Mediated by pollenflow,natural hybridization is deemed a crucial factor that propels speciation infloral plants.Despite the fact that the diversity of Epimedium species is concentrated mainly in Southwestern China,the p...Mediated by pollenflow,natural hybridization is deemed a crucial factor that propels speciation infloral plants.Despite the fact that the diversity of Epimedium species is concentrated mainly in Southwestern China,the poten-tial impact of interspecific pollination on natural hybridization has yet to be empirically scrutinized.To explore this,we studied theflowering period and the visitors offlowers in three frequently overlapping Epimedium species at Jinchengshan National Forest Park,located in Nanchong,Sichuan Province.Additionally,we performed a ser-ies of pollination experiments to examine breeding systems and hybrid compatibility.Morphologically,Epime-dium pubescens and Epimedium wushanense are clearly distinct and easily recognizable byflower morphology,while the putative hybrid is morphologically intermediate between them.Our observation revealed that E.pub-escens and E.wushanense had 15 days of overlapping anthesis.Both species are self-incompatible and require pol-linator services for successful reproduction.Although their pollinators differ in quantity and species,Lasioglossum sp.(Hymenoptera:Halictidae)visited all three species.Artificial pollination revealed no breeding barriers among the three species,and the resulting hybrid seeds exhibited fertility.The overlapping time offlowering,commonfloral visitors,and compatibility of hybrids may be important factors contributing to successful interspecific pol-lination and speciation for natural hybrid species of E.pubescens and E.wushanense.Consequently,the role of potential interspecific pollination is crucial for hybrid speciation and the evolutionary dynamics of Epimedium species.展开更多
To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit att...To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit attached green space and main road in the area under administration.The survey results showed that there were 29 species of urban landscape plant diseases,mainly powdery mildew and spot diseases.According to the characteristics of the diseases,the causes and problems of the diseases were analyzed,and the corresponding prevention and control measures were put forward.展开更多
A total of 348 species belonging to 8 phyla and 125 genera were observed in seasonally sampled phytoplankton of tidal rivers from 13 sampling sites around Luoyuan Bay, and all field samplings were carried out in produ...A total of 348 species belonging to 8 phyla and 125 genera were observed in seasonally sampled phytoplankton of tidal rivers from 13 sampling sites around Luoyuan Bay, and all field samplings were carried out in productive period(March/June/August/December) at ebb tide. Bacillariophyta species were the most abundant species, followed by Chlorophyta, Cyanophytes, Euglenophyta, Cryptophyta, Dinophyta, Xanthophyta and Chrysophytas. Seasonal distribution index(SDI) value ranged from 0.63 to 0.86, which meant that species found at those sites in 4 seasons tended to be largely different. Phytoplankton individuals ranged from 5.939×10~4 ind L^(-1) in winter to 75.31×10~4 ind L^(-1) in autumn. Phytoplankton biomass ranged from 0.620 mg L^(-1) in summer to 2.373 mg L^(-1) in autumn. The grey correlation analysis(GCA) showed that the nutrient variables played an important role in the influence on phytoplankton community in every season. The canonical correspondence analysis(CCA) revealed impact of environmental variables on the different species, most of Bacillariophyta species were negative correlation with nutrients(TP and NH_3-N) in the four seasons, Chlorophyta species and Cyanophyta species did not show obvious correlation with environment variables in every season. The combination of GRA analysis and CCA analysis provided a method to quantitatively reveal the correlation between phytoplankton community and environmental variables in water body of tidal rivers at this region.展开更多
To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communit...To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter(73), moderate in autumn(70), but lower in summer(31) and spring(27). The species richness index in autumn(5.92) and winter(4.28) was higher than that in summer(2.83) and spring(1.41).The Shannon-Wiener diversity index was high in autumn(2.82), followed by winter(1.99) and summer(1.92), and low in spring(0.07). The species evenness index in autumn(0.46) and summer(0.39) was higher than that in winter(0.32) and spring(0.02). On the basis of principal component analysis(PCA) and redundancy analysis(RDA), we found that dissolved inorganic nitrogen(DIN) and chemical oxygen demand(COD) in spring, COD in summer, p H in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis(CA) based on key environmental variables.展开更多
Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most re...Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most relevant to predicting soil properties at the catchment scale in semi-arid areas. Thus, this research aims to investigate the ability of multivariate statistical analyses to distinguish which soil properties follow a clear spatial pattern conditioned by specific environmental characteristics in a semi-arid region of Iran. To achieve this goal, we digitized parent materials and landforms by recent orthophotography. Also, we extracted ten topographical attributes and five remote sensing variables from a digital elevation model(DEM) and the Landsat Enhanced Thematic Mapper(ETM), respectively. These factors were contrasted for 334 soil samples(depth of 0–30 cm). Cluster analysis and soil maps reveal that Cluster 1 comprises of limestones, massive limestones and mixed deposits of conglomerates with low soil organic carbon(SOC) and clay contents, and Cluster 2 is composed of soils that originated from quaternary and early quaternary parent materials such as terraces, alluvial fans, lake deposits, and marls or conglomerates that register the highest SOC content and the lowest sand and silt contents. Further, it is confirmed that soils with the highest SOC and clay contents are located in wetlands, lagoons, alluvial fans and piedmonts, while soils with the lowest SOC and clay contents are located in dissected alluvial fans, eroded hills, rock outcrops and steep hills. The results of principal component analysis using the remote sensing data and topographical attributes identify five main components, which explain 73.3% of the total variability of soil properties. Environmental factors such as hillslope morphology and all of the remote sensing variables can largely explain SOC variability, but no significant correlation is found for soil texture and calcium carbonate equivalent contents. Therefore, we conclude that SOC can be considered as the best-predicted soil property in semi-arid regions.展开更多
