Man-made lakes are alternative and potential habitats for biodiversity conservation, fisheries and extensive aquaculture. We investigated the ecology and the fish community structure of two (2) sand-dragged man-made l...Man-made lakes are alternative and potential habitats for biodiversity conservation, fisheries and extensive aquaculture. We investigated the ecology and the fish community structure of two (2) sand-dragged man-made lakes, Lake Ahozon and Lake Bewacodji of Southern Benin, with implications for species conservation, fisheries management and aquaculture valorization. From August 2014 to July 2015, habitats conditions were evaluated and fishes were sampled monthly with seine, cast net, experimental gill net and hooks in the open water and aquatic vegetation habitats of both lakes. Overall, the water quality of Lake Ahozon was globally favorable for the growth and the survival of the fish resources whereas Lake Bewacodji exhibited a poor water quality indicated mainly by an acid pH (mean: 6.32 ± 0.58) and low dissolved oxygen concentrations (mean: 3.52 ± 1.25 mg/l) caused by dense floating plants, Nymphea sp mainly and huge daily dumping of domestic wastes. The study revealed low species richness, d = 5.89 and d = 3.87, and low species diversity, H’ = 0.76 and H’ = 0.48 for Lakes Ahozon and Bewacodji, respectively, with Lake Ahozon more diverse than Lake Bewacodji. The fish community of Lake Ahozon comprised six (6) species, 3 cichlids Sarotherodon galilaeus, Oreochromis niloticus and Tilapia guineensis, the silver catfish, Chrysichthys nigrodigitatus (Claroteidae), the African bonytongue, Heterotis niloticus (Osteoglossidae), and the African catfish, Clarias gariepinus (Clariidae). Numerically, S. galilaeus dominated Lake Ahozon and made 85.21% of the sample. In Lake Bewacodji, the fish composition comprised four (4) species, Sarotherodon galilaeus multifasciatus, the dominant species making numerically 91.58% of the total sample, T. guineensis, C. gariepinus and C. nigrodigitatus. With regard to trophic structure, the fish assemblages of both lakes were numerically dominated by planktinovores/ detritivores, mainly S. galilaeus, O. niloticus, T. guineensis and C. nigrodigitatus making together 99.46% of Lake Ahozon fish community, and S. galilaeus multifasciatus, T. guineensis and C. nigrodigitatus accounting together for about 98.59% of Lake Bewacodji. In Lake Ahozon, standard length (SL) frequencies histograms showed an unimodal size distribution for H. niloticus, the nile tilapia O. niloticus and C. gariepinus whereas the two cichlids, S. galilaeus and T. guineensis exhibited a bimodal size distribution. In Lake Bewacodji, S. galilaeus multifasciatus, C. nigrodigitatus and C. gariepinus exhibited an unimodal size distribution. A sustainable exploitation of both man-made lakes requires the implementation of an integrated management scheme which should include habitat restoration and protection plan, fisheries/aquacultural valorization, ecological sound agriculture/ecotourism and environmental monitoring. 展开更多
The freshwater cichlid, Sarotherodon galilaeus (Linné, 1758) is an economically and commercially important fisheries species that has naturally colonized and dominated a sand-dragged man-made freshwater lake of A...The freshwater cichlid, Sarotherodon galilaeus (Linné, 1758) is an economically and commercially important fisheries species that has naturally colonized and dominated a sand-dragged man-made freshwater lake of Ahozon (South-Benin) where the species made about 85.21% of the fish community. We investigated the feeding ecology of S. galilaeus in order to evaluate resource exploitation and the establishment of this species in Lake Ahozon. During wet, flood and dry seasons, 1189 individuals of S. galilaeus have been monthly sampled in the open water and in the aquatic vegetation habitats. The study showed that S. galilaeus consumed about seventy (70) food items dominated by algae (52.88%) composed of 28 families and 52 genera from blue-green algae, green algae, desmids, and diatoms, sand particles (23.95%), detritus (12.27%) and protozoans (7.68%). Minor preys were rotifers, copepods, cladodera, crustacea and insect parts. Foods items with higher diet occurrence were sand particles with a percentage occurrence of 72.33%, detritus (69.47%), and some algae such as Scenedesmus (58.96%), Closterium (55.68%), and Microcystis (51.30%). Significant (P ≤ 0.05) ontogenetic variations of empty stomachs were recorded. S. galilaeus exhibited a wide diet breadth (DB) ranging between 5.55 and 7.29 that tended to increase with fish sizes. Diet overlaps (Øjk) varied from 0.77 to 0.97, indicating high diet similarities between different life stage categories. The slope b = 0.560 obtained from Log (body weight)-Log (gut length) linear regression, and the mean ratio of GL/SL = 6.72 ± 2.23 support our findings that S. galilaeus exhibited detritivorous, herbivorous and omnivorous food habits. The broad spectrum of food resources consumed/utilized and the high diet breadth recorded leading to allometric growth, the active breeding and the high propagation of the species, were some indicators of the successful establishment of S. galilaeus in the man-made lake of Ahozon. Sustainable fisheries/ aquaculture exploitation of S. galilaeus and successful valorization of the man-made lake of Ahozon require an integrated management of the lake including the prevention of domestic waste dumpings, the protection of the foraging and spawning grounds, the fertilization of the lake, the introduction of predators to control the population of S. galilaeus , the protection of lake margin to avoid erosion, a planned harvest of the fish stock and a periodic ecological monitoring of Lake Ahozon.展开更多
Investigations of ^(239+240)Pu and ^(238)Pu in the surface layer(0–5 cm) of bottom sediment in the Crimean 10 salt lakes from 4 geographical groups were carried out for the first time. The ^(239+240)Pu varied widely ...Investigations of ^(239+240)Pu and ^(238)Pu in the surface layer(0–5 cm) of bottom sediment in the Crimean 10 salt lakes from 4 geographical groups were carried out for the first time. The ^(239+240)Pu varied widely between regional geographical groups of lakes as well as within groups too and ranged from 11±4 to 451±43 mBq^(239+240)Pu/kg. The highest levels of ^(239+240)Pu—419±27, 443±24 and 451±43 mBq/kg were observed in the Yevpatoriya(Lake Kyzyl-Yar), the Tarkhankut(Dzharylhach) and the Kerch group(Tobechik), respectively. The lowest values of ^(239+240)Pu were identified in three lakes of the Perekop group and were 20±12, 24±6 and 48±6 mBq/kg. In all lakes ^(238)Pu was an order of magnitude lower than 239+240 Pu and varied from 4.8±2.6 to 30.7±5.5 mBq/kg. The ^(238)Pu activity was decay-corrected to 1986. The characteristic ratio of the ^(238)Pu/239+240 Pu activities in the sediment and percentage of the Chernobyl-derived Pu was calculated. The largest percentages of the Chernobyl-derived Pu were observed in the Evpatoriya group(Lake SasykSivash)—16.2%±8.26%, the Tarkhankut group(Dzharylhach)—8.4%±2.10% and the Kerch group(Aktash)—10.5%±5.56%. The study of the depth distribution of plutonium in the Lake Kyzyl-Yar bottom sediment core(0–25 cm) was fulfilled. It was shown that 239+240 Pu was high enough in all studied layers of bottom sediment, but the highest activity ratio ^(238)Pu/239+240 Pu(0.062±0.020) was found in the deepest layer of 15–20.5 cm and the percentage of Chernobyl-derived Pu was estimated at 6.8%±2.85% in this layer.展开更多
Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within...Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within shallow wetland lakes remains limited.This study investigated the occurrence and bioaccumulation of ten commonly used antibiotics in the Baiyang Lake,northern China’s largest shallow wetland lake.The results indicated that sulfonamides and fluoroquinolones were the predominant antibiotics in surface water,whereas fluoroquinolones and macrolides were more prevalent in sediment.Fluoroquinolones demonstrated significant potential for bioaccumulation in targeted aquatic organisms,including both animals and plants(Carassius au-ratus and Phragmites australis).The bioaccumulation of antibiotics in Carassius auratus was correlated with their solubility,whereas in Phragmites australis,this was associated with their octanol-water partition coefficients and molecular weights.Ecological risk assessment indicated that most antibiotics posed minimal to low risk levels.However,four antibiotics were exceptions:clarithromycin(12.5%)and sulfamethoxazole(6.25%)presented a high risk in surface water samples,while norfloxacin(25.0%)and ciprofloxacin(25.0%)posed a high risk in sediment samples.Norfloxacin,ciprofloxacin,and roxithromycin were identified as key indicator antibiotics for enhancing the local monitoring and control of antibiotic contamination based on four criteria:(1)high con-centrations,(2)frequent detection,(3)capacity for bioaccumulation,and(4)ecological risk levels.This study contributes to a deeper understanding of the status of antibiotic contamination,bioaccumulation characteristics,and ecological risk in Baiyang Lake,thereby supporting efforts to monitor and regulate antibiotic pollution.展开更多
Lakes are carbon dioxide(CO_(2))and methane(CH_(4))emission hotspots,whose associated flux is spatially vari-able.Many studies have investigated the impact of microorganisms and environmental factors on CO_(2) and CH_...Lakes are carbon dioxide(CO_(2))and methane(CH_(4))emission hotspots,whose associated flux is spatially vari-able.Many studies have investigated the impact of microorganisms and environmental factors on CO_(2) and CH_(4) emissions between different lakes.However,the carbon emissions and their influencing factors of different areas within a single lake remain poorly understood.Accordingly,this study investigates CO_(2) and CH_(4) emission hetero-geneity in a large floodplain lake system and distribution characteristics of associated functional microorganisms.Findings show that mean CO_(2) and CH_(4) flux values in the sub lake area were 62.03±24.21 mg/(m2·day)and 5.97±3.2μg/(m2·day),which were greater by factors of 1.78 and 2.96 compared to the water channel and the main lake area,respectively.The alpha diversity of methanogens in the sub lake area was lower than that in the main lake and water channel areas.The abundance of methanogens in bottom water layer was higher compared with the middle and surface layers.Conversely,the abundance of methane(CH_(4))-oxidizing bacteria in the surface layer was higher than that in the bottom layer.Additionally,the composition of methanogen and CH_(4)-oxidizing bacterial community,chlorophyll a(Chl-a),pH,total phosphorus(TP)and dissolved organic carbon(DOC)con-tent constituted the dominate driving factors affecting lake C emissions.Results from this study can be used to improve our understanding of lake spatial heterogeneous of CO_(2) and CH_(4) emission and the driving mechanisms within floodplain lakes under the coupling effects of functional C microorganisms and environmental factors.展开更多
While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest fre...While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest freshwater system,and in many ways resemble marine ecosystems.However,unlike the open ocean and coastal waters where pH has declined due to rising atmospheric CO_(2),no significant pH trends have been observed in the Laurentian Great Lakes,despite significant ecosystem changes driven partly by the invasion of dreissenid mussels.This study examined 41 years of field observations from Lake Michigan to investigate the long-term carbonate chemistry dynamics.Observational results revealed substantial declines in both total alkalinity(TA)and dissolved inorganic carbon(DIC)over the four decades.Mussel shell calcification emerged as the primary mechanism behind these declines,accounting for 97%and 47%of the observed changes in TA and DIC,respectively,lowering water column pH by 0.24 units.Elevated carbon accumulation in soft mussel tissues,coupled with long-term changes in the air-water pCO_(2)gradient during summer,significantly contributed to long-term DIC variations,explaining 18%and 28%of the lake-wide DIC loss.These two mechanisms also resulted in an overall pH increase of 0.09 and 0.12 units,largely offsetting the calcification-driven pH decrease.These findings bridge a gap in acidification research for large freshwater systems and provide valuable insights for comprehensive lake-wide management strategies.展开更多
Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbani...Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbanization remain unclear.This study explored the spatiotemporal evolution of ER and urbanization in five GLRs in China to analyze the ER dynamic patterns along center−lakeside−periphery gradient.The Spatial Durbin Model(SDM)and Panel Threshold Model(PTM)were combined to reveal the spillover and threshold effects of urbanization in five GLRs.The results indicate that the ER in five GLRs declined with a rate of 21%from 2000 to 2020.There was a clear“center-periphery”contraction trend with low ER areas primarily spreading to human activity-concentrated regions such as lakesides,riversides,and road networks.Driven by economic and land urbanization,the average urbanization level increased from 0.06 to 0.13,where lakesides,riversides,and road networks were key areas undergoing expansion.The urbanization showed a noticeable negative spatial spillover effect on ER.Away from central lakes,the negative impacts on ER exhibited a two-phase decrease with the threshold of 81 km.This study contributes to the understanding of human-environment interactions by examining the ecological resilience response process of GLRs under the impact of urbanization.Based on a multidimensional“center−lakeside−periphery”analytical model,this study provides a strategic framework for ecological construction in GLRs in China,promoting sustainable development and adaptive capacity in vulnerable areas.展开更多
Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have n...Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have not been thoroughly investigated.In this study,multiple tracers(hydrochemistry,𝛿D,𝛿18O and 222Rn)were used to compare mechanisms of LGD in Daihai and Ulansuhai Lake in Inner Mongoli1,Northwest China.The hydrochemical types showed a trend from groundwater to lake water,indicating a hydraulic connection between them.In addition,the𝛿D and𝛿18O values of sediment pore water were between the groundwater and lake water,indicating the LGD processes.The radon mass balance model was used to estimate the average groundwater discharge rates of Daihai and Ulansuhai Lake,which were 2.79 mm/day and 3.02 mm/day,respectively.The total nitrogen(TN),total phosphorus(TP),and fluoride inputs associated with LGD in Daihai Lake accounted for 97.52%,96.59%,and 95.84%of the total inputs,respectively.In contrast,TN,TP and fluoride inputs in Ulansuhai Lake were 53.56%,40.98%,and 36.25%,respectively.This indicates that the pollutant inputs associated with LGD posed a potential threat to the ecological stability of Daihai and Ulansuhai Lake.By comparison,the differences of LGD process and associated pollutant flux were controlled by hydrogeological conditions,lakebed permeability and human activities.This study provides a reference for water resources management in Daihai and Ulansuhai Lake basins while improving the understanding of LGD in the Yellow River basin.展开更多
Objective Category-specific recognition and naming deficits have been observed in a variety of patient populations. However, the category-specific cortices for naming famous faces, animals and man-made objects remain ...Objective Category-specific recognition and naming deficits have been observed in a variety of patient populations. However, the category-specific cortices for naming famous faces, animals and man-made objects remain controversial. The present study aimed to study the specific areas involved in naming pictures of these 3 categories using functional magnetic resonance imaging. Methods Functional images were analyzed using statistical parametric mapping and the 3 different contrasts were evaluated using t statistics by comparing the naming tasks to their baselines.The contrast images were entered into a random-effects group level analysis.The results were reported in Montreal Neurological Institute co-ordinates,and anatomical regions were identified using an automated anatomical labeling method with XJview 8.Results Naming famous faces caused more activation in the bilateral head of the hippocampus and amygdala with significant left dominance. Bilateral activation of pars triangularis and pars opercularis in the naming of famous faces was also revealed. Naming animals evoked greater responses in the left supplementary motor area, while naming man-made objects evoked more in the left premotor area,left pars orbitalis and right supplementary motor area. The extent of bilateral fusiform gyri activation by naming man-made objects was much larger than that by naming of famous faces or animals.Even in the overlapping sites of activation,some differences among the categories were found for activation in the fusiform gyri.Conclusion The cortices involved in the naming process vary with the naming of famous faces,animals and man-made objects.This finding suggests that different categories of pictures should be used during intra-operative language mapping to generate a broader map of language function, in order to minimize the incidence of false-negative stimulation and permanent post-operative deficits.展开更多
This paper describes the interaction between deep-seated landslides and man-made structures such as dams, penstocks, viaducts, and tunnels. Selected case studies are reported first with the intent to gain insights int...This paper describes the interaction between deep-seated landslides and man-made structures such as dams, penstocks, viaducts, and tunnels. Selected case studies are reported first with the intent to gain insights into the complexities associated with the interaction of these structures with deep-seated landslides(generally referred to as deep-seated gravity slope deformations, DSGSDs). The main features, which characterize these landslides, are mentioned together with the interaction problems encountered in each case. Given the main objective of this paper, the numerical modeling methods adopted are outlined as means for increase in the understanding of the interaction problems being investigated. With the above in mind, the attention moves to an important and unique case history dealing with the interaction of a large-size twin-tunnel excavated with an earth pressure balance(EPB)tunnel boring machine(TBM) and a deep-seated landslide, which was reactivated due to the stress changes induced by tunnel excavation in landslide shear zone. The geological and geotechnical conditions are described together with the available monitoring data on the landslide movements, based on the advanced and conventional monitoring tools used. Numerical modeling is illustrated as an aid to back-analyze the monitored surface and subsurface deformations and to assist in finding the appropriate engineering solution for putting the tunnel into service and as a follow-up means for future understanding and control of the interaction problems. The simulation is based on a novel time-dependent model representing the landslide behavior.展开更多
Man-made object detection is of great significance in both military and civil areas, such as search-and-rescue missions at sea, traffic signs recognition during visual navigation, and targets location in a military st...Man-made object detection is of great significance in both military and civil areas, such as search-and-rescue missions at sea, traffic signs recognition during visual navigation, and targets location in a military strike. Contours of man-made objects usually consist of straight lines, corner points, and simple curves. Motivated by this observation, a man-made object detection method is proposed based on complexity evaluation of object contours. After salient contours which keep the crucial information of objects are accurately extracted using an improved mean-shift clustering algorithm, a novel approach is presented to evaluate the complexity of contours. By comparing the entropy values of contours before/after sampling and linear interpolation, it is easy to distinguish between man-made objects and natural ones according to the complexity of their contours.Experimental results show that the presented method can effectively detect man-made objects when compared to the existing ones.展开更多
In this study the regeneration diversity of Syahkal forests afforestated and natural stands in north of Iran was studied and compared from the point of view of evenness and diversity index. In order to accomplish this...In this study the regeneration diversity of Syahkal forests afforestated and natural stands in north of Iran was studied and compared from the point of view of evenness and diversity index. In order to accomplish this study two natural and man-made stands that almost are located in the same height above the sea level were chosen. The area of each stand was 30 ha and the inventory was done by the random-systematic method with a 5R land measurement (500 m2) selected. Also, in order to study the regeneration in the center of each sample piece 125 square meters micro plots were formed. The results show that regeneration diversity index in natural stands is more than that in man-made stands which in this case Mc-Arthur index with 2.41 has the most amount while Simpson index with 0.543 has the least amount. But the evenness indexes in man-made stands are more than that in natural stand which the main reason is the purity of the man-made stand.展开更多
