Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and...Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the ecoenvironment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108m^3/a, the surface water resources are 1891×10^8m^3/a, the total natural groundwater resources are 1150×10^8m^3/a, the total available water resources are 438×10^8 m^3/a, and the total water resources are 1996×10^8m^3/a and per capita water resources are 2278 m^3/a. The water resources of the whole area are 5.94×10^4m^3/(a.km^2), being only one-fifth of the mean value in China. Now, the available water resources are 876×10^8m^3/a, among which groundwater is proximate 130×10^8m^3/a.展开更多
According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method i...According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method is used to standardize the selected indices,and Principal Component Analysis is applied by using year as a unit.FB is obtained,which is related with the ecological safety of land-use change from 1999 to 2008.According to the scientific,integrative,hierarchical,practical and dynamic principles,ecological safety evaluation index system of land-use change in Ji'an City is established.Principal Component Analysis and evaluation model are used to calculate four parameters,including the natural resources safety index of land use,the socio-economic safety indicators of land use,the eco-environmental safety index of land use,and the ecological safety degree of land use in Ji'an City.Result indicates that the ecological safety degree of land use in Ji'an City shows a slow upward trend as a whole.At the same time,ecological safety degree of land-use change is relatively low in Ji'an City with the safety value of 0.645,which is at a weak safety zone and needs further monitoring and maintenance.展开更多
The Nine plateau lakes are those lakes whose areas are larger than 30km2 in Yunnan province.These lakes are Dianchi Lake,Erhai Lake,Fuxian Lake,Chenghai Lake,Lugu Lake,Qilu Lake,Xingyun Lake,Yangzonghai Lake,and Yilon...The Nine plateau lakes are those lakes whose areas are larger than 30km2 in Yunnan province.These lakes are Dianchi Lake,Erhai Lake,Fuxian Lake,Chenghai Lake,Lugu Lake,Qilu Lake,Xingyun Lake,Yangzonghai Lake,and Yilong Lake.The nine plateau lakes are important for economic development and for ecological security.However,all lakes are facing different environmental issues such as eutrophication and water quality degradation.Different strategies should be proposed according to the various conditions of the lakes.Three types of prevention,control and treatment strategies were proposed based on the succession process,the ecology stages,the economic and social development,the eutrophication stages,the water qualities,and the dominant ecological functions.展开更多
Gas hydrates-the firm crystal connections formed water(water,ice,water vapor)and low-molecular waterproof natural gases(mainly methane)whose crystal structure effectively compresses gas:each cubic meter of hydrate can...Gas hydrates-the firm crystal connections formed water(water,ice,water vapor)and low-molecular waterproof natural gases(mainly methane)whose crystal structure effectively compresses gas:each cubic meter of hydrate can yield over 160 m3 of methane.In present time exploitation of the Messoyahsk(Russia)and Mallik(Canada)deposits of gas hydrates in is conducted actively.The further perfection of prospecting methods in the field of studying gas hydrates containing sediments in round extent depends on improvement of geophysical and well test research,among which native-state core drilling is one of the major.Sampling native-state core from gas hydrates sediments keeping not only original composition,but structural-textural features of their construction.Despite of appeal of use gas hydrates as the perspective and ecologically pure fuel possessing huge resources,investigation and development of their deposits can lead to a number of the negative consequences connected with arising hazards for maintenance of their technical and ecological safety of carrying out.Scales of arising problems can change from local up to regional and even global.展开更多
