[Objective] The effect of baffled surface flow wetlands on water purification was studied in order to provide a reference for the ecological restoration of polluted river.[Method] Contents of some indexes like DO,TN,T...[Objective] The effect of baffled surface flow wetlands on water purification was studied in order to provide a reference for the ecological restoration of polluted river.[Method] Contents of some indexes like DO,TN,TP,NH+4-N,CODCr,SS,SD,etc.were determined in the band baffled surface flow wetlands with total area of 7 400 m2 at JiaLu riverside.[Result] Baffled surface flow wetlands could improve the effluent quality significantly,could enhance transparency and dissolved oxygen content and also could decrease SS content.The removal rate of TN was kept at more than 73% in summer and decreased to 23% in early winter;The removal rate of TP was little influenced by temperature,and it was kept at more than 77% in summer and still kept at more than 69% in autumn and winter;The removal rate of NH+4-N was kept at more than 83% in summer and decreased slightly in autumn and winter,but still kept at more than 75%;The removal rate of CODCr ranged from 14% to 50%.[Conclusion] Baffled surface flow wetlands could effectively improve the purification effect of surface flow wetlands,which is a feasible way for ecological restoration.展开更多
With the accelerating development of modern residential districts and the improvement of living levels, the requirement of people on environment is increasingly enhanced as well as the demand for culture. Based on peo...With the accelerating development of modern residential districts and the improvement of living levels, the requirement of people on environment is increasingly enhanced as well as the demand for culture. Based on people-oriented principle, this design utilized Chinese 'Fu' (blessings) culture to express people’s eager for a better life and the atmosphere of good fortune. It also produced the image of ecological environment by designing water landscapes and plant landscapes, created active space like squares for activity and active water system and developed the characteristics of residential districts by designing landscape sketches and plant landscapes.展开更多
By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were ...By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.展开更多
In order to explore the nitrogen removal process in constructed wetlands(CW s),the moisture,ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3"-N)and nitrification intensity in three wetland plant rhizosphere soils(Ac...In order to explore the nitrogen removal process in constructed wetlands(CW s),the moisture,ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3"-N)and nitrification intensity in three wetland plant rhizosphere soils(Acorns calamus,Typha orientalis,Iris pseudacorus)were investigated at a relatively normal temperature range of15to25The relative abundance of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)were also achieved using fluorescence in situ hybridization(FISH).It is found that T.orientalis achieves the highest nitrification intensity of2.03m g(h?kg)while the second is I.pseudacorrs(1.74m g/(h?kg)),and followed by A.calamus(1.65m g/(h?kg))throughout the experiment.FISH reveals that the abundance of bacteria(1010g_1wet soil)is higher than that of archaea(109g_1wet soil),and AOBare the dominant bacteria in the ammonia oxidation process.The abundance of AOB in te rhizosphere soils from high to low T.orientalis(1.88x1010g"1),I pseudacorus(1.23x1010g1),A.calamus(5.07x109g"1)while the abundance of AOA from high to low ae I.pseudacorus(4.00x109g1),A.calamus(3.52x109g"1),T.orientalis(3.48x109g"1).The study provides valuable evidence of plant selection for nitrogen removal in CWs.展开更多
Distribution patterns of plant species are believed to be impacted by small-scale habitat heterogeneity. However, there have been few comparative studies examining how woody vegetation composition and diversity varies...Distribution patterns of plant species are believed to be impacted by small-scale habitat heterogeneity. However, there have been few comparative studies examining how woody vegetation composition and diversity varies with aspects of different orientations in the Trans-Himalayan region at a local scale. Here, we examined the effects of incoming solar radiation on variation in woody species composition and compared the diversity between the northeast- and southwest-facing slopes in a Trans-Himalayan valley of Nepal. We also examined the implicit interactions between slope orientation and land use in determining the compositional variations between the slopes. We selected two pairs of northeast- and southwest-facing slopes where the first pair has a similar land use and differs in exposure only(Pisang site) while the other pair has clear differences in land use in addition to slope exposure(Braka site). In each site, we sampled 72 plots(36 on each slope) in which the presence and absence of woody species, environmental variables, and disturbance were recorded. Correspondence Analysis(CA) results suggested that the woody species composition significantly varied between northeast- and southwest-facing slopes at both sites, and was significantly correlated with measured environmental variables such as radiation index, altitude, and canopy openness. In the Braka site,mean alpha diversity was significantly higher on southwest-facing slopes. In contrast, beta diversity and gamma diversity were greater on northeast-facing slopes at both sites. Our results suggest that topographic variables(e.g., radiation index) affect species composition between the slopes, likely due to their influence on small scale abiotic environmental variables. However, the effects of land use, such as livestock browsing/grazing may interact with the effects of slope exposure, effectively reducing differences in species composition within slopes but enhancing the differences in beta diversity between contrasting slopes in the Braka. We conclude that slope orientation and land use are important factors in structuring the woody species composition and diversity in the arid Trans-Himalayan region. We suggest that both environmental and land use variables should be taken into consideration in future studies on plant community structure along the cultural landscapes.展开更多
This study investigated the impact of topography and vegetation on distribution of rare earth elements(REEs)in calcareous soils using methods of single extraction and mass balance calculation. The purposes of the stud...This study investigated the impact of topography and vegetation on distribution of rare earth elements(REEs)in calcareous soils using methods of single extraction and mass balance calculation. The purposes of the study were to set a basis for further research on the biogeochemical REE cycle and to provide references for soil–water conservation and REE-containing fertilizer amendments. The results show a generally flat Post-Archean Average Australian Shale—normalized REE pattern for the studied calcareous soils. REE enrichment varied widely. The proportion of acidsoluble phases of heavy REEs was higher than that of light REEs. From top to bottom of the studied hills, dominant REE sources transitioned from limestone in-situ weathering to input from REE-containing phases(e.g., clay minerals,amorphous iron, REE-containing fluids). Our results indicate that the REE content of calcareous soils is mainly controlled by slope aspect, while the enrichment degree of REEs is related to geomorphological position and vegetation type.Furthermore, the proportion of acid-soluble phases of REEs is mainly controlled by geomorphological position.展开更多