This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducte...This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducted experiments to investigate the influence of four factors related to solar pond structure on the crystallization of Li_(2)CO_(3) and their pairwise interactions.Computational Fluid Dynamics(CFD)simulations of the flow field within the solar pond were performed using COMSOL Multiphysics software to compare temperature distributions before and after optimization.The results indicate that the optimal structure for lithium extraction from the Zabuye Salt Lake solar ponds includes UCZ(Upper Convective Zone)thickness of 53.63 cm,an LCZ(Lower Convective Zone)direct heating temperature of 57.39℃,a CO32−concentration of 32.21 g/L,and an added soda ash concentration of 6.52 g/L.Following this optimized pathway,the Li_(2)CO_(3) precipitation increased by 7.34% compared to the initial solar pond process,with a 33.33% improvement in lithium carbonate crystallization rate.This study demonstrates the feasibility of optimizing lithium extraction solar pond structures,offering a new approach for constructing such ponds in salt lakes.It provides valuable guidance for the efficient extraction of lithium resources from carbonate-type salt lake brines.展开更多
To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend tes...To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test,box plots,and violin plots.The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes,with an average water level of 12.82 m and a monthly range of 11.21–17.24m.Since 2017,the water level of Huayang Rivers has shown a decreasing trend of–0.02 m/a.Total phosphorus(TP)has become the primary pollutant.The TP concentrations in Longgan Lake(the largest lake)during the dry,rising,flood,and retreating seasons from 2015 to 2023were 0.083,0.061,0.050,and 0.059 mg/L,respectively.The effect of water level on TP was mainly observed during the low-water period.When the water level in the dry season rose to 12.25 and 13.00 m,the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8%and 33.3%,respectively.During the dry season,wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes.This led to drastic fluctuations in TP concentration,reducing the correlation between water level and TP.When external control is limited,the water level during the dry season should be maintained between 12.25 and 13.0 m.Additionally,it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans)in the Huayang Rivers.展开更多
The 25th China International Man-made Fiber Conference (Bengbu 2019)(hereinafter referred to as CIMFC 2019), themed on “Opening and Integaration for Interactive Development — Coordinated Progress of Global Man-Made ...The 25th China International Man-made Fiber Conference (Bengbu 2019)(hereinafter referred to as CIMFC 2019), themed on “Opening and Integaration for Interactive Development — Coordinated Progress of Global Man-Made Fiber Industry”, was convened in Bengbu City, Anhui Province. CIMFC 2019 was sponcored by China National Textile and Apparel Council (CNTAC), organized by China Chemical Fibers Association, Chi-na Textile International Exchange Center, and China BBCA Group Corp., supported by Bengbu Municipal People’s Goverment, and co-organized by Bengbu Investment Promotion and Foreign cooperation Center, Bengbu Municipal Bureau of Commerce and Foreign Affairs, and Oerlikon Man-made Fiber.展开更多
The behavioral responses of birds to urban environments are crucial for their ability to thrive within city landscapes.Various urban birds have demonstrated the capacity to exploit artificial structures as nesting sit...The behavioral responses of birds to urban environments are crucial for their ability to thrive within city landscapes.Various urban birds have demonstrated the capacity to exploit artificial structures as nesting sites due to the limited availability of natural options.This review examines the current state of urban bird nesting behaviors on manmade structures and highlights directions for future research.Nest types frequently observed on these structures include woven,cavity,ground,and mud nests.These adaptive behaviors increase nesting opportunities and improve reproductive success,although they may heighten vulnerability to ecological traps.Proximity to human habitats can promote conservation awareness but also presents potential economic and health-related challenges.Therefore,applying diverse strategies is essential for effectively managing and protecting nests on man-made structures across various circumstances.There is also a need for thorough,long-term studies on the ecological and evolutionary impacts of nest building on artificial structures and the mechanisms influencing nestsite selection.Furthermore,exploring innovative approaches that combine policy implementation and citizen science will be vital for advancing human-bird coexistence.展开更多
Decades of species composition changes can lead to the eutrophication-driven loss of submerged macrophytes in shallow lakes.Investigating the mechanisms of these nature-and human driven changes is crucial for the rest...Decades of species composition changes can lead to the eutrophication-driven loss of submerged macrophytes in shallow lakes.Investigating the mechanisms of these nature-and human driven changes is crucial for the restoration and management of such lakes.To investigate the changes in aquatic macrophyte communities over the past two centuries,we analyzed macrofossils in sediments from a^(210)Pb-dated core obtained in Dongping Lake in the lower Huanghe(Yellow)River Basin,eastern China.Multiple factor analysis(MFA)revealed an association between macrophyte shifts and changes in various environmental stressors(invertebrates,grain size,geochemistry,and documented records),indicating that macrophyte community changes before 1960 were predominately driven by flood disturbances.Ever since,anthropogenic pollution and the construction of water conservancy projects have caused variations in hydrology and nutrients,leading to significant changes in the composition of macrophyte communities.Macrofossil data reveal a decline in diversity and pollution-intolerant species during the late 1980 s and the early 2000 s,which is indicative of eutrophication.We also found that the current environment of Dongping Lake exhibits a clear degeneration in emergent plants and a proliferation of macrophyte species associated with eutrophic conditions,which could be attributed to water level fluctuation and nutrient input due to the water supply from the eastern route of the South-to-North Water Diversion Project as well as climate warming.Our results provide valuable insights for assessing ecosystem health and the restoration and management of Dongping Lake and similar lakes in the Huanghe River region and elsewhere.展开更多
