Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and en...Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences.展开更多
Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have no...Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.展开更多
[Objectives]This study was conducted to provide good basic research data for Cunninghamia lanceolata plantations in southern Anhui,so as to improve local ecological,economic and social benefits.[Methods]A 22-year-old ...[Objectives]This study was conducted to provide good basic research data for Cunninghamia lanceolata plantations in southern Anhui,so as to improve local ecological,economic and social benefits.[Methods]A 22-year-old near-mature C.lanceolata plantation in Lingnan Forest Farm,Xiuning County,Huangshan City,Anhui Province was investigated and analyzed by sample plot survey.[Results]The average DBH value of the C.lanceolata plantation at the lower slope was the largest,24.7%and 19.2%higher than those at the upper and middle slopes,respectively.The average single plant wood volume at the lower slope was 47.6%and 49.1%higher than those in the upper and middle slopes,respectively.However,the average tree heights at various slope positions showed little difference.Meanwhile,all the indexes showed the phenomenon of semi-shady slope>sunny slope>shady slope under different slope directions.Among them,the effect of slope position on DBH was extremely significant,but the effect of slope direction on DBH was not significant,and slope position,slope direction and the interaction of slope direction and slope position had no significant effects on the tree height of the C.lanceolata plantation.In addition,slope direction and slope position had extremely significant effects on single plant wood volume.From the overall growth situation of the C.lanceolata plantation in Lingnan Forest Farm,the slope position factor had greater effects on various indexes of forest growth than the slope direction factor,mainly manifested in that the lower slope was better than the middle slope,and the middle slope position was better than the upper slope,while although slope direction had some effect on the growth of the C.lanceolata plantation,the influence degree was not as significant as that of slope position.[Conclusions]This study provides some reference for the adjustment and optimization,development and renewal of C.lanceolata plantation structure in the later period in this area,as well as some data support for other theoretical research on economic forests.展开更多
The continuous progress of urbanization has driven the continuous development and innovation of landscape planning and design.Focused on the important design method of modern construction art,this study analyzed its c...The continuous progress of urbanization has driven the continuous development and innovation of landscape planning and design.Focused on the important design method of modern construction art,this study analyzed its concepts and characteristics,and made deep exploration to its application in landscape planning and design.The results indicated that modern construction art had a significant impact on landscape spatial planning and layout,spatial design forms,and spatial ornaments.The use of modern construction art concepts could make landscape design more scientific,artistic,and humane,creating higher quality leisure and entertainment venues for audiences.展开更多
Many anuran species exhibit striking color and/or pattern polymorphisms. We sampled 599 adult rice frogs, Fejervarya multistriata, from a rice paddy in the periphery of the Lingnan Nature Reserve （Huangshan, Anhui）....Many anuran species exhibit striking color and/or pattern polymorphisms. We sampled 599 adult rice frogs, Fejervarya multistriata, from a rice paddy in the periphery of the Lingnan Nature Reserve （Huangshan, Anhui）. We recognized ten morphs based on three relatively stable and distinct morphological characters： dorsal ground color （green or gray）, middorsal stripe （absence, wide, or narrow）, occipital rusty spot （absence or presence）. The grey individuals are more common and larger than the green individuals （frequency 88.1 vs. 11.9%, respectively） and （SVL 39.4-36.6 vs. 35.7-34.6 mm, respectively）. There is a higher proportion of individuals with a middorsal stripe （59.7%） while absence of the occipital rusty spot is more common in the population （82.3%）. We expect additional studies in different habitat types would help build our understanding of the relationship between color polymorphism and habitat, geography, and climate.展开更多
Six main mitochondrial DNA （mtDNA） lineages have been described in minnow （Zacco platypus） samples obtained from northern, western and southern China Perdices et al. （2004） predicted that further sampling of oth...Six main mitochondrial DNA （mtDNA） lineages have been described in minnow （Zacco platypus） samples obtained from northern, western and southern China Perdices et al. （2004） predicted that further sampling of other tributaries might discover more lineages of this species. In this study, we collected 26 Zacco platypus individuals in the Huangshan area of eastern China and determined the cytochrome b （cytb） sequence variations. Combined with reported data in GenBank, we identified ten matrilines （Zacco A-J） in a total of 169 samples, with relatively high molecular divergence found among them. The Huangshan population had the greatest genetic variation among all sampled regions and hosted six of the ten matrilines. Our results highlight the significance of the Huangshan area for the conservation of Zacco platypus.展开更多