Embedded ArcGIS Engine can improve development efficiency of environmental information system. The authors designed the structure, functions and database of the Yongjiang River Basin Water Environment Management Infor...Embedded ArcGIS Engine can improve development efficiency of environmental information system. The authors designed the structure, functions and database of the Yongjiang River Basin Water Environment Management Information System (YRBWEMIS) through the integration of ArcGIS Engine software with VC. The spatial data and attribute data in the YRBWEMIS are stored and managed separately. The system functions include display, query, statistics, spatial analysis and thematic mapping for water pollution sources, water quality, water function regionalization and catchments region.展开更多
In 1999, Diexi paleo-dammed lake(2349 m a.s.l.) was discovered around Diexi town along the Minjiang River in Sichuan province. Diexi is located where the eastern edge of the Tibetan Plateau and the Sichuan Basin meet....In 1999, Diexi paleo-dammed lake(2349 m a.s.l.) was discovered around Diexi town along the Minjiang River in Sichuan province. Diexi is located where the eastern edge of the Tibetan Plateau and the Sichuan Basin meet. The dammed lake was formed during the Last Glacial Maximum of the Late Pleistocene(~30,000 years ago) and began to empty about 15,000 years ago. The lacustrine sediments(up to 240 m thick) preserve abundant paleoenvironment information. In this paper, a mass of oxygen isotopes and 14 C dating from drilled cores are analyzed and discussed. The δ18 O curve on the paleo climate from this section is comparable with the coeval paleo climatic curves of ice cores and karsts in China and others. Furthermore, the physical model testing has confirmed that the disturbed zones in the core are caused by strong earthquakes occurred at least 10 times, which implies strong crustal deformation, as an important driving force, affecting climate change. This study provides a new window to observe East Asian monsoon formation, paleoenvironmental evolution and the global climate change.展开更多
The degree and scale of underground space development are growing with the continuous advancement of urbanization in China.The lack of research on the change of the groundwater flow field before and after the developm...The degree and scale of underground space development are growing with the continuous advancement of urbanization in China.The lack of research on the change of the groundwater flow field before and after the development of underground space has led to various problems in the process of underground space development and operation.This paper took the key development zone of the Xiong’an New Area as the study area,and used the Groundwater modeling system software(GMS)to analyse the influence on the groundwater flow field under the point,line,and surface development modes.The main results showed that the underground space development would lead to the expansion and deepening of the cone of depression in the aquifer.The groundwater level on the upstream face of the underground structure would rise,while the water level on the downstream face would drop.The“line”concurrent development has the least impact on the groundwater flow field,and the maximum rise of water level on the upstream side of the underground structure is expected to be approximately 3.05 m.The“surface”development has the greatest impact on the groundwater flow field,and the maximum rise of water level is expected to be 7.17 m.展开更多
Based on the observed data in monitored drainage areas and GIS spatial analysis tools,watershed basic database of Shitoukoumen Reservoir Basin was built.The multivariate analysis and redundancy analysis(RDA) were used...Based on the observed data in monitored drainage areas and GIS spatial analysis tools,watershed basic database of Shitoukoumen Reservoir Basin was built.The multivariate analysis and redundancy analysis(RDA) were used to analyze the spatial and temporal variations of water quality,identify the key environmental factors and their patterns influencing the spatial variation of water quality,and determine the main types and forms of the non-point source(NPS) pollutant export controlled by the key environmental factors.The results show that different patterns of environmental factors lead to great changes in water quality at spatial and seasonal scales.All selected environmental factors explain 64.5% and 68.2% of the spatial variation of water quality over dry season and rainy season,respectively,which shows clear seasonal difference.Over dry season,residential land is the most important environmental factor,which possesses 35.4% of the spatial variation,and drainage area is the second key environmental factor,which possesses 17.0% of spatial variation in the total variance.Over rainy season,slope length and drainage area are the key environmental factors,which possess 29.3% of the spatial variation together.Residential land influences nitrogen export by changing NH4+-N and particulate organic nitrogen(PON) discharge over dry season,and drainage area controls phosphorus export by regulating dissolved phosphorus(DP) drainage over dry season and phosphorus associated particulate(PAP) loss over rainy season,respectively.Although slope length is an important environmental factor,it does not influence NPS pollutant export.It is interesting that soil organic matter,as a minor environmental factor,highly determines phosphorus and nitrogen export by enhancing the DP,PAP and PON loss.展开更多
Objective This paper aims to elucidate the combined toxicity of magnetite nanoparticles/Chromium [MNPs/Cr(Ⅵ)] adducts. Methods The HEK293 cell was exposed to either Cr(Ⅵ) or MNPs, or their adducts MNPs/Cr(Ⅵ). The c...Objective This paper aims to elucidate the combined toxicity of magnetite nanoparticles/Chromium [MNPs/Cr(Ⅵ)] adducts. Methods The HEK293 cell was exposed to either Cr(Ⅵ) or MNPs, or their adducts MNPs/Cr(Ⅵ). The cytotoxicity was evaluated by assessing the cell viability, apoptosis, oxidative stress induction, and cellular uptake. Results The toxicity of formed adducts is significantly reduced when compared to Cr(Ⅵ) anions. We found that the cellular uptake of MNPs/Cr(Ⅵ) adduct was rare, only few particles were endocytosed from the extracellular fluid and not accumulated in the cell nucleus. On the other hand, the Cr(Ⅵ) anions entered cells, generated oxidative stress, induced cell apoptosis, and caused cytotoxicity. Conclusion The results showed minor effects of the nanoadducts on the tested cells and supported that magnetite nanoparticles could be implemented in the wastewater treatment process in which advantageous properties outweigh the risks.展开更多
