, the contents of total P and total K in the IM treatment were increased by 2.32 and 4.27 percentage points, respectively, and the seed germination rate (GI) of IM treatment reached 93.3%, which was 10.2 percentage points higher than that of the control group. In conclusion, inoculation of IM can effectively promote the rapid initiation of low-temperature composting, shorten the composting cycle, promote the decomposition of toxic substances, accelerate the innoxious process of low-temperature composting, and improve the efficiency of low-temperature composting in winter.
Delimiting of Ecological Buffer Zone in Hongze Lake Based on Phillips Retention Model
LIU Ding-wu, SHI Zhu-kai, YANG Yang, ZHU Xiao-dong
2024, 40(1):  147-155.  doi:10.19741/j.issn.1673-4831.2022.1243
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Ecological buffer zone (EBZ) of lakes plays substantial role in intercepting pollutants and ecological restoration. In this study, based on the Sentinel-2 satellite data, the boundary of ecological buffer zone of Hongze Lake was delimited by using Phillips detention model targeting at non-point pollutions control. Finally, comparisons were conducted on the environmental performances of un-delimited, fixed-width and non-fixed width buffer zones by applying landscape ecological risk assessment. The results show that: (1) The width of the EBZ of Hongze Lake ranged from 2 to 60 m, accounting for 85.50% of the total. (2) Following the Technical guide for the protection and restoration of ecological buffer zones of rivers and lakes, the lakeshore was divided into six groups including: well-vegetated type, farmland-dominated type, aquaculture-dominated type, village-dominated type, urban-dominated type and estuarine-dominated type. The optimizing width values of EBZ for the aforementioned type of lakeshore with the goal of non-point sources pollution control were 57.62, 34.05, 32.79, 40.18, 38.99, and 22.99 m, respectively. (3) With the construction of a single landcover type, the non-fixed-width EBZ demonstrated a reducing effect on the ecological risk (ER) of Hongze lakeshore, whereas the ER of the fixed-width was estimated to be increased. The key factors affecting environmental performance of EBZ in Hongze Lake are slope and soil conditions. Therefore, it is essential for further implementation of EBZ that local government should pay attention to appropriate topographic adjustment and improvement in soil condition with the priority of delimiting of non-fixed width buffer zones. Meanwhile, ecological risk assessment should be conducted when delimiting fixed width buffer zone.