With the increasingly prominent problems of ecology, environment and resources in China, green economy development is becoming more and more urgent. Innovation has become the key driving force of economic development....With the increasingly prominent problems of ecology, environment and resources in China, green economy development is becoming more and more urgent. Innovation has become the key driving force of economic development. Economic development of Huangshan City should take the road of "green development " and combine economic development with ecological protection. This paper designs the measurement index of innovation and green economic development, and makes an empirical analysis based on the data of innovation and green economic development in Huangshan City from 2005 to 2016. It is concluded that the index of innovation and green economic development in Huangshan City shows an increasing trend. Innovation has a positive role in promoting green economic development in Huangshan City. Therefore, Huangshan City should strengthen regional innovation management, create regional innovation environment, strengthen cooperation between industry, University and research, increase support for green innovation, promote technological innovation of recycling, and promote the construction of circular economy.展开更多
Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selectio...Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests.展开更多
[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis...[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis.展开更多
With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online cour...With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online courses,digital platforms,and value co-creation have brought new opportunities and challenges to the content,mode,and mechanism of innovation and entrepreneurship education.This paper discusses the content and new opportunities of digital entrepreneurship,analyzes the differences between traditional entrepreneurship and digital entrepreneurship,and puts forward the strategy path of entrepreneurship education under the digital economy.展开更多
Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in ...Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors（BCFs） of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots （0.58-2.28）. BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L.展开更多
Phytoremediation has been used as an emerging technology for remediation of soil contamination with polycyclic aromatic hydrocarbons(PAHs),ubiquitous persistent environmental pollutants derived from natural and anthro...Phytoremediation has been used as an emerging technology for remediation of soil contamination with polycyclic aromatic hydrocarbons(PAHs),ubiquitous persistent environmental pollutants derived from natural and anthropogenic processes,in the last decade.In this study,a pot experiment was conducted to investigate the potential of phytoremediation of pyrene from spiked soils planted with white clover(Trifolium repens)in the greenhouse with a series of pyrene concentrations ranging from 4.22 to 365.38 mg kg-1.The results showed that growth of white clover on pyrenecontaminated soils was not affected.The removal of pyrene from the spiked soils planted with white clover was obviously higher than that from the unplanted soils.At the end of the experiment(60 d),the average removal ratio of pyrene in the spiked soils with white clover was 77%,which was 31%and 57%higher than those of the controls with or without micobes, respectively.Both roots and shoots of white clover took up pyrene from the spiked soils and pyrene uptake increased with the soil pyrene concentration.However,the plant-enhanced dissipation of soil pyrene may be the result of plant-promoted microbial degradation and direct uptake and accumulation of pyrene by white clover were only a small part of the pyrene dissipation.Bioconcentration factors of pyrene(BCFs,ratio of pyrene,on a dry weight basis,in the plant to that in the soil)tended to decrease with increase in the residual soil pyrene concentration.Therefore,removal of pyrene in the contaminated soils was feasible using white clove.展开更多
Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh cond...Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh conditions.Development of durable and high separation performance membranes with lower fabrication and operation cost are highly demanded for industrial applications. Zeolite T membrane possesses good acid-resistance with excellent hydrophilic properties as compared to NaA zeolite membrane and can be extended to industrial organic dehydrations under an acidic environment. In the present review the research advances in development of zeolite T membranes for the dehydration of organic mixtures in acidic conditions are summarized. Especially the low temperature synthesis, and epitaxial growth of the zeolite membrane with high performance are well addressed, besides emphasis is particularly placed on ensemble synthesis of hollow fiber zeolite T membrane module and its future prospects for industrial separations.展开更多