Photoelectrochemical(PEC) technology has been proved a promising approach to solve the problems of energy shortages and environmental pollution damages.It can convert unlimited solar energy resources into energy forms...Photoelectrochemical(PEC) technology has been proved a promising approach to solve the problems of energy shortages and environmental pollution damages.It can convert unlimited solar energy resources into energy forms needed by mankind.The development of highly efficient photoanodes is a key step in realizing the large-scale practical application of PEC systems.However,the development of PEC photoanodes has been severely hindered by the issues of easy recombination of photo-generated charge carriers,low photon-to-electron conversion efficiency,poor photo-corrosion resistance,and low catalytic activity.Therefore,constructing high-performance and stable photoanodes is an urgent research field to promote the progress of PEC technology.The atomically thin molybdenum disulfide(AT-MoS_(2)) with unique physical and chemical properties has been widely applied in the fabrication of PEC photoanodes.The AT-MoS_(2) based photoanodes have exhibited excellent PEC performance,which providing promising candidates for ideal PEC application.Here,we summarize the fundamental natures of MoS_(2) and present the research efforts in the preparation of AT-MoS_(2) based photoanodes.Strategies for the fabrication of high-efficient AT-MoS_(2) based photoanodes are emphasized to provide guidelines to advance emerging PEC photoanodes.Besides,perspectives for the development of more efficient AT-MoS_(2) based photoanodes are proposed.展开更多
The 21st century shall be a century of accelerated development of tunnel construction in China. But until now, what have been frequently stated in reports about influence of tunnels on environment are basically negati...The 21st century shall be a century of accelerated development of tunnel construction in China. But until now, what have been frequently stated in reports about influence of tunnels on environment are basically negative. In fact, this is not true. Tunnels, especially those extend across sensitive areas do exert some positive functions on improving environment and preventing local slope hazards. These positive effects, being new phenomena, are found and put forward by the authors after a series of careful observations have been carried out and in-depth analysis performed the first time. Meanwhile, it is a positive evaluation that the authors made upon tunnels. Many important phenomena and data are cited as evidence and their causative factors are analyzed in this paper as well.展开更多
In order to research the distribution of thermal field of low temperature discharge from LNG in the ocean, further to formulate reasonable wastewater marine disposal scheme and provide scientific support to the protec...In order to research the distribution of thermal field of low temperature discharge from LNG in the ocean, further to formulate reasonable wastewater marine disposal scheme and provide scientific support to the protection of ocean environment, a two-dimensional hydrodynamic model was used to simulate the tide current field in the radial sand ridge group of shallow sea area of Jiangsu maritime space. This model was based on the tide current characteristics near the LNG project and the seasonal design of the typical hydrological conditions in different seasons. This model was used as the hydrodynamic condition that simulated the transport and diffusion for the heat quantity in the change of time and spatial distribution. Considering the comprehensive heat radiation coefficient of water surface, the 2-D water temperature model was established to predict the spatial distribution and temporal variation of the temperature field in the receiving waters. Finally, results showed that the low temperature drainage less affected in the ocean water environment.展开更多
The interact of construction and circumstance becomes more and more obviously,and research on it is essentially urgent.The way to solve it,first it relies on quantifiable evaluation to the effects done by different co...The interact of construction and circumstance becomes more and more obviously,and research on it is essentially urgent.The way to solve it,first it relies on quantifiable evaluation to the effects done by different construction techniques,then,choose related techniques which cause less damage according to the endurance of circumstance.展开更多
Nutrient release from sediment is considered a significant source for overlying water. Given that nutrient release mechanisms in sediment are complex and difficult to simulate, traditional approaches commonly use assi...Nutrient release from sediment is considered a significant source for overlying water. Given that nutrient release mechanisms in sediment are complex and difficult to simulate, traditional approaches commonly use assigned parameter values to simulate these processes. In this study, a nitrogen flux model was developed and coupled with the water quality model of an urban lake. After parameter sensitivity analyses and model calibration and validation, this model was used to simulate nitrogen exchange at the sediment–water interface in eight scenarios. The results showed that sediment acted as a buffer in the sediment–water system. It could store or release nitrogen at any time, regulate the distribution of nitrogen between sediment and the water column, and provide algae with nitrogen. The most effective way to reduce nitrogen levels in urban lakes within a short time is to reduce external nitrogen loadings. However, sediment release might continue to contribute to the water column until a new balance is achieved. Therefore, effective measures for reducing sediment nitrogen should be developed as supplementary measures. Furthermore, model parameter sensitivity should be individually examined for different research subjects.展开更多
Photocatalytic removal of tetracycline(TC)from the wastewater is of great value in the chemical and environmental engineering field.Here,we introduced a facile one-step method for the synthesis of BiOBr/Bi2WO6 heteroj...Photocatalytic removal of tetracycline(TC)from the wastewater is of great value in the chemical and environmental engineering field.Here,we introduced a facile one-step method for the synthesis of BiOBr/Bi2WO6 heterojunctions by using cheap CTAB as the Br source.We showed the possibility of our method to fine-tune the content of BiOBr in the produced BiOBr/Bi2WO6 by simply changing the dosage of cetyltrimethylammonium bromide(CTAB),providing a platform for the delicate tuning of the visiblelight absorbance ability of the composites.With a suitable heterojunction structure of BiOBr/Bi2WO6-0.2,it exhibited an ultrarapid photocatalytic activity towards TC(20 mgL^(-1)),with a competitive removal efficiency of 88.1%within 60 min and an ultrahigh removal rate of 0.0349 min^(-1).It could also be robustly recycled for at least 5 cycles with slight removal efficiency loss.We demonstrated that this exciting photocatalytic performance was due to the highly decreased recombination of photoinduced electrons and holes on our composites by constructing this heterojunction structure,and the resultingOH andO^(-)_(2)contributed to the effective degradation of TC to CO_(2).展开更多