[Objective] This study aimed to investigate the frequency of exogenous gene flow to non-transgenic conventional rice cultivars and assess the potential risks of marker-free of insect-resistant transgenic rice to agric...[Objective] This study aimed to investigate the frequency of exogenous gene flow to non-transgenic conventional rice cultivars and assess the potential risks of marker-free of insect-resistant transgenic rice to agricultural ecological environment. [Method] Insect-resistant transgenic rice variety HUAHUI No.1 was planted as the experimental material and surrounded by several non-transgenic conventional rice cultivars. F1 non-transgenic rice seeds were collected according to different distances and identified by using PCR technology, the frequency of exogenous gene flow from insect-resistant transgenic rice to non-transgenic conventional rice cultivars was counted and analyzed. [Result] The average frequency of exogenous Bt gene flow to P13381 and CHUNJIANG063 was 0. Transgene flow occurred to varying degrees from insect-resistant transgenic rice HUAHUI No.1 to several non-transgenic rice lines including HEX122-2, TIANXlANG, MINGHUI63 and Pl157, with the maximum average gene flow frequency of 0.875%. The frequency of gene flow was gradually reduced with the increase of distance, and the average transgene flow frequency de- creased to 0 in all the sampling points 7 m away from transgenic rice material. [Conclusion] This study revealed that the exogenous gene flow frequency of insect-re- sistant transgenic rice variety HUAHUI No.1 was very low, leading to very small risk to the eco-environment. Rational distribution in the field for physical isolation, keeping the appropriate distance and scientific farming arrangement to avoid the synchronization of flowering can effectively control the exogenous gene flow from transgenic rice and reduce he ecological risks caused by transgene escape.展开更多
Acetochlor and methamidophos are two important agrochemicals which are widely applied to agricultural production in northeast China. The investigation on the earthworm Eisenia fetida as an important type of soil anima...Acetochlor and methamidophos are two important agrochemicals which are widely applied to agricultural production in northeast China. The investigation on the earthworm Eisenia fetida as an important type of soil animals exposed to single and binary-combined contamination of acetochlor and methamidophos was thus carried out. The single toxic effect test showed that the two agrochemicals had their toxicity to the earthworms living in phaiozem. Acetochlor had a stronger acute toxic effect on the earthworms than methamidophos. The mortality of the earthworms exposed to individual acetochlor and methamidophos changed with an increase in the exposure time and the exposed concentrations. The LD50 value of acetochlor and methamidophos toxic to the earthworms was 115.6-275,3 and 29.5-228.6 mg/kg, respectively. The weight of the earthworms was a more sensitive index compared to the mortality in indicating toxic effects of acetochlor and methamidophos in phaiozem. When considering both the mortality and the body-weight change, the combined pollution of acetochlor and methamidophos in phaiozem resulted in their synergic toxic effects on the earthworms.展开更多
The sources of marine oil spills are mainly from accidents of marine oil tankers or freighters, marine oil-drilling platforms, marine oil pipelines, marine oilfields, terrestrial pollution, oil-bearing atmosphere, and...The sources of marine oil spills are mainly from accidents of marine oil tankers or freighters, marine oil-drilling platforms, marine oil pipelines, marine oilfields, terrestrial pollution, oil-bearing atmosphere, and offshore oil production equipment. It is concluded upon analysis that there are two main reasons for marine oil spills: (I) The motive for huge economic benefits of oil industry owners and oil shipping agents far surpasses their sense of ecological risks. (II) Marine ecological safety has not become the main concern of national security. Oil spills are disasters because humans spare no efforts to get economic benefits from oil. The present paper draws another conclusion that marine ecological damage caused by oil spills can be roughly divided into two categories: damage to marine resource value (direct value) and damage to marine ecosystem service value (indirect value). Marine oil spills cause damage to marine biological, fishery, seawater, tourism and mineral resources to various extents, which contributes to the lower quality and value of marine resources.展开更多
[Objective] The research aimed to calculate and analyze ecological footprint of the urban agglomeration in Pearl River Delta in 2009. [Method] 9 cities in Pearl River Delta as research zone, by using calculation model...[Objective] The research aimed to calculate and analyze ecological footprint of the urban agglomeration in Pearl River Delta in 2009. [Method] 9 cities in Pearl River Delta as research zone, by using calculation model of the ecological footprint, ecological footprint and security of the urban agglomeration in Pearl River Delta were calculated. Current situation and sustainable development condition of the ecological environment in Pearl River Delta were conducted quantitative analysis. [Result] Except construction land and woodland, other 4 kinds of lands were all in ecological deficit states in Pearl River Delta. Especially arable land and fossil fuel land had obvious ecological deficit. [Conclusion] Biological resource consumption level and energy consumption level in Pearl River Delta were higher. We ought to take a variety of measures to reduce ecological deficit, making development manner turn toward sustainable direction.展开更多