As an important fundamental industry of the national economy,the man-made fiber industrial chain is integrated into the era development and it assumes the responsibility of advancing.Each link of the industrial chain ...As an important fundamental industry of the national economy,the man-made fiber industrial chain is integrated into the era development and it assumes the responsibility of advancing.Each link of the industrial chain is connected with each other.After the development and accumulation of several decades,the new produced polyester,PTA and other plants keep展开更多
文摘Man-made lakes are alternative and potential habitats for biodiversity conservation, fisheries and extensive aquaculture. We investigated the ecology and the fish community structure of two (2) sand-dragged man-made lakes, Lake Ahozon and Lake Bewacodji of Southern Benin, with implications for species conservation, fisheries management and aquaculture valorization. From August 2014 to July 2015, habitats conditions were evaluated and fishes were sampled monthly with seine, cast net, experimental gill net and hooks in the open water and aquatic vegetation habitats of both lakes. Overall, the water quality of Lake Ahozon was globally favorable for the growth and the survival of the fish resources whereas Lake Bewacodji exhibited a poor water quality indicated mainly by an acid pH (mean: 6.32 ± 0.58) and low dissolved oxygen concentrations (mean: 3.52 ± 1.25 mg/l) caused by dense floating plants, Nymphea sp mainly and huge daily dumping of domestic wastes. The study revealed low species richness, d = 5.89 and d = 3.87, and low species diversity, H’ = 0.76 and H’ = 0.48 for Lakes Ahozon and Bewacodji, respectively, with Lake Ahozon more diverse than Lake Bewacodji. The fish community of Lake Ahozon comprised six (6) species, 3 cichlids Sarotherodon galilaeus, Oreochromis niloticus and Tilapia guineensis, the silver catfish, Chrysichthys nigrodigitatus (Claroteidae), the African bonytongue, Heterotis niloticus (Osteoglossidae), and the African catfish, Clarias gariepinus (Clariidae). Numerically, S. galilaeus dominated Lake Ahozon and made 85.21% of the sample. In Lake Bewacodji, the fish composition comprised four (4) species, Sarotherodon galilaeus multifasciatus, the dominant species making numerically 91.58% of the total sample, T. guineensis, C. gariepinus and C. nigrodigitatus. With regard to trophic structure, the fish assemblages of both lakes were numerically dominated by planktinovores/ detritivores, mainly S. galilaeus, O. niloticus, T. guineensis and C. nigrodigitatus making together 99.46% of Lake Ahozon fish community, and S. galilaeus multifasciatus, T. guineensis and C. nigrodigitatus accounting together for about 98.59% of Lake Bewacodji. In Lake Ahozon, standard length (SL) frequencies histograms showed an unimodal size distribution for H. niloticus, the nile tilapia O. niloticus and C. gariepinus whereas the two cichlids, S. galilaeus and T. guineensis exhibited a bimodal size distribution. In Lake Bewacodji, S. galilaeus multifasciatus, C. nigrodigitatus and C. gariepinus exhibited an unimodal size distribution. A sustainable exploitation of both man-made lakes requires the implementation of an integrated management scheme which should include habitat restoration and protection plan, fisheries/aquacultural valorization, ecological sound agriculture/ecotourism and environmental monitoring.
文摘The freshwater cichlid, Sarotherodon galilaeus (Linné, 1758) is an economically and commercially important fisheries species that has naturally colonized and dominated a sand-dragged man-made freshwater lake of Ahozon (South-Benin) where the species made about 85.21% of the fish community. We investigated the feeding ecology of S. galilaeus in order to evaluate resource exploitation and the establishment of this species in Lake Ahozon. During wet, flood and dry seasons, 1189 individuals of S. galilaeus have been monthly sampled in the open water and in the aquatic vegetation habitats. The study showed that S. galilaeus consumed about seventy (70) food items dominated by algae (52.88%) composed of 28 families and 52 genera from blue-green algae, green algae, desmids, and diatoms, sand particles (23.95%), detritus (12.27%) and protozoans (7.68%). Minor preys were rotifers, copepods, cladodera, crustacea and insect parts. Foods items with higher diet occurrence were sand particles with a percentage occurrence of 72.33%, detritus (69.47%), and some algae such as Scenedesmus (58.96%), Closterium (55.68%), and Microcystis (51.30%). Significant (P ≤ 0.05) ontogenetic variations of empty stomachs were recorded. S. galilaeus exhibited a wide diet breadth (DB) ranging between 5.55 and 7.29 that tended to increase with fish sizes. Diet overlaps (Øjk) varied from 0.77 to 0.97, indicating high diet similarities between different life stage categories. The slope b = 0.560 obtained from Log (body weight)-Log (gut length) linear regression, and the mean ratio of GL/SL = 6.72 ± 2.23 support our findings that S. galilaeus exhibited detritivorous, herbivorous and omnivorous food habits. The broad spectrum of food resources consumed/utilized and the high diet breadth recorded leading to allometric growth, the active breeding and the high propagation of the species, were some indicators of the successful establishment of S. galilaeus in the man-made lake of Ahozon. Sustainable fisheries/ aquaculture exploitation of S. galilaeus and successful valorization of the man-made lake of Ahozon require an integrated management of the lake including the prevention of domestic waste dumpings, the protection of the foraging and spawning grounds, the fertilization of the lake, the introduction of predators to control the population of S. galilaeus , the protection of lake margin to avoid erosion, a planned harvest of the fish stock and a periodic ecological monitoring of Lake Ahozon.
基金supported by the Russian Foundation for Basic Research Grant No.16-05-00134
文摘Investigations of ^(239+240)Pu and ^(238)Pu in the surface layer(0–5 cm) of bottom sediment in the Crimean 10 salt lakes from 4 geographical groups were carried out for the first time. The ^(239+240)Pu varied widely between regional geographical groups of lakes as well as within groups too and ranged from 11±4 to 451±43 mBq^(239+240)Pu/kg. The highest levels of ^(239+240)Pu—419±27, 443±24 and 451±43 mBq/kg were observed in the Yevpatoriya(Lake Kyzyl-Yar), the Tarkhankut(Dzharylhach) and the Kerch group(Tobechik), respectively. The lowest values of ^(239+240)Pu were identified in three lakes of the Perekop group and were 20±12, 24±6 and 48±6 mBq/kg. In all lakes ^(238)Pu was an order of magnitude lower than 239+240 Pu and varied from 4.8±2.6 to 30.7±5.5 mBq/kg. The ^(238)Pu activity was decay-corrected to 1986. The characteristic ratio of the ^(238)Pu/239+240 Pu activities in the sediment and percentage of the Chernobyl-derived Pu was calculated. The largest percentages of the Chernobyl-derived Pu were observed in the Evpatoriya group(Lake SasykSivash)—16.2%±8.26%, the Tarkhankut group(Dzharylhach)—8.4%±2.10% and the Kerch group(Aktash)—10.5%±5.56%. The study of the depth distribution of plutonium in the Lake Kyzyl-Yar bottom sediment core(0–25 cm) was fulfilled. It was shown that 239+240 Pu was high enough in all studied layers of bottom sediment, but the highest activity ratio ^(238)Pu/239+240 Pu(0.062±0.020) was found in the deepest layer of 15–20.5 cm and the percentage of Chernobyl-derived Pu was estimated at 6.8%±2.85% in this layer.