This study aims to investigate the efiect of the mesoscopic characteristics of mineral powder fillers on the rutting resistance of asphalt mortar.Extraction and sieving tests were used to obtain the buton rock asphalt...This study aims to investigate the efiect of the mesoscopic characteristics of mineral powder fillers on the rutting resistance of asphalt mortar.Extraction and sieving tests were used to obtain the buton rock asphalt(BRA)ash with particle size smaller than 0.075 mm,which is consistent with that of the conventional mineral powder.The mesoscopic characteristics of BRA ash and conventional mineral powder were measured by SEM image analysis and the osmotic free pressure water method.Mesoscopic structure models of structural and free asphalts in mortar were obtained.The 70#matrix asphalt was used to prepare two kinds of asphalt mortar with BRA ash and conventional mineral powders fillers.The rutting factor of the two asphalt mortars was tested by dynamic shear test(DSR).Test results show that the ash extracted from BRA has a similar mesoscopic classification with the conventional mineral powder.Still,its fractal dimensions are larger,indicating the particles in BRA ash have more complex shapes and rougher surfaces,which is beneficial for forming structural asphalt and subsequently increasing the rutting factor(G*/sinδ),i e,improving the rutting resistance of the asphalt mortar.展开更多
Environmental stresses caused by climate change have severely affected agriculture in the present century;Salinity and drought have challenged most forecasts for increased agricultural production in the past few decad...Environmental stresses caused by climate change have severely affected agriculture in the present century;Salinity and drought have challenged most forecasts for increased agricultural production in the past few decades,there-fore,different methods that reduce the effect of these stresses on plants have attracted scientists’attention.The effect of beneficial soil microorganisms on soil health and increasing plants’resistance to stresses is one of the solutions that researchers have paid attention to.This study investigated how Trichoderma species can be affected by the molecular and morphophysiological mechanisms of plants and improve their salt and drought resistance.This study also studied the different Trichoderma species’functions to get a better understanding of how they reduce salt and drought stresses.Furthermore,thefindings of this study provide a clear path for future research to focus on the unknown aspects of Trichoderma species andfind effective ways to boost crop production under environmental stresses.展开更多
Rice is an essential part of the human diet in most parts of the world;On the other hand,the industrialization of societies has led to pollution of the environment,including heavy metal contamination of soil and water...Rice is an essential part of the human diet in most parts of the world;On the other hand,the industrialization of societies has led to pollution of the environment,including heavy metal contamination of soil and water,which negatively affects rice production and quality.Therefore,finding ways to increase the yield and quality of this strategic crop seems essential.Several studies have been conducted in recent decades to find effective and inexpensive solutions to reduce the adverse effects of heavy metals in rice fields.Due to the negative effect of cadmium pollution on rice quality and yield,the current study aimed to investigate cadmium absorption and transfer mechanisms in rice(from absorption by roots to loading in grains),and its effects on rice morphology,physiology,and biochemistry(such as biomass,nutrient absorption,antioxidant defenses).Also,rice’s natural mechanisms for detoxifying cadmium were discussed.This study also intended to identify the absorption and transfer pathways of silicon and selenium in rice,their roles in improving rice structures,and their antagonistic effects on reducing cadmium stress(absorption,transport,and toxicity of cadmium).展开更多
The co-utilization of green manure (GM) and rice straw (RS) in paddy fields has been widely applied as an effective practice in southern China.However,its effects on soil aggregate and soil organic carbon (SOC) stabil...The co-utilization of green manure (GM) and rice straw (RS) in paddy fields has been widely applied as an effective practice in southern China.However,its effects on soil aggregate and soil organic carbon (SOC) stability remain unclear.In the present study,the effect of GM,RS,and co-utilization of GM and RS on particle size distribution of soil aggregates and SOC density fractions were measured in a field experiment.The experiment included six treatments,i.e.,winter fallow (WF) without RS return (Ctrl),WF with 50%RS return (1/2RS),WF with 100%RS return (RS),GM without RS return (GM),GM with 50%RS return (GM1/2RS) and GM with 100%RS return (GMRS).The results showed that the proportion of small macro-aggregates (0.25–2 mm) and the mean weight diameter (MWD) of aggregates in the GMRS treatment was greater (by 18.9 and 3.41%,respectively) than in the RS treatment,while the proportion of silt+clay particles (<0.053 mm) was lower (by 14.4%).The concentration of SOC in microaggregates (0.053–0.25 mm)and silt+clay particles was higher in the GMRS treatment than in GM and RS treatments individually.The concentration and proportion of free light organic carbon (fLOC) in aggregates of various particle sizes and bulk soil was greater in the GMRS treatment than the RS treatment,whereas the concentration and proportion of mineral-associated organic carbon in small macroaggregates,microaggregates,and bulk was lower in the GMRS treatment than in the RS treatment.The proportion of intra-aggregate particulate organic carbon (iPOC) was greater in the GMRS treatment than in GM treatment.The GMRS treatment had strong positive effects on iPOC in small macroaggregates,suggesting that SOC was transferred from fLOC to iPOC.In conclusion,co-utilizing green manure and rice straw cultivated the SOC pool by increasing the concentration of fLOC and improved soil carbon stability by promoting the sequestration of organic carbon in iPOC as a form of physical protection.展开更多
基金This research was supported by the Natural Science Foundation of Sichuan Province(No.2023NSFSC1282)the National General Cultivation Project of China West Normal University(No.19B029)Youth Foundation Specialization of West China Normal University(No.22KB004).