The genetic manipulation of agriculturally important insects now allows the development of genetic sexing and male sterility systems for more highly efficient biologically-based population control programs, most notab...The genetic manipulation of agriculturally important insects now allows the development of genetic sexing and male sterility systems for more highly efficient biologically-based population control programs, most notably the Sterile Insect Technique (SIT), for both plant and animal insect pests. Tetracycline-suppressible (Tet-off) conditional lethal systems may function together so that transgenic strains will be viable and fertile on a tetracycline-containing diet, but female-lethal and male sterile in tetracycline-free condi- tions. This would allow their most efficacious use in a unified system for sterile male-only production for SIT. A critical consideration for the field release of such transgenic insect strains, however, is a determination of the frequency and genetic basis of lethality revertant survival. This will provide knowledge essential to evaluating the genetic stability of the lethality system, its environmental safety, and provide the basis for modifications ensur- ing optimal efficacy. For Tet-off lethal survival determinations, development of large-scale screening protocols should also allow the testing of these modifications, and test the ability of other conditional lethal systems to fully suppress propagation of rare Tet-off survivors. If a dominant temperature sensitive (DTS) pupal lethality system proves efficient for sec- ondary lethality in Drosophila, it may provide the safeguard needed to support the release of sexing/sterility strains, and potentially, the release of unisex lethality strains as a form of genetic male sterility. Should the DTS Prosβ21 mutation prove effective for redundant lethality, its high level of structural and functional conservation should allow host-specific cognates to be created for a wide range of insect species.展开更多
The problem of land ecological security directly threatens the sustainable development of many regions,and exploring the spatio-temporal characteristics of land ecological security is helpful for analyzing the land ec...The problem of land ecological security directly threatens the sustainable development of many regions,and exploring the spatio-temporal characteristics of land ecological security is helpful for analyzing the land ecological patterns between regions and over time.Based on the interpretation of remote sensing image data for Tianjin in 1980,2000,2010 and 2019,supported by software such as ArcGIS and GeoDa,the changes of land use in the study area are calculated by using the land use dynamic degree.Then,the land ecological security index and spatial autocorrelation analysis methods are used to study the spatial correlations and internal heterogeneity of land ecological security in each district in Tianjin.The results show that:(1)The land use of Tianjin has changed dramatically in the past 40 years:the building land has been expanding,while the farmland and barren have been shrinking continuously.(2)The overall level of land ecological security is in the high security area,and Jizhou District is the highest,while the Central areas and Binhai are low.(3)The spatial heterogeneity of land ecological security is not obvious,but the spatial agglomeration is strong.展开更多
Currently,the wastewater treatment plants(WWTPs)attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants discharge.However,they have not been able to satisfy th...Currently,the wastewater treatment plants(WWTPs)attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants discharge.However,they have not been able to satisfy the increasing ecological safety needs.In this study,the removal of micropollutants was investigated,and the ecological safety was assessed for a local WWTP.Although the total concentration of 31 micropollutants detected was reduced by 83%using the traditional biological treatment processes,the results did not reflect chemicals that had poor removal efficiencies and low concentrations.Of the five categories of micropollutants,herbicides,insecticides,and bactericides were difficult to remove,pharmaceuticals and UV filters were effectively eliminated.The specific photosynthesis inhibition effect and non-specific bioluminescence inhibition effect from