基金supported by Hebei Natural Science Foundation(No.JZX2023018)Hebei Natural Science Foundation(No.C2022201042)the 100 Foreign Experts Plans of Hebei Province(No.606080123001).
文摘Antibiotics are widespread in aquatic environments due to their extensive use in human healthcare and ani-mal husbandry.However,research on the occurrence and bioaccumulation of antibiotics in aquatic organisms within shallow wetland lakes remains limited.This study investigated the occurrence and bioaccumulation of ten commonly used antibiotics in the Baiyang Lake,northern China’s largest shallow wetland lake.The results indicated that sulfonamides and fluoroquinolones were the predominant antibiotics in surface water,whereas fluoroquinolones and macrolides were more prevalent in sediment.Fluoroquinolones demonstrated significant potential for bioaccumulation in targeted aquatic organisms,including both animals and plants(Carassius au-ratus and Phragmites australis).The bioaccumulation of antibiotics in Carassius auratus was correlated with their solubility,whereas in Phragmites australis,this was associated with their octanol-water partition coefficients and molecular weights.Ecological risk assessment indicated that most antibiotics posed minimal to low risk levels.However,four antibiotics were exceptions:clarithromycin(12.5%)and sulfamethoxazole(6.25%)presented a high risk in surface water samples,while norfloxacin(25.0%)and ciprofloxacin(25.0%)posed a high risk in sediment samples.Norfloxacin,ciprofloxacin,and roxithromycin were identified as key indicator antibiotics for enhancing the local monitoring and control of antibiotic contamination based on four criteria:(1)high con-centrations,(2)frequent detection,(3)capacity for bioaccumulation,and(4)ecological risk levels.This study contributes to a deeper understanding of the status of antibiotic contamination,bioaccumulation characteristics,and ecological risk in Baiyang Lake,thereby supporting efforts to monitor and regulate antibiotic pollution.
基金supported by the National Natural Science Foundation of China(No.42225103).
文摘Lakes are carbon dioxide(CO_(2))and methane(CH_(4))emission hotspots,whose associated flux is spatially vari-able.Many studies have investigated the impact of microorganisms and environmental factors on CO_(2) and CH_(4) emissions between different lakes.However,the carbon emissions and their influencing factors of different areas within a single lake remain poorly understood.Accordingly,this study investigates CO_(2) and CH_(4) emission hetero-geneity in a large floodplain lake system and distribution characteristics of associated functional microorganisms.Findings show that mean CO_(2) and CH_(4) flux values in the sub lake area were 62.03±24.21 mg/(m2·day)and 5.97±3.2μg/(m2·day),which were greater by factors of 1.78 and 2.96 compared to the water channel and the main lake area,respectively.The alpha diversity of methanogens in the sub lake area was lower than that in the main lake and water channel areas.The abundance of methanogens in bottom water layer was higher compared with the middle and surface layers.Conversely,the abundance of methane(CH_(4))-oxidizing bacteria in the surface layer was higher than that in the bottom layer.Additionally,the composition of methanogen and CH_(4)-oxidizing bacterial community,chlorophyll a(Chl-a),pH,total phosphorus(TP)and dissolved organic carbon(DOC)con-tent constituted the dominate driving factors affecting lake C emissions.Results from this study can be used to improve our understanding of lake spatial heterogeneous of CO_(2) and CH_(4) emission and the driving mechanisms within floodplain lakes under the coupling effects of functional C microorganisms and environmental factors.
基金Supported by the National Natural Science Foundation of China(No.43277051)the Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes of Ministry of Education(No.B230203006).
文摘While oceanic and coastal acidification has gained increased attention,long-term pH trends and their drivers in large freshwater systems remain poorly understood.The Laurentian Great Lakes are the world’s largest freshwater system,and in many ways resemble marine ecosystems.However,unlike the open ocean and coastal waters where pH has declined due to rising atmospheric CO_(2),no significant pH trends have been observed in the Laurentian Great Lakes,despite significant ecosystem changes driven partly by the invasion of dreissenid mussels.This study examined 41 years of field observations from Lake Michigan to investigate the long-term carbonate chemistry dynamics.Observational results revealed substantial declines in both total alkalinity(TA)and dissolved inorganic carbon(DIC)over the four decades.Mussel shell calcification emerged as the primary mechanism behind these declines,accounting for 97%and 47%of the observed changes in TA and DIC,respectively,lowering water column pH by 0.24 units.Elevated carbon accumulation in soft mussel tissues,coupled with long-term changes in the air-water pCO_(2)gradient during summer,significantly contributed to long-term DIC variations,explaining 18%and 28%of the lake-wide DIC loss.These two mechanisms also resulted in an overall pH increase of 0.09 and 0.12 units,largely offsetting the calcification-driven pH decrease.These findings bridge a gap in acidification research for large freshwater systems and provide valuable insights for comprehensive lake-wide management strategies.
基金supported by the National Natural Science Foundation of China(Grants No.42301226,42271209 and 42471199)the Fundamental Research Funds for the Central Universities(Grant No.2024CDJXY014)+2 种基金the Natural Science Foundation of Jiangxi Province(Grant No.20242BAB25170)Special Funds for Water Resources in Jiangxi Province(Science and Technology Projects)(Grant No.202425YBKT16)the Young Talent Cultivation and Innovation Fund Project of Nanchang University(Grant No.XX202506030028).
文摘Great Lakes Regions(GLRs)in China often confront landscape fragmentation,wetland degradation,and ecological resilience(ER)losses owing to extensive and intensive urbanization.In GLRs,however,the ER responses to urbanization remain unclear.This study explored the spatiotemporal evolution of ER and urbanization in five GLRs in China to analyze the ER dynamic patterns along center−lakeside−periphery gradient.The Spatial Durbin Model(SDM)and Panel Threshold Model(PTM)were combined to reveal the spillover and threshold effects of urbanization in five GLRs.The results indicate that the ER in five GLRs declined with a rate of 21%from 2000 to 2020.There was a clear“center-periphery”contraction trend with low ER areas primarily spreading to human activity-concentrated regions such as lakesides,riversides,and road networks.Driven by economic and land urbanization,the average urbanization level increased from 0.06 to 0.13,where lakesides,riversides,and road networks were key areas undergoing expansion.The urbanization showed a noticeable negative spatial spillover effect on ER.Away from central lakes,the negative impacts on ER exhibited a two-phase decrease with the threshold of 81 km.This study contributes to the understanding of human-environment interactions by examining the ecological resilience response process of GLRs under the impact of urbanization.Based on a multidimensional“center−lakeside−periphery”analytical model,this study provides a strategic framework for ecological construction in GLRs in China,promoting sustainable development and adaptive capacity in vulnerable areas.