In China, the environmental education (EE) is a brief new but popular topic in recent several years as a method to cope with the gap between nature and children. EE was started in UK with a long-term development and...In China, the environmental education (EE) is a brief new but popular topic in recent several years as a method to cope with the gap between nature and children. EE was started in UK with a long-term development and the useful experience can be utilized for the Chinese EE development. As a case study, the experiences of UK organizations were summarized and applied in the EE system in Fairy Lake Botanical Garden in Shenzhen (SZBG), China. The localization of UK’s experience in the EE development in SZBG in terms of EE program, course content and resource was summarized in this paper. There are also discussions for the future update of EE in SZBG and for other local organizations like botanical gardens, wetland parks, nature reserve etc.展开更多
The Middle Jurassic Hangfanggou Formation is well exposed in Shangsanjiao and Xiasanjiao villages area,Baimashi town of Huludao,western Liaoning,China.Recently,abundant fossil plants were collected from the Hangfanggo...The Middle Jurassic Hangfanggou Formation is well exposed in Shangsanjiao and Xiasanjiao villages area,Baimashi town of Huludao,western Liaoning,China.Recently,abundant fossil plants were collected from the Hangfanggou Formation.One new species,Anomozamites sanjiaocunensis sp.nov.(Bennettitales),is described in this study.This is the first report of the genus Anomozamites from the Haifanggou Formation based upon the leaf morphology and epidermal structures.The discovery of the new species extends significantly the stratigraphic and geographic distribution of Anomozamites in the Middle Jurassic.It also shows that Anomozamites was a common member of Bennettitales once lived in the Middle Jurassic warm temperate region.The new species also improves the knowledge on understanding the leaf morphology,epidermal features and the diversity of Anomozamites during the Middle Jurassic.The epidermal characters of the new species and its associated plants reveal that the plants grew in a warm and moderately humid environment in the warm temperate zone.The presence of some deciduous plants,such as ginkgoaleans,czekanowskialeans and conifers,indicate the climate with seasonal fluctuations in temperature.展开更多
A participatory breeding on Arabica coffee involving farmers and plant breeders to select superior local varieties has been conducted at Lintong highland (North Sumatra), Gayo highland (Central Aceh, Northern Suma...A participatory breeding on Arabica coffee involving farmers and plant breeders to select superior local varieties has been conducted at Lintong highland (North Sumatra), Gayo highland (Central Aceh, Northern Sumatra) and Kendenan Plateau (Enrekang, South Sulawesi). The aim of using this method was to find out superior varieties of Arabica coffee having appropriate specific traits and adaptable to such locations and accelerating the process of variety adoption by local farmers. Selection process was initiated by the farmer(s) based on high yielding performance by using their native experiences. The next step was conducted by plant breeder in collaboration with coffee farmers and other relevant scientists to evaluate more detail of cup quality, resistance to leaf rust and/or parasitic nematode as well as yielding potential and agronomic traits at different farmer's sites for several years observations. Research finding showed that three selected varieties namely Sigarar Utang, Gayo 1 and Gayo 2 had already been released by Minister of Agriculture for commercial planting at North Sumatera and Gayo highland. They performed excellent cup profile with high yielding ability (more than 1 t/ha) and tolerant to leaf rust disease. Therefore, it could support origin specialty coffee product at Gayo and Lintong highlands. However, observation over of selected local variety at Kendenan Plateau namely Salongge variety performed lower yielding ability (below 1 t/ha) and less stable yield over years as well as more heterogenous population in their offsprings than that of existing released varieties planted at the same location. Therefore, it could not be released as local varieties which adapted to specific location.展开更多
In Western culture, the symbol of the tree which divides into branches and has a foliage of the same lineage as its roots is the best symbol for describing identity and also for describing the Cartesian reasoning whic...In Western culture, the symbol of the tree which divides into branches and has a foliage of the same lineage as its roots is the best symbol for describing identity and also for describing the Cartesian reasoning which proceeds by eliminating misconceptions and following thesingle true idea. In the West Indies culture, it is the rhizome that is the best symbol to describe the identity of these peoples. The rhizome as explained by Deleuze and Gattari in their Introduction Rhizome of the book .4 thousand plateaus, is a tuber that makes roots after being cut off from its original plant. In this respect, it is most appropriate to describe the people of the Caribbean who have been cut off from their African roots by slavery but who have thrived on the island, re-establishing links with the different peoples who came to work there. The rhizome is similar to the mangrove that protects the island from marine erosion, it intertwines with other plants so that it is impossible to distinguish the source plant. In this respect, it is the best symbol to describe the creole identity and the refusal of the West Indians to return to a racial and social system that promulgated the white race as superior to the black race during colonialism. The structure of the books of Maryse Cond6 is itself rhizomatic since it does not present the theme of its stories through the view point of an omnipotent author but through the view points of all the characters of the novel who by their discussions letthe reader discover their terrible history of slavery, and transform himinto a new man who would seek diversity.展开更多
Research on selection of superior breeding infraspecies Gyrinops versteegii (Gilg) Domke aims to select an infraspecies of G. versteegii having internal factors that affect the quality and quantity of production aro...Research on selection of superior breeding infraspecies Gyrinops versteegii (Gilg) Domke aims to select an infraspecies of G. versteegii having internal factors that affect the quality and quantity of production aromatic resin or agarwood. The internal factors are variations in wood anatomy, phytochemicals and agarwood of infraspecies G. versteegii. Of five local populations taken from West Lombok Island in Indonesia, the research areas are geographically located at coordinates: 8°15′-8°40′ South Latitude and 116°00′-116°20′East Longitude. Quality and quantity of agarwood production is influenced by internal factors of eaglewood trees, such as high starch production and the size of the cells making up the larger wood tissue. Infraspecies G. versteegii that have quality and quantity production of aromatic resin (the best agarwood) is Beringin group and the highest quantity of agarwood production (agarwood formation on the whole organ) is Soyun group.展开更多