The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes （2 females, 1 male） were sampled in ...The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes （2 females, 1 male） were sampled in Shangri-La, northern Yunnan, China, thus expanding their known distribution region towards the southeast. This site is the southeastern-most corner of the Tibetan Plateau and the southernmost tip of the Hengduan Mountains （Mts.）. Phylogenetic analysis of mitochondrial （mt） and nuclear （n） DNA segments suggested that the three specimens belong to the genus ofThermophis. Morphologically, the new species is more similar toT. zhaoermii. However, it is distinguished fromT.zhaoermiiin the number of maxillary teeth （15）, distance between the two eyes/head width, rostral width/height, mental width/height, in one character limited to female： head width/length, and in four characters restricted to male： occurrence of the reduction from 10 to 8 （8 to 6, 6 to 4） scales in each dorsal row on the tail. There are differences in morphology, genetics （mtDNA, nDNA）, and geography between the putative new species andT.zhaoermii,the new species meets our proposed eclectic and feasible ＂four-differences＂ rule.展开更多
The hot deformation characteristics of as-forged Ti−3.5Al−5Mo−6V−3Cr−2Sn−0.5Fe−0.1B−0.1C alloy within a temperature range from 750 to 910℃and a strain rate range from 0.001 to 1 s^(-1) were investigated by hot compre...The hot deformation characteristics of as-forged Ti−3.5Al−5Mo−6V−3Cr−2Sn−0.5Fe−0.1B−0.1C alloy within a temperature range from 750 to 910℃and a strain rate range from 0.001 to 1 s^(-1) were investigated by hot compression tests.The stress−strain curves show that the flow stress decreases with the increase of temperature and the decrease of strain rate.The microstructure is sensitive to deformation parameters.The dynamic recrystallization(DRX)grains appear while the temperature reaches 790℃at a constant strain rate of 0.001 s^(-1) and strain rate is not higher than 0.1 s^(-1) at a constant temperature of 910℃.The work-hardening rateθis calculated and it is found that DRX prefers to happen at high temperature and low strain rate.The constitutive equation and processing map were obtained.The average activation energy of the alloy is 242.78 kJ/mol and there are few unstable regions on the processing map,which indicates excellent hot workability.At the strain rate of 0.1 s^(-1),the stress−strain curves show an abnormal shape where there are two stress peaks simultaneously.This can be attributed to the alternation of hardening effect,which results from the continuous dynamic recrystallization(CDRX)and the rotation of DRX grains,and dynamic softening mechanism.展开更多
The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Si...The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Sichuan Province,China.Species identity was difficult to delimit morphologically because the specimens were juveniles and partially damaged.Subsequently,a molecular phylogenetic approach was used.Portions of three mitochondrial genes(cyt b,ND4 and 12S rRNA) were sequenced and analyzed.The results showed that they were sister to the genus Elaphe.Very little genetic variation was found among the three samples.The minimum genetic distances between these samples and those within Elaphe were greater than any currently recognized species within the genus.We conclude that this likely represents a new species within the genus Elaphe.Adult specimens and a morphologic description are needed for further study.展开更多
This paper mainly covers a method for preparing a highly alkaline magnesium linoleate solution with a total base number(TBN) value of 328 mg KOH/g using linoleic acid as the biodegradable raw material, which can subst...This paper mainly covers a method for preparing a highly alkaline magnesium linoleate solution with a total base number(TBN) value of 328 mg KOH/g using linoleic acid as the biodegradable raw material, which can substitute for traditional lubricant detergents as an environmentally friendly detergent. Reaction conditions, including the molar ratio of magnesium oxide to linoleic acid, the molar ratio of methanol to magnesium oxide, the carbonation temperature, the molar ratio of water to magnesium oxide, the flow rate of CO2 gas and the duration for injection of CO2 to magnesium oxide system, were optimized.展开更多
One juvenile and one adult female wolf snake（Colubridae： Lycodon） were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon ...One juvenile and one adult female wolf snake（Colubridae： Lycodon） were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon liuchengchaoi based on external morphology and molecular data. This is a new reptile record in Anhui Province. In our laboratory, four eggs were laid and three neonates were hatched successfully. This is the first record of the laying and incubation of L. liuchengchaoi eggs. The five specimens were deposited at the Museum of Huangshan University（HUM20140001） and Guangdong Entomological Institute（HB-lcfsp12613, HB-lcfsp-ch1~3）.展开更多