文摘Mediated by pollenflow,natural hybridization is deemed a crucial factor that propels speciation infloral plants.Despite the fact that the diversity of Epimedium species is concentrated mainly in Southwestern China,the poten-tial impact of interspecific pollination on natural hybridization has yet to be empirically scrutinized.To explore this,we studied theflowering period and the visitors offlowers in three frequently overlapping Epimedium species at Jinchengshan National Forest Park,located in Nanchong,Sichuan Province.Additionally,we performed a ser-ies of pollination experiments to examine breeding systems and hybrid compatibility.Morphologically,Epime-dium pubescens and Epimedium wushanense are clearly distinct and easily recognizable byflower morphology,while the putative hybrid is morphologically intermediate between them.Our observation revealed that E.pub-escens and E.wushanense had 15 days of overlapping anthesis.Both species are self-incompatible and require pol-linator services for successful reproduction.Although their pollinators differ in quantity and species,Lasioglossum sp.(Hymenoptera:Halictidae)visited all three species.Artificial pollination revealed no breeding barriers among the three species,and the resulting hybrid seeds exhibited fertility.The overlapping time offlowering,commonfloral visitors,and compatibility of hybrids may be important factors contributing to successful interspecific pol-lination and speciation for natural hybrid species of E.pubescens and E.wushanense.Consequently,the role of potential interspecific pollination is crucial for hybrid speciation and the evolutionary dynamics of Epimedium species.
基金Supported by Youth Project of Natural Science Foundation of Anhui Province(2008085QC135)Postdoctoral Workstation Project of West Anhui University(WXBSH2020003)+4 种基金Key Program of Natural Science Research Project for Anhui Universities(KJ2021A0954)Forestry Carbon Sequestration Self-funded Science and Technology Project of Anhui Province(LJH[2022]267)Subject of Lu'an Forestry Bureau(0045021093)School-level Quality Engineering Project of West Anhui University(wxxy2021017)Provincial Quality Engineering Project of West Anhui University(2022jyxm1765).
文摘To figure out the disease occurrence of landscape plants in the main urban area of Lu'an City,the author investigated the disease occurrence of landscape plants in park green space,residential green space,unit attached green space and main road in the area under administration.The survey results showed that there were 29 species of urban landscape plant diseases,mainly powdery mildew and spot diseases.According to the characteristics of the diseases,the causes and problems of the diseases were analyzed,and the corresponding prevention and control measures were put forward.
基金financially supported by China Shenhua Energy Company Limited
文摘A total of 348 species belonging to 8 phyla and 125 genera were observed in seasonally sampled phytoplankton of tidal rivers from 13 sampling sites around Luoyuan Bay, and all field samplings were carried out in productive period(March/June/August/December) at ebb tide. Bacillariophyta species were the most abundant species, followed by Chlorophyta, Cyanophytes, Euglenophyta, Cryptophyta, Dinophyta, Xanthophyta and Chrysophytas. Seasonal distribution index(SDI) value ranged from 0.63 to 0.86, which meant that species found at those sites in 4 seasons tended to be largely different. Phytoplankton individuals ranged from 5.939×10~4 ind L^(-1) in winter to 75.31×10~4 ind L^(-1) in autumn. Phytoplankton biomass ranged from 0.620 mg L^(-1) in summer to 2.373 mg L^(-1) in autumn. The grey correlation analysis(GCA) showed that the nutrient variables played an important role in the influence on phytoplankton community in every season. The canonical correspondence analysis(CCA) revealed impact of environmental variables on the different species, most of Bacillariophyta species were negative correlation with nutrients(TP and NH_3-N) in the four seasons, Chlorophyta species and Cyanophyta species did not show obvious correlation with environment variables in every season. The combination of GRA analysis and CCA analysis provided a method to quantitatively reveal the correlation between phytoplankton community and environmental variables in water body of tidal rivers at this region.
基金The Special Project of Science and Technology Fundamental Work from the Ministry of Science and Technology of China under contract No.2012FY112500the National Natural Science Foundation of China under contract Nos 41206111 and 41206112
文摘To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter(73), moderate in autumn(70), but lower in summer(31) and spring(27). The species richness index in autumn(5.92) and winter(4.28) was higher than that in summer(2.83) and spring(1.41).The Shannon-Wiener diversity index was high in autumn(2.82), followed by winter(1.99) and summer(1.92), and low in spring(0.07). The species evenness index in autumn(0.46) and summer(0.39) was higher than that in winter(0.32) and spring(0.02). On the basis of principal component analysis(PCA) and redundancy analysis(RDA), we found that dissolved inorganic nitrogen(DIN) and chemical oxygen demand(COD) in spring, COD in summer, p H in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis(CA) based on key environmental variables.
基金financial support of Isfahan University of Technology (IUT) for this research
文摘Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most relevant to predicting soil properties at the catchment scale in semi-arid areas. Thus, this research aims to investigate the ability of multivariate statistical analyses to distinguish which soil properties follow a clear spatial pattern conditioned by specific environmental characteristics in a semi-arid region of Iran. To achieve this goal, we digitized parent materials and landforms by recent orthophotography. Also, we extracted ten topographical attributes and five remote sensing variables from a digital elevation model(DEM) and the Landsat Enhanced Thematic Mapper(ETM), respectively. These factors were contrasted for 334 soil samples(depth of 0–30 cm). Cluster analysis and soil maps reveal that Cluster 1 comprises of limestones, massive limestones and mixed deposits of conglomerates with low soil organic carbon(SOC) and clay contents, and Cluster 2 is composed of soils that originated from quaternary and early quaternary parent materials such as terraces, alluvial fans, lake deposits, and marls or conglomerates that register the highest SOC content and the lowest sand and silt contents. Further, it is confirmed that soils with the highest SOC and clay contents are located in wetlands, lagoons, alluvial fans and piedmonts, while soils with the lowest SOC and clay contents are located in dissected alluvial fans, eroded hills, rock outcrops and steep hills. The results of principal component analysis using the remote sensing data and topographical attributes identify five main components, which explain 73.3% of the total variability of soil properties. Environmental factors such as hillslope morphology and all of the remote sensing variables can largely explain SOC variability, but no significant correlation is found for soil texture and calcium carbonate equivalent contents. Therefore, we conclude that SOC can be considered as the best-predicted soil property in semi-arid regions.