wastewater were detected and evaluated using hazardous concentration where 5%of aquatic organisms are affected.The photosynthesis inhibition effect from wastewater in the WWTP was negligible,even the untreated raw wastewater.However,the bioluminescence inhibition effect from wastewater which was defined as the priority biological effect,posed potential ecological risk.To decrease non-specific biological effects,especially of macromolecular dissolved organic matter,overall pollutant reduction strategy is necessary.Meanwhile,the ozonation process was used to further decrease the bioluminescence inhibition effects from the secondary effluent;≥0.34 g O 3/g DOC of ozone dose was recommended for micropollutants elimination control and ecological safety.展开更多
Ecological safety is a major consideration in the commercialization of transgenic fish. Development of sterile transgenic triploid fish through hybridization of transgenic tetraploid fish and transgenic diploid fish i...Ecological safety is a major consideration in the commercialization of transgenic fish. Development of sterile transgenic triploid fish through hybridization of transgenic tetraploid fish and transgenic diploid fish is a feasible way to solve this problem. The "all-fish" transgene, pbcAbcGHc, containing the black carp β-actin gene promoter and the open reading frame (ORF) of the black carp growth hormone (GH) gene was constructed and introduced into fertilized eggs of allotetraploid fish through microinjection. Contrast cultivation results showed that the growth rate of 150 day-old P 0 black carp GH gene transgenic allotetraploid fish was much higher than that of controls. Sixty 150 day-old transgenic allotetraploid fish were assayed by PCR for transgene integration and 90% of fish were positive for the transgene. The transgene was detected in 13 of 20 sperm samples from male transgenic allotetraploid fish. RT-PCR detected transcription of the exogenous black carp GH gene in the muscle, liver, kidney and ovaries of the largest transgenic allotetraploid fish. This study has developed P 0 black carp GH gene transgenic allotetraploid fish with a highly increased growth rate, which provides a solid foundation for the establishment of a pure line of transgenic allotetraploid fish and for the large scale production of sterile transgenic triploid fish.展开更多
Polyaluminum chloride modified clay(PAC-MC)is a safe and efficient red tide control agent that has been studied and applied worldwide.Although it is well known that the distribution of hydrolytic aluminum species in P...Polyaluminum chloride modified clay(PAC-MC)is a safe and efficient red tide control agent that has been studied and applied worldwide.Although it is well known that the distribution of hydrolytic aluminum species in PAC affects its flocculation,little is known about the influence of particulars aluminum species on the microalgae removal efficiency of PAC-MC;this lack of knowledge creates a bottleneck in the development of more efficient MCs based on aluminum salts.The ferron method was used in this study to quantitatively analyze the distributions of and variations in different hydrolytic aluminum species during the process of microalgae removal by PAC-MC.The results showed that Ala,which made up 5%–20%of the total aluminum,and Alp,which made up 15%–55%of the total aluminum,significantly affected microalgae removal,with Pearson’s correlation coefficients of 0.83 and 0.89,respectively.Most of the aluminum in the PAC-MC sank rapidly into the sediments,but the rate and velocity of settlement were affected by the dose of modified clay.The optimal dose of PAC-MC for precipitating microalgae was determined based on its aluminum profile.These results provide guidance for the precise application of PAC-MC in the control of harmful algal blooms.展开更多
In recent years, the quantity and quality of global forest resources are declining continually. Contrarily, the both in China are increasing, which is deeply related to the sustainable forest management and eco-system...In recent years, the quantity and quality of global forest resources are declining continually. Contrarily, the both in China are increasing, which is deeply related to the sustainable forest management and eco-system management in China. With the trend that world community knows more about the important role of forest, more and more functions of forest are recognized. The impact and functions of China's forestry deserve more concern. Based on some experiences in the field of forestry research, the authors introduced and analyzed the key role of China's forestry for the sustainable development, and explained the functions of China's forestry, such as ensuring ecological safety, addressing climate change, improving economic development, promoting social harmony and prospering ecological culture.展开更多