Biological invasions by alien and range-expanding native plant species can suppress native plants through allelopathy.However,the homeland security hypothesis suggests that some native plants can resist invasion by pr...Biological invasions by alien and range-expanding native plant species can suppress native plants through allelopathy.However,the homeland security hypothesis suggests that some native plants can resist invasion by producing allelopathic compounds that inhibit the growth of invasive plants.Most research has focused on allelopathic interactions between individual native and invasive plant species,with less emphasis on how allelopathy helps entire native communities resist invasions.Additionally,limited knowledge exists about allelopathic interactions between range-expanding native species and recipient native communities,and their influence on invasion success.To bridge this knowledge gap,we conducted two greenhouse competition experiments to test reciprocal allelopathic effects between a native woody range-expanding species,Betula fruticosa,and a community of four native herbaceous species(Sanguisorba officinalis,Gentiana manshurica,Sium suave and Deyeuxia angustifolia)in China.We assessed whether B.fruticosa and the native community differed in their competitive effects and responses,and whether these were influenced by activated carbon,which neutralizes allelochemicals in the soil.Activated carbon reduced the suppressive effects of the native community on the above-ground biomass of B.fruticosa,which indicates that the native community exerted a strong allelopathic effect on B.fruticosa.In contrast,activated carbon only marginally enhanced the suppressive effects of B.fruticosa on the native community,which indicates that allelopathy is not the primary mechanism by which B.fruticosa exerts its suppression.Overall,these findings support the homeland security hypothesis and suggest that biotic resistance from the native herbaceous community may limit the invasion success of the woody range-expander B.fruticosa.展开更多
Although biotic and abiotic factors have been confirmed to be critical factors that affect community dynamics,their interactive effects have yet to be fully considered in grassland degradation.Herein,we tested how soi...Although biotic and abiotic factors have been confirmed to be critical factors that affect community dynamics,their interactive effects have yet to be fully considered in grassland degradation.Herein,we tested how soil nutrients and microbes regulated plant-soil feedback(PSF)in a degraded alpine grassland.Our results indicated that soil total carbon(STC;from 17.66 to 12.55 g/kg)and total nitrogen(STN;from 3.16 to 2.74 g/kg)exhibited significant(P<0.05)decrease from non-degraded(ND)to severely degraded(SD).Despite higher nutrients in ND soil generating significantly(P<0.05)positive PSF(0.52)on monocots growth when the soil was sterilized,a high proportion of pathogens(36%)in ND non-sterilized soil resulted in a strong negative PSF on monocots.In contrast,the higher phenotypic plasticity of dicots coupled with a higher abundance of mutualists and saprophytes(70%)strongly promoted their survival and growth in SD with infertile soil.Our findings identified a novel mechanism that there was a functional group shift from monocots with higher vulnerability to soil pathogens in the ND fertile soil to dicots with higher dependence on nutritional mutualists in the degraded infertile soil.The emerging irreversible eco-evolutionary in PSF after degradation might cause a predicament for the restoration of degraded grassland.展开更多
Quantitative reconstructions of atmospheric CO2 by using terrestrial and marine records are critical for understanding the so-called "greenhouse" conditions in the Cretaceous, but data from terrestrial plants for se...Quantitative reconstructions of atmospheric CO2 by using terrestrial and marine records are critical for understanding the so-called "greenhouse" conditions in the Cretaceous, but data from terrestrial plants for several stages of this period remain quite limited. Using the stomatal index (SI) technique, here we estimate the Santonian (Late Cretaceous) CO2 contents based on a sequence of fossil cuticles of Ginkgo adiantoides (Ung.) Heer from three beds of the Yong'ancun Formation in Jiayin, Heilongjiang Province, northeastern China. By the regress function, Sis of Ginkgo fossils reveal a pronounced CO2 reduction from the early to late Santonian (-661 and -565 ppm, respectively). The relatively high CO2 levels provide additional evidence for paleoclimatic warmth in this interval. Moreover, available paleobotanical data illustrate a decline trend of CO2 contents throughout the Late Cretaceous, punctuated by several fluctuations in particular episodes with different magnitudes. The CO2 contents shifted notably in the late Cenomanian, Turonian, early Santonian, late Campanian, and probably latest Maastrichtian. Furthermore, a comprehensive study based on CO2 data shows that the global mean land surface temperature (GMLST) fluctuated several times accordingly. The change ratios of GMLST (AT) increased from -3℃ in late Cenomanian to -4.7℃ in mid Turonian, and then dramatically reduced to -2.2℃ in mid Coniacian. From the Santonian onward, it appears that the temperature gradually decreased with a few minor fluctuations.展开更多
Global changes have altered the distribution pattern of the plant communities,including invasive species.Anthropogenic contamination may reduce native plant resistance to the invasive species.Thus,the focus of the cur...Global changes have altered the distribution pattern of the plant communities,including invasive species.Anthropogenic contamination may reduce native plant resistance to the invasive species.Thus,the focus of the current review is on the contaminant biogeochemical behavior among native plants,invasive species and the soil within the plant-soil ecosystem to improve our understanding of the interactions between invasive plants and environmental stressors.Our studies together with synthesis of the literature showed that(i)the impacts of invasive species on environmental stress were heterogeneous,(ii)the size of the impact was variable and(iii)the influence types were multidirectional even within the same impact type.However,invasive plants showed self-protective mechanisms when exposed to heavy metals(HMs)and provided either positive or negative influence on the bioavailability and toxicity of HMs.On the other hand,HMs may favor plant invasion due to the widespread higher tolerance of invasive plants to HMs together with the‘escape behavior’of native plants when exposed to toxic HM pollution.However,there has been no consensus on whether elemental compositions of invasive plants are different from the natives in the polluted regions.A quantitative research comparing plant,litter and soil contaminant contents between native plants and the invaders in a global context is an indispensable research focus in the future.展开更多