文摘Embedded ArcGIS Engine can improve development efficiency of environmental information system. The authors designed the structure, functions and database of the Yongjiang River Basin Water Environment Management Information System (YRBWEMIS) through the integration of ArcGIS Engine software with VC. The spatial data and attribute data in the YRBWEMIS are stored and managed separately. The system functions include display, query, statistics, spatial analysis and thematic mapping for water pollution sources, water quality, water function regionalization and catchments region.
基金financially supported by the China National Nature Science Foundation(No.41072230,No.41572308,No.41977226)the State Key Laboratory of Geo-hazard Prevention&Geo-environment Protection(No.SKLGP2012Z008,No.SKLGP2016Z015)
文摘In 1999, Diexi paleo-dammed lake(2349 m a.s.l.) was discovered around Diexi town along the Minjiang River in Sichuan province. Diexi is located where the eastern edge of the Tibetan Plateau and the Sichuan Basin meet. The dammed lake was formed during the Last Glacial Maximum of the Late Pleistocene(~30,000 years ago) and began to empty about 15,000 years ago. The lacustrine sediments(up to 240 m thick) preserve abundant paleoenvironment information. In this paper, a mass of oxygen isotopes and 14 C dating from drilled cores are analyzed and discussed. The δ18 O curve on the paleo climate from this section is comparable with the coeval paleo climatic curves of ice cores and karsts in China and others. Furthermore, the physical model testing has confirmed that the disturbed zones in the core are caused by strong earthquakes occurred at least 10 times, which implies strong crustal deformation, as an important driving force, affecting climate change. This study provides a new window to observe East Asian monsoon formation, paleoenvironmental evolution and the global climate change.
基金the Evaluation of soil and water quality and engineering geological survey in Xiong’an New Area Program of China(Grant No.DD20189122)National Natural Science Foundation of China(Grant No.42102294).
文摘The degree and scale of underground space development are growing with the continuous advancement of urbanization in China.The lack of research on the change of the groundwater flow field before and after the development of underground space has led to various problems in the process of underground space development and operation.This paper took the key development zone of the Xiong’an New Area as the study area,and used the Groundwater modeling system software(GMS)to analyse the influence on the groundwater flow field under the point,line,and surface development modes.The main results showed that the underground space development would lead to the expansion and deepening of the cone of depression in the aquifer.The groundwater level on the upstream face of the underground structure would rise,while the water level on the downstream face would drop.The“line”concurrent development has the least impact on the groundwater flow field,and the maximum rise of water level on the upstream side of the underground structure is expected to be approximately 3.05 m.The“surface”development has the greatest impact on the groundwater flow field,and the maximum rise of water level is expected to be 7.17 m.
基金Under the auspices of Cooperation Program of Chinese Academy of Sciences and Jilin Province (No 2006SYHZ0025)Knowledge Innovation Programs of Chinese Academy of Sciences (No KZCX2-YW-126,KZCX2-YW-Q06-2)
文摘Based on the observed data in monitored drainage areas and GIS spatial analysis tools,watershed basic database of Shitoukoumen Reservoir Basin was built.The multivariate analysis and redundancy analysis(RDA) were used to analyze the spatial and temporal variations of water quality,identify the key environmental factors and their patterns influencing the spatial variation of water quality,and determine the main types and forms of the non-point source(NPS) pollutant export controlled by the key environmental factors.The results show that different patterns of environmental factors lead to great changes in water quality at spatial and seasonal scales.All selected environmental factors explain 64.5% and 68.2% of the spatial variation of water quality over dry season and rainy season,respectively,which shows clear seasonal difference.Over dry season,residential land is the most important environmental factor,which possesses 35.4% of the spatial variation,and drainage area is the second key environmental factor,which possesses 17.0% of spatial variation in the total variance.Over rainy season,slope length and drainage area are the key environmental factors,which possess 29.3% of the spatial variation together.Residential land influences nitrogen export by changing NH4+-N and particulate organic nitrogen(PON) discharge over dry season,and drainage area controls phosphorus export by regulating dissolved phosphorus(DP) drainage over dry season and phosphorus associated particulate(PAP) loss over rainy season,respectively.Although slope length is an important environmental factor,it does not influence NPS pollutant export.It is interesting that soil organic matter,as a minor environmental factor,highly determines phosphorus and nitrogen export by enhancing the DP,PAP and PON loss.
文摘Objective This paper aims to elucidate the combined toxicity of magnetite nanoparticles/Chromium [MNPs/Cr(Ⅵ)] adducts. Methods The HEK293 cell was exposed to either Cr(Ⅵ) or MNPs, or their adducts MNPs/Cr(Ⅵ). The cytotoxicity was evaluated by assessing the cell viability, apoptosis, oxidative stress induction, and cellular uptake. Results The toxicity of formed adducts is significantly reduced when compared to Cr(Ⅵ) anions. We found that the cellular uptake of MNPs/Cr(Ⅵ) adduct was rare, only few particles were endocytosed from the extracellular fluid and not accumulated in the cell nucleus. On the other hand, the Cr(Ⅵ) anions entered cells, generated oxidative stress, induced cell apoptosis, and caused cytotoxicity. Conclusion The results showed minor effects of the nanoadducts on the tested cells and supported that magnetite nanoparticles could be implemented in the wastewater treatment process in which advantageous properties outweigh the risks.