基金supported by the Natural Science Foundation of Inner Mongolia Autonomous Region of China(No.2023QN04011)the National Natural Science Foundation of China(Nos.42307092 and 52279067)+1 种基金Ordos Science and Technology Major Project(No.ZD20232303)Project of Key Laboratory of River and Lake in Inner Mongolia Autonomous Region(No.2022QZBZ0003).
文摘Lacustrine groundwater discharge(LGD)plays an important role in water resources management.Previous studies have focused on LGD process in a single lake,but the differences in LGD process within the same region have not been thoroughly investigated.In this study,multiple tracers(hydrochemistry,𝛿D,𝛿18O and 222Rn)were used to compare mechanisms of LGD in Daihai and Ulansuhai Lake in Inner Mongoli1,Northwest China.The hydrochemical types showed a trend from groundwater to lake water,indicating a hydraulic connection between them.In addition,the𝛿D and𝛿18O values of sediment pore water were between the groundwater and lake water,indicating the LGD processes.The radon mass balance model was used to estimate the average groundwater discharge rates of Daihai and Ulansuhai Lake,which were 2.79 mm/day and 3.02 mm/day,respectively.The total nitrogen(TN),total phosphorus(TP),and fluoride inputs associated with LGD in Daihai Lake accounted for 97.52%,96.59%,and 95.84%of the total inputs,respectively.In contrast,TN,TP and fluoride inputs in Ulansuhai Lake were 53.56%,40.98%,and 36.25%,respectively.This indicates that the pollutant inputs associated with LGD posed a potential threat to the ecological stability of Daihai and Ulansuhai Lake.By comparison,the differences of LGD process and associated pollutant flux were controlled by hydrogeological conditions,lakebed permeability and human activities.This study provides a reference for water resources management in Daihai and Ulansuhai Lake basins while improving the understanding of LGD in the Yellow River basin.
基金supported bythe Foundation of Science and Technology Program of Guangdong Province,China(No.2008A030201021)the Natural Science Foundation of Guangdong Province,China(No.10151001002000010)
文摘Objective Category-specific recognition and naming deficits have been observed in a variety of patient populations. However, the category-specific cortices for naming famous faces, animals and man-made objects remain controversial. The present study aimed to study the specific areas involved in naming pictures of these 3 categories using functional magnetic resonance imaging. Methods Functional images were analyzed using statistical parametric mapping and the 3 different contrasts were evaluated using t statistics by comparing the naming tasks to their baselines.The contrast images were entered into a random-effects group level analysis.The results were reported in Montreal Neurological Institute co-ordinates,and anatomical regions were identified using an automated anatomical labeling method with XJview 8.Results Naming famous faces caused more activation in the bilateral head of the hippocampus and amygdala with significant left dominance. Bilateral activation of pars triangularis and pars opercularis in the naming of famous faces was also revealed. Naming animals evoked greater responses in the left supplementary motor area, while naming man-made objects evoked more in the left premotor area,left pars orbitalis and right supplementary motor area. The extent of bilateral fusiform gyri activation by naming man-made objects was much larger than that by naming of famous faces or animals.Even in the overlapping sites of activation,some differences among the categories were found for activation in the fusiform gyri.Conclusion The cortices involved in the naming process vary with the naming of famous faces,animals and man-made objects.This finding suggests that different categories of pictures should be used during intra-operative language mapping to generate a broader map of language function, in order to minimize the incidence of false-negative stimulation and permanent post-operative deficits.
基金support of Spea Ingegneria Europea SpA and Società Autostrade per l’Italia SpA
文摘This paper describes the interaction between deep-seated landslides and man-made structures such as dams, penstocks, viaducts, and tunnels. Selected case studies are reported first with the intent to gain insights into the complexities associated with the interaction of these structures with deep-seated landslides(generally referred to as deep-seated gravity slope deformations, DSGSDs). The main features, which characterize these landslides, are mentioned together with the interaction problems encountered in each case. Given the main objective of this paper, the numerical modeling methods adopted are outlined as means for increase in the understanding of the interaction problems being investigated. With the above in mind, the attention moves to an important and unique case history dealing with the interaction of a large-size twin-tunnel excavated with an earth pressure balance(EPB)tunnel boring machine(TBM) and a deep-seated landslide, which was reactivated due to the stress changes induced by tunnel excavation in landslide shear zone. The geological and geotechnical conditions are described together with the available monitoring data on the landslide movements, based on the advanced and conventional monitoring tools used. Numerical modeling is illustrated as an aid to back-analyze the monitored surface and subsurface deformations and to assist in finding the appropriate engineering solution for putting the tunnel into service and as a follow-up means for future understanding and control of the interaction problems. The simulation is based on a novel time-dependent model representing the landslide behavior.
基金co-supported by the National Natural Science Foundation of China (61473148)the Funding of Jiangsu Innovation Program for Graduate Education (No. KYLX16_0337)
文摘Man-made object detection is of great significance in both military and civil areas, such as search-and-rescue missions at sea, traffic signs recognition during visual navigation, and targets location in a military strike. Contours of man-made objects usually consist of straight lines, corner points, and simple curves. Motivated by this observation, a man-made object detection method is proposed based on complexity evaluation of object contours. After salient contours which keep the crucial information of objects are accurately extracted using an improved mean-shift clustering algorithm, a novel approach is presented to evaluate the complexity of contours. By comparing the entropy values of contours before/after sampling and linear interpolation, it is easy to distinguish between man-made objects and natural ones according to the complexity of their contours.Experimental results show that the presented method can effectively detect man-made objects when compared to the existing ones.
文摘In this study the regeneration diversity of Syahkal forests afforestated and natural stands in north of Iran was studied and compared from the point of view of evenness and diversity index. In order to accomplish this study two natural and man-made stands that almost are located in the same height above the sea level were chosen. The area of each stand was 30 ha and the inventory was done by the random-systematic method with a 5R land measurement (500 m2) selected. Also, in order to study the regeneration in the center of each sample piece 125 square meters micro plots were formed. The results show that regeneration diversity index in natural stands is more than that in man-made stands which in this case Mc-Arthur index with 2.41 has the most amount while Simpson index with 0.543 has the least amount. But the evenness indexes in man-made stands are more than that in natural stand which the main reason is the purity of the man-made stand.