In computer vision fields,3D object recognition is one of the most important tasks for many real-world applications.Three-dimensional convolutional neural networks(CNNs)have demonstrated their advantages in 3D object ...In computer vision fields,3D object recognition is one of the most important tasks for many real-world applications.Three-dimensional convolutional neural networks(CNNs)have demonstrated their advantages in 3D object recognition.In this paper,we propose to use the principal curvature directions of 3D objects(using a CAD model)to represent the geometric features as inputs for the 3D CNN.Our framework,namely CurveNet,learns perceptually relevant salient features and predicts object class labels.Curvature directions incorporate complex surface information of a 3D object,which helps our framework to produce more precise and discriminative features for object recognition.Multitask learning is inspired by sharing features between two related tasks,where we consider pose classification as an auxiliary task to enable our CurveNet to better generalize object label classification.Experimental results show that our proposed framework using curvature vectors performs better than voxels as an input for 3D object classification.We further improved the performance of CurveNet by combining two networks with both curvature direction and voxels of a 3D object as the inputs.A Cross-Stitch module was adopted to learn effective shared features across multiple representations.We evaluated our methods using three publicly available datasets and achieved competitive performance in the 3D object recognition task.展开更多
A mixture of fault gouge and rubble taken out from a fault zone is used to prepare a S-RM(Soil-Rock Mixture)sample with rock block proportions of 20%,30%,40%,50%,60%and 70%,respectively.A GDS triaxial test system is u...A mixture of fault gouge and rubble taken out from a fault zone is used to prepare a S-RM(Soil-Rock Mixture)sample with rock block proportions of 20%,30%,40%,50%,60%and 70%,respectively.A GDS triaxial test system is used accordingly to measure the seepage characteristics of such samples under different loading and unloading confining pressures in order to determine the variation law of the permeability coefficient.The test results show that:(1)The permeability coefficient of the S-RM samples decreases as the pressure increases,and the decrease rate of this coefficient in the initial stage of confining pressure loading is obviously higher than in the semi-late period;(2)The permeability coefficient at different confining pressure levels presents a common trend as the rock block proportion is increased,i.e.,it decreases first then it increases(the permeability coefficient of the sample with rock block proportion 40%being the smallest,70%the largest);(3)In the stage of confining pressure unloading,the recovery degree of the permeability coefficient grows with the increase of rock block proportion(the recovery rate of S-RM sample with rock block proportion 70%reaches 50.2%);(4)In the stage of confining pressure loading and unloading,the sensitivity of the permeability coefficient to the rock block proportion displays the inverse“Z”variation rule(when rock block proportion reaches 60%,the sensitivity is highest);(5)In the stage of confining pressure loading,the relationship between the permeability coefficient and confining pressure can be described by an exponential relationship.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 32100400)Huangshan University Startup Project of Scientific Research (2020xkjq013)Environment Conservation Research Centre of Xin’an River Basin (kypt202002)。
文摘Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences.
基金supported by the National Science Foundation of China(No.31770672 and 3137062)the National Basic Research Program of China(No.2010CB950602)。
文摘Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition.
基金Supported by General Project of Natural Science Research in Colleges and Universities in Anhui Province(KJHS2019B13)School-level Talents Start-up Project of Huangshan University(2019xkjq012)+1 种基金Horizontal Topic of Huangshan University(hxkt2020023)Undergraduate Innovation and Entrepreneurship Training Program of Anhui Province(S202110375082).
文摘[Objectives]This study was conducted to provide good basic research data for Cunninghamia lanceolata plantations in southern Anhui,so as to improve local ecological,economic and social benefits.[Methods]A 22-year-old near-mature C.lanceolata plantation in Lingnan Forest Farm,Xiuning County,Huangshan City,Anhui Province was investigated and analyzed by sample plot survey.[Results]The average DBH value of the C.lanceolata plantation at the lower slope was the largest,24.7%and 19.2%higher than those at the upper and middle slopes,respectively.The average single plant wood volume at the lower slope was 47.6%and 49.1%higher than those in the upper and middle slopes,respectively.However,the average tree heights at various slope positions showed little difference.Meanwhile,all the indexes showed the phenomenon of semi-shady slope>sunny slope>shady slope under different slope directions.Among them,the effect of slope position on DBH was extremely significant,but the effect of slope direction on DBH was not significant,and slope position,slope direction and the interaction of slope direction and slope position had no significant effects on the tree height of the C.lanceolata plantation.In addition,slope direction and slope position had extremely significant effects on single plant wood volume.From the overall growth situation of the C.lanceolata plantation in Lingnan Forest Farm,the slope position factor had greater effects on various indexes of forest growth than the slope direction factor,mainly manifested in that the lower slope was better than the middle slope,and the middle slope position was better than the upper slope,while although slope direction had some effect on the growth of the C.lanceolata plantation,the influence degree was not as significant as that of slope position.[Conclusions]This study provides some reference for the adjustment and optimization,development and renewal of C.lanceolata plantation structure in the later period in this area,as well as some data support for other theoretical research on economic forests.