基金financially supported by the Science and Technology Plans of Tianjin (18PTZWHZ00180)Major National Science and Technology Projects (2017ZX07106001)Tianjin Development Program for Innovation and Entrepreneurship。
文摘Photoelectrochemical(PEC) technology has been proved a promising approach to solve the problems of energy shortages and environmental pollution damages.It can convert unlimited solar energy resources into energy forms needed by mankind.The development of highly efficient photoanodes is a key step in realizing the large-scale practical application of PEC systems.However,the development of PEC photoanodes has been severely hindered by the issues of easy recombination of photo-generated charge carriers,low photon-to-electron conversion efficiency,poor photo-corrosion resistance,and low catalytic activity.Therefore,constructing high-performance and stable photoanodes is an urgent research field to promote the progress of PEC technology.The atomically thin molybdenum disulfide(AT-MoS_(2)) with unique physical and chemical properties has been widely applied in the fabrication of PEC photoanodes.The AT-MoS_(2) based photoanodes have exhibited excellent PEC performance,which providing promising candidates for ideal PEC application.Here,we summarize the fundamental natures of MoS_(2) and present the research efforts in the preparation of AT-MoS_(2) based photoanodes.Strategies for the fabrication of high-efficient AT-MoS_(2) based photoanodes are emphasized to provide guidelines to advance emerging PEC photoanodes.Besides,perspectives for the development of more efficient AT-MoS_(2) based photoanodes are proposed.
文摘The 21st century shall be a century of accelerated development of tunnel construction in China. But until now, what have been frequently stated in reports about influence of tunnels on environment are basically negative. In fact, this is not true. Tunnels, especially those extend across sensitive areas do exert some positive functions on improving environment and preventing local slope hazards. These positive effects, being new phenomena, are found and put forward by the authors after a series of careful observations have been carried out and in-depth analysis performed the first time. Meanwhile, it is a positive evaluation that the authors made upon tunnels. Many important phenomena and data are cited as evidence and their causative factors are analyzed in this paper as well.
文摘In order to research the distribution of thermal field of low temperature discharge from LNG in the ocean, further to formulate reasonable wastewater marine disposal scheme and provide scientific support to the protection of ocean environment, a two-dimensional hydrodynamic model was used to simulate the tide current field in the radial sand ridge group of shallow sea area of Jiangsu maritime space. This model was based on the tide current characteristics near the LNG project and the seasonal design of the typical hydrological conditions in different seasons. This model was used as the hydrodynamic condition that simulated the transport and diffusion for the heat quantity in the change of time and spatial distribution. Considering the comprehensive heat radiation coefficient of water surface, the 2-D water temperature model was established to predict the spatial distribution and temporal variation of the temperature field in the receiving waters. Finally, results showed that the low temperature drainage less affected in the ocean water environment.
文摘The interact of construction and circumstance becomes more and more obviously,and research on it is essentially urgent.The way to solve it,first it relies on quantifiable evaluation to the effects done by different construction techniques,then,choose related techniques which cause less damage according to the endurance of circumstance.
基金supported by the Funds of the Nanjing Institute of Technology (Grants No. JCYJ201619 and ZKJ201804).
文摘Nutrient release from sediment is considered a significant source for overlying water. Given that nutrient release mechanisms in sediment are complex and difficult to simulate, traditional approaches commonly use assigned parameter values to simulate these processes. In this study, a nitrogen flux model was developed and coupled with the water quality model of an urban lake. After parameter sensitivity analyses and model calibration and validation, this model was used to simulate nitrogen exchange at the sediment–water interface in eight scenarios. The results showed that sediment acted as a buffer in the sediment–water system. It could store or release nitrogen at any time, regulate the distribution of nitrogen between sediment and the water column, and provide algae with nitrogen. The most effective way to reduce nitrogen levels in urban lakes within a short time is to reduce external nitrogen loadings. However, sediment release might continue to contribute to the water column until a new balance is achieved. Therefore, effective measures for reducing sediment nitrogen should be developed as supplementary measures. Furthermore, model parameter sensitivity should be individually examined for different research subjects.
基金the National Natural Science Foundation of China(Grant No.22108040 and 21878054)the Natural Science Foundation of Fujian Province(2020J05130)+1 种基金Science and Technology Project of Fujian Educational Committee(JAT190051)Research Project of Ningde Normal University(2019T03).
文摘Photocatalytic removal of tetracycline(TC)from the wastewater is of great value in the chemical and environmental engineering field.Here,we introduced a facile one-step method for the synthesis of BiOBr/Bi2WO6 heterojunctions by using cheap CTAB as the Br source.We showed the possibility of our method to fine-tune the content of BiOBr in the produced BiOBr/Bi2WO6 by simply changing the dosage of cetyltrimethylammonium bromide(CTAB),providing a platform for the delicate tuning of the visiblelight absorbance ability of the composites.With a suitable heterojunction structure of BiOBr/Bi2WO6-0.2,it exhibited an ultrarapid photocatalytic activity towards TC(20 mgL^(-1)),with a competitive removal efficiency of 88.1%within 60 min and an ultrahigh removal rate of 0.0349 min^(-1).It could also be robustly recycled for at least 5 cycles with slight removal efficiency loss.We demonstrated that this exciting photocatalytic performance was due to the highly decreased recombination of photoinduced electrons and holes on our composites by constructing this heterojunction structure,and the resultingOH andO^(-)_(2)contributed to the effective degradation of TC to CO_(2).