基金National Natural Science Foundation of China, No.40235053 No.40401012+1 种基金 AIACC, No.AS25 Lanzhou Jiaotong University Foundation
文摘Northwest China includes Xinjiang Ugyur Autonomous Region, Qinghai Province, Gansu Province, Ningxia Hui Autonomous Region and Shaanxi Province, covering 308×10^4km^2. It is located in the warm-temperate zone and the climate is arid or semi-arid. Precipitation is very scarce but evaporation is extremely high. The climate is dry, the water resources are deficient, the ecoenvironment is fragile, and the distribution of water resources is uneven. In this region, precipitation is the only input, and evaporation is the only output in the inland rivers, and precipitation, surface water and groundwater change with each other for many times, which benefits the storage and utilization of water resources. The average precipitation in this region is 232 mm, the total precipitation amount is 7003×108m^3/a, the surface water resources are 1891×10^8m^3/a, the total natural groundwater resources are 1150×10^8m^3/a, the total available water resources are 438×10^8 m^3/a, and the total water resources are 1996×10^8m^3/a and per capita water resources are 2278 m^3/a. The water resources of the whole area are 5.94×10^4m^3/(a.km^2), being only one-fifth of the mean value in China. Now, the available water resources are 876×10^8m^3/a, among which groundwater is proximate 130×10^8m^3/a.
基金Supported by Major Project of Chinese National Programs for Fundamental Research and Development Program(2009CB219401)Key Project of Natural Science Foundation of China(40534019)
文摘According to the ecological safety evaluation index data of land-use change in Ji'an City from 1999 to 2008,positive treatment on selected reverse indices is conducted by Reciprocal Method.Meanwhile,Index Method is used to standardize the selected indices,and Principal Component Analysis is applied by using year as a unit.FB is obtained,which is related with the ecological safety of land-use change from 1999 to 2008.According to the scientific,integrative,hierarchical,practical and dynamic principles,ecological safety evaluation index system of land-use change in Ji'an City is established.Principal Component Analysis and evaluation model are used to calculate four parameters,including the natural resources safety index of land use,the socio-economic safety indicators of land use,the eco-environmental safety index of land use,and the ecological safety degree of land use in Ji'an City.Result indicates that the ecological safety degree of land use in Ji'an City shows a slow upward trend as a whole.At the same time,ecological safety degree of land-use change is relatively low in Ji'an City with the safety value of 0.645,which is at a weak safety zone and needs further monitoring and maintenance.
文摘The Nine plateau lakes are those lakes whose areas are larger than 30km2 in Yunnan province.These lakes are Dianchi Lake,Erhai Lake,Fuxian Lake,Chenghai Lake,Lugu Lake,Qilu Lake,Xingyun Lake,Yangzonghai Lake,and Yilong Lake.The nine plateau lakes are important for economic development and for ecological security.However,all lakes are facing different environmental issues such as eutrophication and water quality degradation.Different strategies should be proposed according to the various conditions of the lakes.Three types of prevention,control and treatment strategies were proposed based on the succession process,the ecology stages,the economic and social development,the eutrophication stages,the water qualities,and the dominant ecological functions.
文摘Gas hydrates-the firm crystal connections formed water(water,ice,water vapor)and low-molecular waterproof natural gases(mainly methane)whose crystal structure effectively compresses gas:each cubic meter of hydrate can yield over 160 m3 of methane.In present time exploitation of the Messoyahsk(Russia)and Mallik(Canada)deposits of gas hydrates in is conducted actively.The further perfection of prospecting methods in the field of studying gas hydrates containing sediments in round extent depends on improvement of geophysical and well test research,among which native-state core drilling is one of the major.Sampling native-state core from gas hydrates sediments keeping not only original composition,but structural-textural features of their construction.Despite of appeal of use gas hydrates as the perspective and ecologically pure fuel possessing huge resources,investigation and development of their deposits can lead to a number of the negative consequences connected with arising hazards for maintenance of their technical and ecological safety of carrying out.Scales of arising problems can change from local up to regional and even global.