基金Sponsored by Germplasm Collection and Conservation Project for the Forest and Grass Germplasm Resources in Anhui Province in 2024(hxkt2024111)Science and Technology Plan Project of Huangshan(2022KN-02)+1 种基金Humanities and Social Sciences Research Project of Anhui Higher Education Institutions(SKHS2019B07)Key School-level Project of Huangshan University(2022xkjzd004).
文摘The continuous progress of urbanization has driven the continuous development and innovation of landscape planning and design.Focused on the important design method of modern construction art,this study analyzed its concepts and characteristics,and made deep exploration to its application in landscape planning and design.The results indicated that modern construction art had a significant impact on landscape spatial planning and layout,spatial design forms,and spatial ornaments.The use of modern construction art concepts could make landscape design more scientific,artistic,and humane,creating higher quality leisure and entertainment venues for audiences.
基金funded by the National Natural Science Foundation of China(NSFC 31071891,31471968)Natural Science Foundation of the Education Department of Anhui Province of China(No.KJ2014A244)the Zoology and Conservation Biology Research Innovation Group of Huangshan University
文摘Many anuran species exhibit striking color and/or pattern polymorphisms. We sampled 599 adult rice frogs, Fejervarya multistriata, from a rice paddy in the periphery of the Lingnan Nature Reserve （Huangshan, Anhui）. We recognized ten morphs based on three relatively stable and distinct morphological characters： dorsal ground color （green or gray）, middorsal stripe （absence, wide, or narrow）, occipital rusty spot （absence or presence）. The grey individuals are more common and larger than the green individuals （frequency 88.1 vs. 11.9%, respectively） and （SVL 39.4-36.6 vs. 35.7-34.6 mm, respectively）. There is a higher proportion of individuals with a middorsal stripe （59.7%） while absence of the occipital rusty spot is more common in the population （82.3%）. We expect additional studies in different habitat types would help build our understanding of the relationship between color polymorphism and habitat, geography, and climate.
基金Foundation items： This research was funded by the National Natural Science Foundation of China （NSFC 30870290, 31071891 and 31471968）ACKNOWLEDGEMENTS We extend our thanks to Dr. Robert W. MURPHY for his valuable comments on this manuscript. We thank Jin-Min CHEN （Yunnan University）, Bao-Lin ZHANG （Kunming Institute of Zoology, CAS） and Li-Fang PENG （Nanjing Forestry University） for their help in data processing. We further thank Dian- Cheng YANG （Nanjing Forestry University） and Jun-Sheng CUI （Anhui Agricultural University） for sampling.
文摘Six main mitochondrial DNA （mtDNA） lineages have been described in minnow （Zacco platypus） samples obtained from northern, western and southern China Perdices et al. （2004） predicted that further sampling of other tributaries might discover more lineages of this species. In this study, we collected 26 Zacco platypus individuals in the Huangshan area of eastern China and determined the cytochrome b （cytb） sequence variations. Combined with reported data in GenBank, we identified ten matrilines （Zacco A-J） in a total of 169 samples, with relatively high molecular divergence found among them. The Huangshan population had the greatest genetic variation among all sampled regions and hosted six of the ten matrilines. Our results highlight the significance of the Huangshan area for the conservation of Zacco platypus.