基金Funded by the National Natural Science Foundation of China(No.51978088)。
文摘This study aims to investigate the efiect of the mesoscopic characteristics of mineral powder fillers on the rutting resistance of asphalt mortar.Extraction and sieving tests were used to obtain the buton rock asphalt(BRA)ash with particle size smaller than 0.075 mm,which is consistent with that of the conventional mineral powder.The mesoscopic characteristics of BRA ash and conventional mineral powder were measured by SEM image analysis and the osmotic free pressure water method.Mesoscopic structure models of structural and free asphalts in mortar were obtained.The 70#matrix asphalt was used to prepare two kinds of asphalt mortar with BRA ash and conventional mineral powders fillers.The rutting factor of the two asphalt mortars was tested by dynamic shear test(DSR).Test results show that the ash extracted from BRA has a similar mesoscopic classification with the conventional mineral powder.Still,its fractal dimensions are larger,indicating the particles in BRA ash have more complex shapes and rougher surfaces,which is beneficial for forming structural asphalt and subsequently increasing the rutting factor(G*/sinδ),i e,improving the rutting resistance of the asphalt mortar.
基金supported by the Anhui Province Large-Scale Online Open Course(MOOC)Demonstration Project(2018mooc428)the Quality Engineering Project of Suzhou University:College of Geographic Information and Energy Agriculture Modern Industry(szxy2021cyxy06)+1 种基金the Key Project of Quality Engineering in Anhui Province(2021jyxm1499)the Scientific Research Platform Project of Suzhou University:Research Center of Non-Point Source Pollution Control and Ecological Remediation(2021XJPT11).
文摘Environmental stresses caused by climate change have severely affected agriculture in the present century;Salinity and drought have challenged most forecasts for increased agricultural production in the past few decades,there-fore,different methods that reduce the effect of these stresses on plants have attracted scientists’attention.The effect of beneficial soil microorganisms on soil health and increasing plants’resistance to stresses is one of the solutions that researchers have paid attention to.This study investigated how Trichoderma species can be affected by the molecular and morphophysiological mechanisms of plants and improve their salt and drought resistance.This study also studied the different Trichoderma species’functions to get a better understanding of how they reduce salt and drought stresses.Furthermore,thefindings of this study provide a clear path for future research to focus on the unknown aspects of Trichoderma species andfind effective ways to boost crop production under environmental stresses.
基金This work was supported by the Anhui Province Large-Scale Online Open Course(MOOC)Demonstration Project(2018mooc428)the Quality Engineering Project of Suzhou University:College of Geographic Information and Energy Agriculture Modern Industry(szxy2021cyxy06)+1 种基金the Key Project of Quality Engineering in Anhui Province(2021jyxm1499)the Scientific Research Platform Project of Suzhou University:Research Center of Non-Point Source Pollution Control and Ecological Remediation(2021XJPT11).
文摘Rice is an essential part of the human diet in most parts of the world;On the other hand,the industrialization of societies has led to pollution of the environment,including heavy metal contamination of soil and water,which negatively affects rice production and quality.Therefore,finding ways to increase the yield and quality of this strategic crop seems essential.Several studies have been conducted in recent decades to find effective and inexpensive solutions to reduce the adverse effects of heavy metals in rice fields.Due to the negative effect of cadmium pollution on rice quality and yield,the current study aimed to investigate cadmium absorption and transfer mechanisms in rice(from absorption by roots to loading in grains),and its effects on rice morphology,physiology,and biochemistry(such as biomass,nutrient absorption,antioxidant defenses).Also,rice’s natural mechanisms for detoxifying cadmium were discussed.This study also intended to identify the absorption and transfer pathways of silicon and selenium in rice,their roles in improving rice structures,and their antagonistic effects on reducing cadmium stress(absorption,transport,and toxicity of cadmium).
基金funded by the National Key Research and Development Program of China (2021YFD1700200)the earmarked fund for China Agriculture Reserch System(CARS-22)the Natural Science Foundation of Jiangsu Province,China (BK20200112)。
文摘The co-utilization of green manure (GM) and rice straw (RS) in paddy fields has been widely applied as an effective practice in southern China.However,its effects on soil aggregate and soil organic carbon (SOC) stability remain unclear.In the present study,the effect of GM,RS,and co-utilization of GM and RS on particle size distribution of soil aggregates and SOC density fractions were measured in a field experiment.The experiment included six treatments,i.e.,winter fallow (WF) without RS return (Ctrl),WF with 50%RS return (1/2RS),WF with 100%RS return (RS),GM without RS return (GM),GM with 50%RS return (GM1/2RS) and GM with 100%RS return (GMRS).The results showed that the proportion of small macro-aggregates (0.25–2 mm) and the mean weight diameter (MWD) of aggregates in the GMRS treatment was greater (by 18.9 and 3.41%,respectively) than in the RS treatment,while the proportion of silt+clay particles (<0.053 mm) was lower (by 14.4%).The concentration of SOC in microaggregates (0.053–0.25 mm)and silt+clay particles was higher in the GMRS treatment than in GM and RS treatments individually.The concentration and proportion of free light organic carbon (fLOC) in aggregates of various particle sizes and bulk soil was greater in the GMRS treatment than the RS treatment,whereas the concentration and proportion of mineral-associated organic carbon in small macroaggregates,microaggregates,and bulk was lower in the GMRS treatment than in the RS treatment.The proportion of intra-aggregate particulate organic carbon (iPOC) was greater in the GMRS treatment than in GM treatment.The GMRS treatment had strong positive effects on iPOC in small macroaggregates,suggesting that SOC was transferred from fLOC to iPOC.In conclusion,co-utilizing green manure and rice straw cultivated the SOC pool by increasing the concentration of fLOC and improved soil carbon stability by promoting the sequestration of organic carbon in iPOC as a form of physical protection.