Aims Morphological variation of leaves is a key indicator of plant response to climatic change.Leaf size and shape are associated with carbon,water and energy exchange of plants with their environment.However,whether ...Aims Morphological variation of leaves is a key indicator of plant response to climatic change.Leaf size and shape are associated with carbon,water and energy exchange of plants with their environment.However,whether and how leaf size and shape responded to climate change over the past decades remains poorly studied.Moreover,many studies have only explored inter-but not intraspecific variation in leaf size and shape across space and time.Methods We collected>6000 herbarium specimens spanning 98 years(1910–2008)in China for seven representative dicot species and measured their leaf length and width.We explored geographical patterns and temporal trends in leaf size(i.e.leaf length,leaf width and length×width product)and shape(i.e.length/width ratio),and investigated the effects of changes in precipitation and temperature over time and space on the variation in leaf size and shape.Important Findings After accounting for the effects of sampling time,leaf size decreased with latitude for all species combined,but the relationship varied among species.Leaf size and shape were positively correlated with temperature and precipitation across space.After accounting for the effects of sampling locations,leaf size of all species combined increased with time.Leaf size changes over time were mostly positively correlated with precipitation,whereas leaf shape changes were mostly correlated with temperature.Overall,our results indicate significant spatial and temporal intraspecific variation in leaf size and shape in response to climate.Our study also demonstrates that herbarium specimens collected over a considerable period of time provide a good resource to study the impacts of climate change on plant morphological traits.展开更多
The increase in atmospheric nitrogen(N)deposition has profound effects on soil respiration(SR).However,the responses of SR to the addition of different N compounds,particularly in saline-alkaline grasslands remain unc...The increase in atmospheric nitrogen(N)deposition has profound effects on soil respiration(SR).However,the responses of SR to the addition of different N compounds,particularly in saline-alkaline grasslands remain unclear.A 3-year controlled field experiment was conducted to investigate the responses of SR to different N compounds(NH,NO,(NH),SO,and NH,HCO,)during the growing seasons in a saline-alkaline grassland located in the agro-pastoral ecotone of northern China.Our results demonstrated that SR showed a bimodal pattern and a significant interannual diference that was regulated by air or soil temperature and precipitation.Nitrogen addition had a significant effect on SR,and the effect of N addition on SR varied yearly,which was related to seasonal precipitation.The mean SR across 3 years(2017-2019)was increased by 19.9%,13.0%and 16.6%with the addition of NH,NO,(NH,),SO,and NH,HCO3,respectively.The highest effect of NH,NO3 addition on SR across 3 years was ascribed to the highest aboveground net primary production,belowground net primary production(BNPP)and soil NO,-concentrations.SR(C loss)was significantly increased while plant productivity(C input)did not significantly change under NH,HCO,addition,indicating a decrease in C sequestration.In addition,BNPP was the main direct factor influencing SR in this saline-alkaline grassland,and soil salinization(e.g.soil base cations and pH)indirectly affected SR through soil microorganisms.Notably,NH,NO,addition overestimated the response of SR to N addition,and different N compounds should be considered,especially in saline-alkaline grassland.展开更多
Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the ...Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the most significant horizons for the Jurassic petrified wood in Liaoning Province. Previously, wood fossils of this formation were mainly reported in Beipiao and Chaoyang regions, whereas fossil wood record was merely known in Jianchang region. Here we describe new fossil wood specimens from the Tiaojishan Formation in Jianchang County, western Liaoning. Two fossil wood taxa, i.e., Protaxodioxylon jianchangense Tian et Wang sp. nov. and Xenoxylon peidense Zheng et Zhang were recognized on the basis of anatomical features. These fossil wood records add new data for understanding the fossil wood diversity, floral composition and palaeoclimate of the Tiaojishan Formation. The occurrence of Xenoxylon and Protaxodioxylon implies a cool temperate, wet and seasonal climate condition with interannual variations during the Middle to Late Jurassic transition in western Liaoning region.展开更多
Changes in soil chemistry after invasion by bracken(Pteridium aquilinum)have been studied in heathlands,but comparable studies in meadows are lacking.We investigated if bracken invasion into P-deficient meadows alters...Changes in soil chemistry after invasion by bracken(Pteridium aquilinum)have been studied in heathlands,but comparable studies in meadows are lacking.We investigated if bracken invasion into P-deficient meadows alters the soil nutrient-resource pool,as well as the mechanisms behind it linked to soil processes and bracken nutrition.Furthermore,we investigated how community composition responds to differences in soil chemistry before and after the invasion.Soil and plant material sampling,along with vegetation survey,were performed during bracken peak biomass.Data analyses included analysis of variance and canonical correspondence analysis(CCA).Bracken invasion increased soil P availability,soil organic C concentration,as well as C:N,C:S and N:S ratios,while decreasing Fe and Co concentrations.Bracken pinnae were rich in P,and its rhizomes were rich in K,whereas N:P of pinnae and rhizomes was low.CCA showed contrasting abundance patterns of frequent meadow species related to P and K availability.Holcus lanatus exhibited competitive advantage under extremely low P availability.Increase in P availability under bracken may have occurred through promoting the leaching of Fe and Al.By increasing P availability for its growth and increasing N limitation for other species,bracken can gain a competitive advantage from the soil resource-niche perspective.Its ability to increase soil P availability,along with the physiological mechanisms behind its high P acquisition efficiency,seem to differentiate bracken from other species of competitive ecological strategy,which are mainly confined to nutrient-rich environments.This enabled bracken to invade P-deficient meadows.展开更多
基金Supported by Deep Purification Technology Project of Mixed Mode Wetland for Sewage Plant Waster Water in Dryland(2006AA6Z325)~~
文摘[Objective] The effect of baffled surface flow wetlands on water purification was studied in order to provide a reference for the ecological restoration of polluted river.[Method] Contents of some indexes like DO,TN,TP,NH+4-N,CODCr,SS,SD,etc.were determined in the band baffled surface flow wetlands with total area of 7 400 m2 at JiaLu riverside.[Result] Baffled surface flow wetlands could improve the effluent quality significantly,could enhance transparency and dissolved oxygen content and also could decrease SS content.The removal rate of TN was kept at more than 73% in summer and decreased to 23% in early winter;The removal rate of TP was little influenced by temperature,and it was kept at more than 77% in summer and still kept at more than 69% in autumn and winter;The removal rate of NH+4-N was kept at more than 83% in summer and decreased slightly in autumn and winter,but still kept at more than 75%;The removal rate of CODCr ranged from 14% to 50%.[Conclusion] Baffled surface flow wetlands could effectively improve the purification effect of surface flow wetlands,which is a feasible way for ecological restoration.