基金supported by Humanities Society Scientific Research Project of Anhui Higher Education Institutions (Grant No. SK2017A0382)Anhui Province Key Innovation and Development Research Project (Grant No. 2018CX035)+5 种基金Huizhou Culture Project of Huangshan University (Grant No. 2017xhwh014)Anhui Province Project of Support Plan for Excellent Youth Talents in Colleges and Universities (Grant No. gxyqZD2018076)Huangshan University Research Platform Construction Project (Grant No. kypt201812)Provincial Undergraduate Innovation and Entrepreneurship Training Program (Grant No. AH201610375038)National Undergraduate Innovation and Entrepreneurship Training Program (Grant No. 201710375007)National Undergraduate Innovation and Entrepreneurship Training Program (Grant No. 201710375032)
文摘With the increasingly prominent problems of ecology, environment and resources in China, green economy development is becoming more and more urgent. Innovation has become the key driving force of economic development. Economic development of Huangshan City should take the road of "green development " and combine economic development with ecological protection. This paper designs the measurement index of innovation and green economic development, and makes an empirical analysis based on the data of innovation and green economic development in Huangshan City from 2005 to 2016. It is concluded that the index of innovation and green economic development in Huangshan City shows an increasing trend. Innovation has a positive role in promoting green economic development in Huangshan City. Therefore, Huangshan City should strengthen regional innovation management, create regional innovation environment, strengthen cooperation between industry, University and research, increase support for green innovation, promote technological innovation of recycling, and promote the construction of circular economy.
基金supported by the National Natural Science Foundation of China(Grant No.32171530 and 31472020)。
文摘Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests.
基金Supported by Youth Project of Natural Science Foundation of Anhui Province(2008085QC134)Natural Science Research Project in Colleges and Universities in Anhui Province(KJHS2019B09)+2 种基金School-level Talent Start-up Project(2020xkjq009)Key Project of Anhui Provincial Department of Education(2023AH051375)Key Project of Natural Science Research of Anhui Provincial Department of Education(KJ2020A0691).
文摘[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis.
基金supported by project fund support Key Project of Philosophy and Social Sciences of Anhui Province,China(2022AH051929)Analysis on the Construction of College Students’Innovation and Entrepreneurship Education System under the Digital Economy Environment(2021jyxm1404)+1 种基金Innovation and Entrepreneurship Training Program for College Students(Inspiration from the Development of Huizhou Salt Merchants in Ming and Qing Dynasties to the Production and Management of Modern Enterprises,2210375144)Exploration of Collaborative Education Path between Labor Education and Innovation and Entrepreneurship Education in Colleges and Universities in the New Era(2021jyxm1392).
文摘With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online courses,digital platforms,and value co-creation have brought new opportunities and challenges to the content,mode,and mechanism of innovation and entrepreneurship education.This paper discusses the content and new opportunities of digital entrepreneurship,analyzes the differences between traditional entrepreneurship and digital entrepreneurship,and puts forward the strategy path of entrepreneurship education under the digital economy.
基金The Institute of Soil Science ,CAS(No.035116) the Education Bureau of Zhejiang Province Program(No.20040187) andthe National Natural ScienceFoundation of China(No.40271060)
文摘Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors（BCFs） of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots （0.58-2.28）. BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L.
基金Project supported by the National Natural Science Foundation of China(Nos.40432004 and 20677015)the Postdoctoral Science Foundation of China(No.20070420094)+2 种基金the Postdoctoral Science Foundation of Shanghai Municipality,China(No.08R214116)the Science and Technology Commission of Shanghai Municipality,China(No.0752nm025)theNational High-Tech Research and Development Program(No.2007AA06Z331)
文摘Phytoremediation has been used as an emerging technology for remediation of soil contamination with polycyclic aromatic hydrocarbons(PAHs),ubiquitous persistent environmental pollutants derived from natural and anthropogenic processes,in the last decade.In this study,a pot experiment was conducted to investigate the potential of phytoremediation of pyrene from spiked soils planted with white clover(Trifolium repens)in the greenhouse with a series of pyrene concentrations ranging from 4.22 to 365.38 mg kg-1.The results showed that growth of white clover on pyrenecontaminated soils was not affected.The removal of pyrene from the spiked soils planted with white clover was obviously higher than that from the unplanted soils.At the end of the experiment(60 d),the average removal ratio of pyrene in the spiked soils with white clover was 77%,which was 31%and 57%higher than those of the controls with or without micobes, respectively.Both roots and shoots of white clover took up pyrene from the spiked soils and pyrene uptake increased with the soil pyrene concentration.However,the plant-enhanced dissipation of soil pyrene may be the result of plant-promoted microbial degradation and direct uptake and accumulation of pyrene by white clover were only a small part of the pyrene dissipation.Bioconcentration factors of pyrene(BCFs,ratio of pyrene,on a dry weight basis,in the plant to that in the soil)tended to decrease with increase in the residual soil pyrene concentration.Therefore,removal of pyrene in the contaminated soils was feasible using white clove.