基金This study was supported by the National Natural Science Foundation of China(U20A20148)the Major Science and Technology Projects of the Xizang(Tibet)Autonomous Region(XZ202201ZD0004G and XZ202201ZD0004G01).
文摘This research optimized the structure of lithium extraction solar ponds to enhance the crystallization rate and yield of Li_(2)CO_(3).Using the response surface methodology in Design-Expert 10.0.3,the authors conducted experiments to investigate the influence of four factors related to solar pond structure on the crystallization of Li_(2)CO_(3) and their pairwise interactions.Computational Fluid Dynamics(CFD)simulations of the flow field within the solar pond were performed using COMSOL Multiphysics software to compare temperature distributions before and after optimization.The results indicate that the optimal structure for lithium extraction from the Zabuye Salt Lake solar ponds includes UCZ(Upper Convective Zone)thickness of 53.63 cm,an LCZ(Lower Convective Zone)direct heating temperature of 57.39℃,a CO32−concentration of 32.21 g/L,and an added soda ash concentration of 6.52 g/L.Following this optimized pathway,the Li_(2)CO_(3) precipitation increased by 7.34% compared to the initial solar pond process,with a 33.33% improvement in lithium carbonate crystallization rate.This study demonstrates the feasibility of optimizing lithium extraction solar pond structures,offering a new approach for constructing such ponds in salt lakes.It provides valuable guidance for the efficient extraction of lithium resources from carbonate-type salt lake brines.
基金The Joint Research Project for Yangtze River Conservation,No.2022-LHYJ-02-0504-05-08Anhui Provincial Scientific Research Project for Universities,China No.2023AH050508。
文摘To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test,box plots,and violin plots.The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes,with an average water level of 12.82 m and a monthly range of 11.21–17.24m.Since 2017,the water level of Huayang Rivers has shown a decreasing trend of–0.02 m/a.Total phosphorus(TP)has become the primary pollutant.The TP concentrations in Longgan Lake(the largest lake)during the dry,rising,flood,and retreating seasons from 2015 to 2023were 0.083,0.061,0.050,and 0.059 mg/L,respectively.The effect of water level on TP was mainly observed during the low-water period.When the water level in the dry season rose to 12.25 and 13.00 m,the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8%and 33.3%,respectively.During the dry season,wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes.This led to drastic fluctuations in TP concentration,reducing the correlation between water level and TP.When external control is limited,the water level during the dry season should be maintained between 12.25 and 13.0 m.Additionally,it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans)in the Huayang Rivers.
文摘The 25th China International Man-made Fiber Conference (Bengbu 2019)(hereinafter referred to as CIMFC 2019), themed on “Opening and Integaration for Interactive Development — Coordinated Progress of Global Man-Made Fiber Industry”, was convened in Bengbu City, Anhui Province. CIMFC 2019 was sponcored by China National Textile and Apparel Council (CNTAC), organized by China Chemical Fibers Association, Chi-na Textile International Exchange Center, and China BBCA Group Corp., supported by Bengbu Municipal People’s Goverment, and co-organized by Bengbu Investment Promotion and Foreign cooperation Center, Bengbu Municipal Bureau of Commerce and Foreign Affairs, and Oerlikon Man-made Fiber.
基金supported by the National Key Research and Development Program(2022YFC3202104)National Natural Science Foundation of China(32101237)Natural Science Foundation of Jiangsu Province(BK20211151)。
文摘The behavioral responses of birds to urban environments are crucial for their ability to thrive within city landscapes.Various urban birds have demonstrated the capacity to exploit artificial structures as nesting sites due to the limited availability of natural options.This review examines the current state of urban bird nesting behaviors on manmade structures and highlights directions for future research.Nest types frequently observed on these structures include woven,cavity,ground,and mud nests.These adaptive behaviors increase nesting opportunities and improve reproductive success,although they may heighten vulnerability to ecological traps.Proximity to human habitats can promote conservation awareness but also presents potential economic and health-related challenges.Therefore,applying diverse strategies is essential for effectively managing and protecting nests on man-made structures across various circumstances.There is also a need for thorough,long-term studies on the ecological and evolutionary impacts of nest building on artificial structures and the mechanisms influencing nestsite selection.Furthermore,exploring innovative approaches that combine policy implementation and citizen science will be vital for advancing human-bird coexistence.
基金Supported by the National Natural Science Foundation of China(Nos.42007397,41871073)the Natural Science Foundation of Shandong Province(No.ZR2020QD002)。
文摘Decades of species composition changes can lead to the eutrophication-driven loss of submerged macrophytes in shallow lakes.Investigating the mechanisms of these nature-and human driven changes is crucial for the restoration and management of such lakes.To investigate the changes in aquatic macrophyte communities over the past two centuries,we analyzed macrofossils in sediments from a^(210)Pb-dated core obtained in Dongping Lake in the lower Huanghe(Yellow)River Basin,eastern China.Multiple factor analysis(MFA)revealed an association between macrophyte shifts and changes in various environmental stressors(invertebrates,grain size,geochemistry,and documented records),indicating that macrophyte community changes before 1960 were predominately driven by flood disturbances.Ever since,anthropogenic pollution and the construction of water conservancy projects have caused variations in hydrology and nutrients,leading to significant changes in the composition of macrophyte communities.Macrofossil data reveal a decline in diversity and pollution-intolerant species during the late 1980 s and the early 2000 s,which is indicative of eutrophication.We also found that the current environment of Dongping Lake exhibits a clear degeneration in emergent plants and a proliferation of macrophyte species associated with eutrophic conditions,which could be attributed to water level fluctuation and nutrient input due to the water supply from the eastern route of the South-to-North Water Diversion Project as well as climate warming.Our results provide valuable insights for assessing ecosystem health and the restoration and management of Dongping Lake and similar lakes in the Huanghe River region and elsewhere.
文摘As an important fundamental industry of the national economy,the man-made fiber industrial chain is integrated into the era development and it assumes the responsibility of advancing.Each link of the industrial chain is connected with each other.After the development and accumulation of several decades,the new produced polyester,PTA and other plants keep