文摘With the accelerating development of modern residential districts and the improvement of living levels, the requirement of people on environment is increasingly enhanced as well as the demand for culture. Based on people-oriented principle, this design utilized Chinese 'Fu' (blessings) culture to express people’s eager for a better life and the atmosphere of good fortune. It also produced the image of ecological environment by designing water landscapes and plant landscapes, created active space like squares for activity and active water system and developed the characteristics of residential districts by designing landscape sketches and plant landscapes.
基金Supported by Natural Science Foundation of Shanghai(10ZR1400300 )Central University Special Foundation of Basic Research and Operating expenses+1 种基金Creative Group Foundation of the National Natural Science Foundation of China (50721006)Key Discipline construction Project of Shanghai (B604)~~
文摘By measuring wetland plants chlorophyll content,malondialdehyde(MDA) content and superoxide dismutase(SOD) enzyme activity,the changes of wetland plant physiological characeristics under different power strength were studied,and the mechanism of electric field on plant physiological characteristics was analyzed to provide a theoretical basis for the pollutant removal ability strengthening of artificial wetland under electricfield.The results showed that compared with the control plants,low-intensity-voltage(1 V and 3 V) had no significant effect on the normal physiological and biochemical indexes of the plants,and the growth trend was better than the control group;with the voltage increasing,plant chlorophyll content,MDA content and SOD activity were greatly affected,indicating that plants were under strong oxidative stress,and the growth was damaged.Therefore,a suitable electric field could enhance the sewage treatment effect of constructed wetland.
基金The National Natural Science Foundation of China(No.51479034,50909019)the Fundamental Research Funds for the Central Universities
文摘In order to explore the nitrogen removal process in constructed wetlands(CW s),the moisture,ammonia nitrogen(NH4+-N),nitrate nitrogen(NO3"-N)and nitrification intensity in three wetland plant rhizosphere soils(Acorns calamus,Typha orientalis,Iris pseudacorus)were investigated at a relatively normal temperature range of15to25The relative abundance of ammonia-oxidizing bacteria(AOB)and ammonia-oxidizing archaea(AOA)were also achieved using fluorescence in situ hybridization(FISH).It is found that T.orientalis achieves the highest nitrification intensity of2.03m g(h?kg)while the second is I.pseudacorrs(1.74m g/(h?kg)),and followed by A.calamus(1.65m g/(h?kg))throughout the experiment.FISH reveals that the abundance of bacteria(1010g_1wet soil)is higher than that of archaea(109g_1wet soil),and AOBare the dominant bacteria in the ammonia oxidation process.The abundance of AOB in te rhizosphere soils from high to low T.orientalis(1.88x1010g"1),I pseudacorus(1.23x1010g1),A.calamus(5.07x109g"1)while the abundance of AOA from high to low ae I.pseudacorus(4.00x109g1),A.calamus(3.52x109g"1),T.orientalis(3.48x109g"1).The study provides valuable evidence of plant selection for nitrogen removal in CWs.
基金Annapurna Conservation Area Project (ACAP)Norwegian State Educational Loan Fund (Lnekassen)+2 种基金Faculty of Mathematics and Natural Sciences,University of Bergen for financingfunded by Norwegian Research Council(project no.148910/730)supported by The Norwegian Council for Higher Education Programme for Development Research and Education(NUFU Project ID:PRO 04/2002)
文摘Distribution patterns of plant species are believed to be impacted by small-scale habitat heterogeneity. However, there have been few comparative studies examining how woody vegetation composition and diversity varies with aspects of different orientations in the Trans-Himalayan region at a local scale. Here, we examined the effects of incoming solar radiation on variation in woody species composition and compared the diversity between the northeast- and southwest-facing slopes in a Trans-Himalayan valley of Nepal. We also examined the implicit interactions between slope orientation and land use in determining the compositional variations between the slopes. We selected two pairs of northeast- and southwest-facing slopes where the first pair has a similar land use and differs in exposure only(Pisang site) while the other pair has clear differences in land use in addition to slope exposure(Braka site). In each site, we sampled 72 plots(36 on each slope) in which the presence and absence of woody species, environmental variables, and disturbance were recorded. Correspondence Analysis(CA) results suggested that the woody species composition significantly varied between northeast- and southwest-facing slopes at both sites, and was significantly correlated with measured environmental variables such as radiation index, altitude, and canopy openness. In the Braka site,mean alpha diversity was significantly higher on southwest-facing slopes. In contrast, beta diversity and gamma diversity were greater on northeast-facing slopes at both sites. Our results suggest that topographic variables(e.g., radiation index) affect species composition between the slopes, likely due to their influence on small scale abiotic environmental variables. However, the effects of land use, such as livestock browsing/grazing may interact with the effects of slope exposure, effectively reducing differences in species composition within slopes but enhancing the differences in beta diversity between contrasting slopes in the Braka. We conclude that slope orientation and land use are important factors in structuring the woody species composition and diversity in the arid Trans-Himalayan region. We suggest that both environmental and land use variables should be taken into consideration in future studies on plant community structure along the cultural landscapes.
基金supported jointly by the National Natural Science Foundation of China(41571130042,41522207,41325010)the State’s Key Project of Research and Development Plan of China(2016YFA0601002)
文摘This study investigated the impact of topography and vegetation on distribution of rare earth elements(REEs)in calcareous soils using methods of single extraction and mass balance calculation. The purposes of the study were to set a basis for further research on the biogeochemical REE cycle and to provide references for soil–water conservation and REE-containing fertilizer amendments. The results show a generally flat Post-Archean Average Australian Shale—normalized REE pattern for the studied calcareous soils. REE enrichment varied widely. The proportion of acidsoluble phases of heavy REEs was higher than that of light REEs. From top to bottom of the studied hills, dominant REE sources transitioned from limestone in-situ weathering to input from REE-containing phases(e.g., clay minerals,amorphous iron, REE-containing fluids). Our results indicate that the REE content of calcareous soils is mainly controlled by slope aspect, while the enrichment degree of REEs is related to geomorphological position and vegetation type.Furthermore, the proportion of acid-soluble phases of REEs is mainly controlled by geomorphological position.