基金Supported by the Fundamental Research Funds of Panjin Industrial Technology Institute(PJYJY2016A004)the National Natural Science Foundation of China(No.21776032)+2 种基金Natural Science Foundation of Anhui Province(1808085QB51)the Key Research and Development Plan of Anhui Province(1804a09020072)the Natural Science Research Project of Anhui Colleges and Universities(KJ2017A397)
文摘Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh conditions.Development of durable and high separation performance membranes with lower fabrication and operation cost are highly demanded for industrial applications. Zeolite T membrane possesses good acid-resistance with excellent hydrophilic properties as compared to NaA zeolite membrane and can be extended to industrial organic dehydrations under an acidic environment. In the present review the research advances in development of zeolite T membranes for the dehydration of organic mixtures in acidic conditions are summarized. Especially the low temperature synthesis, and epitaxial growth of the zeolite membrane with high performance are well addressed, besides emphasis is particularly placed on ensemble synthesis of hollow fiber zeolite T membrane module and its future prospects for industrial separations.
基金funded by the National Natural Science Foundation of China (31471968, 31090250, 31372152)supported by grants from the Ministry of Science and Technology of China (MOST Grant 2011FY120200)+5 种基金the Chinese Academy of Sciences (CAS KSCX2EW-Z-2 KSCX2-EW-Q-9)the Bureau of Science and Technology of Yunnan Province to ZYPthe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)the Department of education of Sichuan Province (13TD0027)
文摘The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes （2 females, 1 male） were sampled in Shangri-La, northern Yunnan, China, thus expanding their known distribution region towards the southeast. This site is the southeastern-most corner of the Tibetan Plateau and the southernmost tip of the Hengduan Mountains （Mts.）. Phylogenetic analysis of mitochondrial （mt） and nuclear （n） DNA segments suggested that the three specimens belong to the genus ofThermophis. Morphologically, the new species is more similar toT. zhaoermii. However, it is distinguished fromT.zhaoermiiin the number of maxillary teeth （15）, distance between the two eyes/head width, rostral width/height, mental width/height, in one character limited to female： head width/length, and in four characters restricted to male： occurrence of the reduction from 10 to 8 （8 to 6, 6 to 4） scales in each dorsal row on the tail. There are differences in morphology, genetics （mtDNA, nDNA）, and geography between the putative new species andT.zhaoermii,the new species meets our proposed eclectic and feasible ＂four-differences＂ rule.
文摘The hot deformation characteristics of as-forged Ti−3.5Al−5Mo−6V−3Cr−2Sn−0.5Fe−0.1B−0.1C alloy within a temperature range from 750 to 910℃and a strain rate range from 0.001 to 1 s^(-1) were investigated by hot compression tests.The stress−strain curves show that the flow stress decreases with the increase of temperature and the decrease of strain rate.The microstructure is sensitive to deformation parameters.The dynamic recrystallization(DRX)grains appear while the temperature reaches 790℃at a constant strain rate of 0.001 s^(-1) and strain rate is not higher than 0.1 s^(-1) at a constant temperature of 910℃.The work-hardening rateθis calculated and it is found that DRX prefers to happen at high temperature and low strain rate.The constitutive equation and processing map were obtained.The average activation energy of the alloy is 242.78 kJ/mol and there are few unstable regions on the processing map,which indicates excellent hot workability.At the strain rate of 0.1 s^(-1),the stress−strain curves show an abnormal shape where there are two stress peaks simultaneously.This can be attributed to the alternation of hardening effect,which results from the continuous dynamic recrystallization(CDRX)and the rotation of DRX grains,and dynamic softening mechanism.
基金supported by the National Natural Science Foundation of China(30870290)the Science Research Program of Huangshan University(2006xkjq014)
文摘The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Sichuan Province,China.Species identity was difficult to delimit morphologically because the specimens were juveniles and partially damaged.Subsequently,a molecular phylogenetic approach was used.Portions of three mitochondrial genes(cyt b,ND4 and 12S rRNA) were sequenced and analyzed.The results showed that they were sister to the genus Elaphe.Very little genetic variation was found among the three samples.The minimum genetic distances between these samples and those within Elaphe were greater than any currently recognized species within the genus.We conclude that this likely represents a new species within the genus Elaphe.Adult specimens and a morphologic description are needed for further study.