基金Supported by Project of Common Safety Assessment Technology for Genetically Modified Organisms of the Ministry of Agriculture of PRC(2011ZX08011-006)Project of Protection and Utilization of Agricultural Biological Resources"Intrusion Detection of Alien Species"~~
文摘[Objective] This study aimed to investigate the frequency of exogenous gene flow to non-transgenic conventional rice cultivars and assess the potential risks of marker-free of insect-resistant transgenic rice to agricultural ecological environment. [Method] Insect-resistant transgenic rice variety HUAHUI No.1 was planted as the experimental material and surrounded by several non-transgenic conventional rice cultivars. F1 non-transgenic rice seeds were collected according to different distances and identified by using PCR technology, the frequency of exogenous gene flow from insect-resistant transgenic rice to non-transgenic conventional rice cultivars was counted and analyzed. [Result] The average frequency of exogenous Bt gene flow to P13381 and CHUNJIANG063 was 0. Transgene flow occurred to varying degrees from insect-resistant transgenic rice HUAHUI No.1 to several non-transgenic rice lines including HEX122-2, TIANXlANG, MINGHUI63 and Pl157, with the maximum average gene flow frequency of 0.875%. The frequency of gene flow was gradually reduced with the increase of distance, and the average transgene flow frequency de- creased to 0 in all the sampling points 7 m away from transgenic rice material. [Conclusion] This study revealed that the exogenous gene flow frequency of insect-re- sistant transgenic rice variety HUAHUI No.1 was very low, leading to very small risk to the eco-environment. Rational distribution in the field for physical isolation, keeping the appropriate distance and scientific farming arrangement to avoid the synchronization of flowering can effectively control the exogenous gene flow from transgenic rice and reduce he ecological risks caused by transgene escape.
文摘Acetochlor and methamidophos are two important agrochemicals which are widely applied to agricultural production in northeast China. The investigation on the earthworm Eisenia fetida as an important type of soil animals exposed to single and binary-combined contamination of acetochlor and methamidophos was thus carried out. The single toxic effect test showed that the two agrochemicals had their toxicity to the earthworms living in phaiozem. Acetochlor had a stronger acute toxic effect on the earthworms than methamidophos. The mortality of the earthworms exposed to individual acetochlor and methamidophos changed with an increase in the exposure time and the exposed concentrations. The LD50 value of acetochlor and methamidophos toxic to the earthworms was 115.6-275,3 and 29.5-228.6 mg/kg, respectively. The weight of the earthworms was a more sensitive index compared to the mortality in indicating toxic effects of acetochlor and methamidophos in phaiozem. When considering both the mortality and the body-weight change, the combined pollution of acetochlor and methamidophos in phaiozem resulted in their synergic toxic effects on the earthworms.
基金supported by the Academy of Ocean of China (No. AOCQN200812)part of the results of the scientific research project entitled ‘The Legal Issues on the Ecological Damage Caused by Marine Oil Spills
文摘The sources of marine oil spills are mainly from accidents of marine oil tankers or freighters, marine oil-drilling platforms, marine oil pipelines, marine oilfields, terrestrial pollution, oil-bearing atmosphere, and offshore oil production equipment. It is concluded upon analysis that there are two main reasons for marine oil spills: (I) The motive for huge economic benefits of oil industry owners and oil shipping agents far surpasses their sense of ecological risks. (II) Marine ecological safety has not become the main concern of national security. Oil spills are disasters because humans spare no efforts to get economic benefits from oil. The present paper draws another conclusion that marine ecological damage caused by oil spills can be roughly divided into two categories: damage to marine resource value (direct value) and damage to marine ecosystem service value (indirect value). Marine oil spills cause damage to marine biological, fishery, seawater, tourism and mineral resources to various extents, which contributes to the lower quality and value of marine resources.