文摘In China, the environmental education (EE) is a brief new but popular topic in recent several years as a method to cope with the gap between nature and children. EE was started in UK with a long-term development and the useful experience can be utilized for the Chinese EE development. As a case study, the experiences of UK organizations were summarized and applied in the EE system in Fairy Lake Botanical Garden in Shenzhen (SZBG), China. The localization of UK’s experience in the EE development in SZBG in terms of EE program, course content and resource was summarized in this paper. There are also discussions for the future update of EE in SZBG and for other local organizations like botanical gardens, wetland parks, nature reserve etc.
基金supported by China Geological Survey Grant (12120111201491212011085275 )+2 种基金National Natural Science Foundation of China (41172009 )Specialized Research Fund for the Doctoral Program of Higher Education grant (2010061110034)Project "111" of China
文摘The Middle Jurassic Hangfanggou Formation is well exposed in Shangsanjiao and Xiasanjiao villages area,Baimashi town of Huludao,western Liaoning,China.Recently,abundant fossil plants were collected from the Hangfanggou Formation.One new species,Anomozamites sanjiaocunensis sp.nov.(Bennettitales),is described in this study.This is the first report of the genus Anomozamites from the Haifanggou Formation based upon the leaf morphology and epidermal structures.The discovery of the new species extends significantly the stratigraphic and geographic distribution of Anomozamites in the Middle Jurassic.It also shows that Anomozamites was a common member of Bennettitales once lived in the Middle Jurassic warm temperate region.The new species also improves the knowledge on understanding the leaf morphology,epidermal features and the diversity of Anomozamites during the Middle Jurassic.The epidermal characters of the new species and its associated plants reveal that the plants grew in a warm and moderately humid environment in the warm temperate zone.The presence of some deciduous plants,such as ginkgoaleans,czekanowskialeans and conifers,indicate the climate with seasonal fluctuations in temperature.
文摘A participatory breeding on Arabica coffee involving farmers and plant breeders to select superior local varieties has been conducted at Lintong highland (North Sumatra), Gayo highland (Central Aceh, Northern Sumatra) and Kendenan Plateau (Enrekang, South Sulawesi). The aim of using this method was to find out superior varieties of Arabica coffee having appropriate specific traits and adaptable to such locations and accelerating the process of variety adoption by local farmers. Selection process was initiated by the farmer(s) based on high yielding performance by using their native experiences. The next step was conducted by plant breeder in collaboration with coffee farmers and other relevant scientists to evaluate more detail of cup quality, resistance to leaf rust and/or parasitic nematode as well as yielding potential and agronomic traits at different farmer's sites for several years observations. Research finding showed that three selected varieties namely Sigarar Utang, Gayo 1 and Gayo 2 had already been released by Minister of Agriculture for commercial planting at North Sumatera and Gayo highland. They performed excellent cup profile with high yielding ability (more than 1 t/ha) and tolerant to leaf rust disease. Therefore, it could support origin specialty coffee product at Gayo and Lintong highlands. However, observation over of selected local variety at Kendenan Plateau namely Salongge variety performed lower yielding ability (below 1 t/ha) and less stable yield over years as well as more heterogenous population in their offsprings than that of existing released varieties planted at the same location. Therefore, it could not be released as local varieties which adapted to specific location.
文摘In Western culture, the symbol of the tree which divides into branches and has a foliage of the same lineage as its roots is the best symbol for describing identity and also for describing the Cartesian reasoning which proceeds by eliminating misconceptions and following thesingle true idea. In the West Indies culture, it is the rhizome that is the best symbol to describe the identity of these peoples. The rhizome as explained by Deleuze and Gattari in their Introduction Rhizome of the book .4 thousand plateaus, is a tuber that makes roots after being cut off from its original plant. In this respect, it is most appropriate to describe the people of the Caribbean who have been cut off from their African roots by slavery but who have thrived on the island, re-establishing links with the different peoples who came to work there. The rhizome is similar to the mangrove that protects the island from marine erosion, it intertwines with other plants so that it is impossible to distinguish the source plant. In this respect, it is the best symbol to describe the creole identity and the refusal of the West Indians to return to a racial and social system that promulgated the white race as superior to the black race during colonialism. The structure of the books of Maryse Cond6 is itself rhizomatic since it does not present the theme of its stories through the view point of an omnipotent author but through the view points of all the characters of the novel who by their discussions letthe reader discover their terrible history of slavery, and transform himinto a new man who would seek diversity.
文摘Research on selection of superior breeding infraspecies Gyrinops versteegii (Gilg) Domke aims to select an infraspecies of G. versteegii having internal factors that affect the quality and quantity of production aromatic resin or agarwood. The internal factors are variations in wood anatomy, phytochemicals and agarwood of infraspecies G. versteegii. Of five local populations taken from West Lombok Island in Indonesia, the research areas are geographically located at coordinates: 8°15′-8°40′ South Latitude and 116°00′-116°20′East Longitude. Quality and quantity of agarwood production is influenced by internal factors of eaglewood trees, such as high starch production and the size of the cells making up the larger wood tissue. Infraspecies G. versteegii that have quality and quantity production of aromatic resin (the best agarwood) is Beringin group and the highest quantity of agarwood production (agarwood formation on the whole organ) is Soyun group.
基金supported by the National Natural Science Foundation of China(NSFC:41901054)the Chinese Academy of Sciences(CAS-PIFI:2021VBB0004).