基金supported by the Natural Science Research Project of Anhui Educational Committee (No. KJ2013B273)the National Students’ Innovative Training Program (No. 201210375035)the Scientific Research Foundation for Introduced Scholars, Huangshan University (No. 2013xkjq004 ).
文摘This paper mainly covers a method for preparing a highly alkaline magnesium linoleate solution with a total base number(TBN) value of 328 mg KOH/g using linoleic acid as the biodegradable raw material, which can substitute for traditional lubricant detergents as an environmentally friendly detergent. Reaction conditions, including the molar ratio of magnesium oxide to linoleic acid, the molar ratio of methanol to magnesium oxide, the carbonation temperature, the molar ratio of water to magnesium oxide, the flow rate of CO2 gas and the duration for injection of CO2 to magnesium oxide system, were optimized.
基金funded by the National Natural Science Foundation of China（NSFC 31071891,31471968）
文摘One juvenile and one adult female wolf snake（Colubridae： Lycodon） were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon liuchengchaoi based on external morphology and molecular data. This is a new reptile record in Anhui Province. In our laboratory, four eggs were laid and three neonates were hatched successfully. This is the first record of the laying and incubation of L. liuchengchaoi eggs. The five specimens were deposited at the Museum of Huangshan University（HUM20140001） and Guangdong Entomological Institute（HB-lcfsp12613, HB-lcfsp-ch1~3）.
基金This paper was partially supported by a project of the Shanghai Science and Technology Committee(18510760300)Anhui Natural Science Foundation(1908085MF178)Anhui Excellent Young Talents Support Program Project(gxyqZD2019069).
文摘In computer vision fields,3D object recognition is one of the most important tasks for many real-world applications.Three-dimensional convolutional neural networks(CNNs)have demonstrated their advantages in 3D object recognition.In this paper,we propose to use the principal curvature directions of 3D objects(using a CAD model)to represent the geometric features as inputs for the 3D CNN.Our framework,namely CurveNet,learns perceptually relevant salient features and predicts object class labels.Curvature directions incorporate complex surface information of a 3D object,which helps our framework to produce more precise and discriminative features for object recognition.Multitask learning is inspired by sharing features between two related tasks,where we consider pose classification as an auxiliary task to enable our CurveNet to better generalize object label classification.Experimental results show that our proposed framework using curvature vectors performs better than voxels as an input for 3D object classification.We further improved the performance of CurveNet by combining two networks with both curvature direction and voxels of a 3D object as the inputs.A Cross-Stitch module was adopted to learn effective shared features across multiple representations.We evaluated our methods using three publicly available datasets and achieved competitive performance in the 3D object recognition task.
基金This work was supported by the Key Laboratory of Safety and High-Efficiency Coal Mining,Ministry of Education,Anhui University of Science and Technology(JYBSYS2020209)the Natural Science Research Project of Anhui Provincial Department of Education(KJHS2020B13)the Huangshan University School Level Talent Launch Project(No.2020XKJQ001).
文摘A mixture of fault gouge and rubble taken out from a fault zone is used to prepare a S-RM(Soil-Rock Mixture)sample with rock block proportions of 20%,30%,40%,50%,60%and 70%,respectively.A GDS triaxial test system is used accordingly to measure the seepage characteristics of such samples under different loading and unloading confining pressures in order to determine the variation law of the permeability coefficient.The test results show that:(1)The permeability coefficient of the S-RM samples decreases as the pressure increases,and the decrease rate of this coefficient in the initial stage of confining pressure loading is obviously higher than in the semi-late period;(2)The permeability coefficient at different confining pressure levels presents a common trend as the rock block proportion is increased,i.e.,it decreases first then it increases(the permeability coefficient of the sample with rock block proportion 40%being the smallest,70%the largest);(3)In the stage of confining pressure unloading,the recovery degree of the permeability coefficient grows with the increase of rock block proportion(the recovery rate of S-RM sample with rock block proportion 70%reaches 50.2%);(4)In the stage of confining pressure loading and unloading,the sensitivity of the permeability coefficient to the rock block proportion displays the inverse“Z”variation rule(when rock block proportion reaches 60%,the sensitivity is highest);(5)In the stage of confining pressure loading,the relationship between the permeability coefficient and confining pressure can be described by an exponential relationship.