文摘Biological invasions by alien and range-expanding native plant species can suppress native plants through allelopathy.However,the homeland security hypothesis suggests that some native plants can resist invasion by producing allelopathic compounds that inhibit the growth of invasive plants.Most research has focused on allelopathic interactions between individual native and invasive plant species,with less emphasis on how allelopathy helps entire native communities resist invasions.Additionally,limited knowledge exists about allelopathic interactions between range-expanding native species and recipient native communities,and their influence on invasion success.To bridge this knowledge gap,we conducted two greenhouse competition experiments to test reciprocal allelopathic effects between a native woody range-expanding species,Betula fruticosa,and a community of four native herbaceous species(Sanguisorba officinalis,Gentiana manshurica,Sium suave and Deyeuxia angustifolia)in China.We assessed whether B.fruticosa and the native community differed in their competitive effects and responses,and whether these were influenced by activated carbon,which neutralizes allelochemicals in the soil.Activated carbon reduced the suppressive effects of the native community on the above-ground biomass of B.fruticosa,which indicates that the native community exerted a strong allelopathic effect on B.fruticosa.In contrast,activated carbon only marginally enhanced the suppressive effects of B.fruticosa on the native community,which indicates that allelopathy is not the primary mechanism by which B.fruticosa exerts its suppression.Overall,these findings support the homeland security hypothesis and suggest that biotic resistance from the native herbaceous community may limit the invasion success of the woody range-expander B.fruticosa.
基金supported by the National Key R&D Program of China(2023YFF1304304)the National Natural Science Foundation of China(31870406 and 42301071)+1 种基金the China Postdoctoral Science Foundation(2023M743633)the Science and Technology Major Project of Tibetan Autonomous Region of China(XZ202201ZD0005G02).
文摘Although biotic and abiotic factors have been confirmed to be critical factors that affect community dynamics,their interactive effects have yet to be fully considered in grassland degradation.Herein,we tested how soil nutrients and microbes regulated plant-soil feedback(PSF)in a degraded alpine grassland.Our results indicated that soil total carbon(STC;from 17.66 to 12.55 g/kg)and total nitrogen(STN;from 3.16 to 2.74 g/kg)exhibited significant(P<0.05)decrease from non-degraded(ND)to severely degraded(SD).Despite higher nutrients in ND soil generating significantly(P<0.05)positive PSF(0.52)on monocots growth when the soil was sterilized,a high proportion of pathogens(36%)in ND non-sterilized soil resulted in a strong negative PSF on monocots.In contrast,the higher phenotypic plasticity of dicots coupled with a higher abundance of mutualists and saprophytes(70%)strongly promoted their survival and growth in SD with infertile soil.Our findings identified a novel mechanism that there was a functional group shift from monocots with higher vulnerability to soil pathogens in the ND fertile soil to dicots with higher dependence on nutritional mutualists in the degraded infertile soil.The emerging irreversible eco-evolutionary in PSF after degradation might cause a predicament for the restoration of degraded grassland.
基金supported by the National Basic Research Pro-gram of China (Grant No. 2006CB701401)the National Natural Science Foundation of China (Grant No. 41002004)+1 种基金China Postdoctoral Science Foundation (Grant No. 20090451258)the Fund of LPS, Nanjing Insti-tute of Geology and Palaeontology, CAS (Grant No. 103107)
文摘Quantitative reconstructions of atmospheric CO2 by using terrestrial and marine records are critical for understanding the so-called "greenhouse" conditions in the Cretaceous, but data from terrestrial plants for several stages of this period remain quite limited. Using the stomatal index (SI) technique, here we estimate the Santonian (Late Cretaceous) CO2 contents based on a sequence of fossil cuticles of Ginkgo adiantoides (Ung.) Heer from three beds of the Yong'ancun Formation in Jiayin, Heilongjiang Province, northeastern China. By the regress function, Sis of Ginkgo fossils reveal a pronounced CO2 reduction from the early to late Santonian (-661 and -565 ppm, respectively). The relatively high CO2 levels provide additional evidence for paleoclimatic warmth in this interval. Moreover, available paleobotanical data illustrate a decline trend of CO2 contents throughout the Late Cretaceous, punctuated by several fluctuations in particular episodes with different magnitudes. The CO2 contents shifted notably in the late Cenomanian, Turonian, early Santonian, late Campanian, and probably latest Maastrichtian. Furthermore, a comprehensive study based on CO2 data shows that the global mean land surface temperature (GMLST) fluctuated several times accordingly. The change ratios of GMLST (AT) increased from -3℃ in late Cenomanian to -4.7℃ in mid Turonian, and then dramatically reduced to -2.2℃ in mid Coniacian. From the Santonian onward, it appears that the temperature gradually decreased with a few minor fluctuations.
基金supported by the National Natural Science Foundation of China(32071521,31800429)the Natural Science Foundation of Jiangsu Province(BK20170540)Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment,China.
文摘Global changes have altered the distribution pattern of the plant communities,including invasive species.Anthropogenic contamination may reduce native plant resistance to the invasive species.Thus,the focus of the current review is on the contaminant biogeochemical behavior among native plants,invasive species and the soil within the plant-soil ecosystem to improve our understanding of the interactions between invasive plants and environmental stressors.Our studies together with synthesis of the literature showed that(i)the impacts of invasive species on environmental stress were heterogeneous,(ii)the size of the impact was variable and(iii)the influence types were multidirectional even within the same impact type.However,invasive plants showed self-protective mechanisms when exposed to heavy metals(HMs)and provided either positive or negative influence on the bioavailability and toxicity of HMs.On the other hand,HMs may favor plant invasion due to the widespread higher tolerance of invasive plants to HMs together with the‘escape behavior’of native plants when exposed to toxic HM pollution.However,there has been no consensus on whether elemental compositions of invasive plants are different from the natives in the polluted regions.A quantitative research comparing plant,litter and soil contaminant contents between native plants and the invaders in a global context is an indispensable research focus in the future.
基金supported by the National Key Research Development Program of China(grant number 2018YFA0606104)National Natural Science Foundation of China(grant numbers 31988102,31911530102,and Chinese Academy of Sciences-Peking University Pioneer Collaboration Team.
文摘Aims Morphological variation of leaves is a key indicator of plant response to climatic change.Leaf size and shape are associated with carbon,water and energy exchange of plants with their environment.However,whether and how leaf size and shape responded to climate change over the past decades remains poorly studied.Moreover,many studies have only explored inter-but not intraspecific variation in leaf size and shape across space and time.Methods We collected>6000 herbarium specimens spanning 98 years(1910–2008)in China for seven representative dicot species and measured their leaf length and width.We explored geographical patterns and temporal trends in leaf size(i.e.leaf length,leaf width and length×width product)and shape(i.e.length/width ratio),and investigated the effects of changes in precipitation and temperature over time and space on the variation in leaf size and shape.Important Findings After accounting for the effects of sampling time,leaf size decreased with latitude for all species combined,but the relationship varied among species.Leaf size and shape were positively correlated with temperature and precipitation across space.After accounting for the effects of sampling locations,leaf size of all species combined increased with time.Leaf size changes over time were mostly positively correlated with precipitation,whereas leaf shape changes were mostly correlated with temperature.Overall,our results indicate significant spatial and temporal intraspecific variation in leaf size and shape in response to climate.Our study also demonstrates that herbarium specimens collected over a considerable period of time provide a good resource to study the impacts of climate change on plant morphological traits.
基金This work Was supported by Chinese National Key Research and Development Program for Basic Research(2017YFA0604802)the National Natural Science Foundation of China(31770526,31872406and 31800402)the Research projects of Shanxi Province's doctoral graduates and postdoctoral researchers working in Shanxi Province(SXBYKY2021052).
文摘The increase in atmospheric nitrogen(N)deposition has profound effects on soil respiration(SR).However,the responses of SR to the addition of different N compounds,particularly in saline-alkaline grasslands remain unclear.A 3-year controlled field experiment was conducted to investigate the responses of SR to different N compounds(NH,NO,(NH),SO,and NH,HCO,)during the growing seasons in a saline-alkaline grassland located in the agro-pastoral ecotone of northern China.Our results demonstrated that SR showed a bimodal pattern and a significant interannual diference that was regulated by air or soil temperature and precipitation.Nitrogen addition had a significant effect on SR,and the effect of N addition on SR varied yearly,which was related to seasonal precipitation.The mean SR across 3 years(2017-2019)was increased by 19.9%,13.0%and 16.6%with the addition of NH,NO,(NH,),SO,and NH,HCO3,respectively.The highest effect of NH,NO3 addition on SR across 3 years was ascribed to the highest aboveground net primary production,belowground net primary production(BNPP)and soil NO,-concentrations.SR(C loss)was significantly increased while plant productivity(C input)did not significantly change under NH,HCO,addition,indicating a decrease in C sequestration.In addition,BNPP was the main direct factor influencing SR in this saline-alkaline grassland,and soil salinization(e.g.soil base cations and pH)indirectly affected SR through soil microorganisms.Notably,NH,NO,addition overestimated the response of SR to N addition,and different N compounds should be considered,especially in saline-alkaline grassland.
基金jointly supported by the State Key Program of Basic Research of Ministry of Science and TechnologyChina(Grant No.2012CB822003)+10 种基金the National Natural Science Foundation of China(Grant Nos.412720104130200441172026&41402004)the Team Program of Scientific Innovation and Interdisciplinary Cooperation of CASthe Natural Science Foundation(Grant No.201102199)Education Bureau Foundation(Grant No.LR2012038)of Liaoning Province\the State Key Laboratory of Palaeobiology and Stratigraphy(NIGPASCAS)(Grant No.133113)Science Research Project of Liaoning Provincial Education Department(Grant No.L2012391)the Talent Fund of Shenyang Normal University(Grant No.91400114006)the Provincial Training Programs of Innovation and Entrepreneurship for Undergraduates of Liaoning(Grant No.201310166058)
文摘Diverse and rich fossil wood records have been documented from the Mesozoic of Liaoning Province, NE China. The Tiaojishan Formation(mainly distributed in Beipiao, Chaoyang, Fuxin and Jianchang regions) is one of the most significant horizons for the Jurassic petrified wood in Liaoning Province. Previously, wood fossils of this formation were mainly reported in Beipiao and Chaoyang regions, whereas fossil wood record was merely known in Jianchang region. Here we describe new fossil wood specimens from the Tiaojishan Formation in Jianchang County, western Liaoning. Two fossil wood taxa, i.e., Protaxodioxylon jianchangense Tian et Wang sp. nov. and Xenoxylon peidense Zheng et Zhang were recognized on the basis of anatomical features. These fossil wood records add new data for understanding the fossil wood diversity, floral composition and palaeoclimate of the Tiaojishan Formation. The occurrence of Xenoxylon and Protaxodioxylon implies a cool temperate, wet and seasonal climate condition with interannual variations during the Middle to Late Jurassic transition in western Liaoning region.
文摘Changes in soil chemistry after invasion by bracken(Pteridium aquilinum)have been studied in heathlands,but comparable studies in meadows are lacking.We investigated if bracken invasion into P-deficient meadows alters the soil nutrient-resource pool,as well as the mechanisms behind it linked to soil processes and bracken nutrition.Furthermore,we investigated how community composition responds to differences in soil chemistry before and after the invasion.Soil and plant material sampling,along with vegetation survey,were performed during bracken peak biomass.Data analyses included analysis of variance and canonical correspondence analysis(CCA).Bracken invasion increased soil P availability,soil organic C concentration,as well as C:N,C:S and N:S ratios,while decreasing Fe and Co concentrations.Bracken pinnae were rich in P,and its rhizomes were rich in K,whereas N:P of pinnae and rhizomes was low.CCA showed contrasting abundance patterns of frequent meadow species related to P and K availability.Holcus lanatus exhibited competitive advantage under extremely low P availability.Increase in P availability under bracken may have occurred through promoting the leaching of Fe and Al.By increasing P availability for its growth and increasing N limitation for other species,bracken can gain a competitive advantage from the soil resource-niche perspective.Its ability to increase soil P availability,along with the physiological mechanisms behind its high P acquisition efficiency,seem to differentiate bracken from other species of competitive ecological strategy,which are mainly confined to nutrient-rich environments.This enabled bracken to invade P-deficient meadows.