基金Supported by Special Item of the Public Service Industry Science Research for Environmental Protection,China(201009063)
文摘[Objective] The research aimed to calculate and analyze ecological footprint of the urban agglomeration in Pearl River Delta in 2009. [Method] 9 cities in Pearl River Delta as research zone, by using calculation model of the ecological footprint, ecological footprint and security of the urban agglomeration in Pearl River Delta were calculated. Current situation and sustainable development condition of the ecological environment in Pearl River Delta were conducted quantitative analysis. [Result] Except construction land and woodland, other 4 kinds of lands were all in ecological deficit states in Pearl River Delta. Especially arable land and fossil fuel land had obvious ecological deficit. [Conclusion] Biological resource consumption level and energy consumption level in Pearl River Delta were higher. We ought to take a variety of measures to reduce ecological deficit, making development manner turn toward sustainable direction.
文摘The genetic manipulation of agriculturally important insects now allows the development of genetic sexing and male sterility systems for more highly efficient biologically-based population control programs, most notably the Sterile Insect Technique (SIT), for both plant and animal insect pests. Tetracycline-suppressible (Tet-off) conditional lethal systems may function together so that transgenic strains will be viable and fertile on a tetracycline-containing diet, but female-lethal and male sterile in tetracycline-free condi- tions. This would allow their most efficacious use in a unified system for sterile male-only production for SIT. A critical consideration for the field release of such transgenic insect strains, however, is a determination of the frequency and genetic basis of lethality revertant survival. This will provide knowledge essential to evaluating the genetic stability of the lethality system, its environmental safety, and provide the basis for modifications ensur- ing optimal efficacy. For Tet-off lethal survival determinations, development of large-scale screening protocols should also allow the testing of these modifications, and test the ability of other conditional lethal systems to fully suppress propagation of rare Tet-off survivors. If a dominant temperature sensitive (DTS) pupal lethality system proves efficient for sec- ondary lethality in Drosophila, it may provide the safeguard needed to support the release of sexing/sterility strains, and potentially, the release of unisex lethality strains as a form of genetic male sterility. Should the DTS Prosβ21 mutation prove effective for redundant lethality, its high level of structural and functional conservation should allow host-specific cognates to be created for a wide range of insect species.
基金Tianjin Art and Science Planning Project(D16007)。
文摘The problem of land ecological security directly threatens the sustainable development of many regions,and exploring the spatio-temporal characteristics of land ecological security is helpful for analyzing the land ecological patterns between regions and over time.Based on the interpretation of remote sensing image data for Tianjin in 1980,2000,2010 and 2019,supported by software such as ArcGIS and GeoDa,the changes of land use in the study area are calculated by using the land use dynamic degree.Then,the land ecological security index and spatial autocorrelation analysis methods are used to study the spatial correlations and internal heterogeneity of land ecological security in each district in Tianjin.The results show that:(1)The land use of Tianjin has changed dramatically in the past 40 years:the building land has been expanding,while the farmland and barren have been shrinking continuously.(2)The overall level of land ecological security is in the high security area,and Jizhou District is the highest,while the Central areas and Binhai are low.(3)The spatial heterogeneity of land ecological security is not obvious,but the spatial agglomeration is strong.
基金This work was supported by the National Natural Science Foundation of China(Nos.51778522,51708447)Shaanxi Provincial Program for Innovative Research Team(No.2019TD-025)+1 种基金the National Science Foundation of Shaanxi Province(No.2020JQ-663)the Research Fund of Xi’an University of Architecture and Technology(No.ZR18025).
文摘Currently,the wastewater treatment plants(WWTPs)attempt to achieve the shifting from general pollution parameters control to reduction of organic micropollutants discharge.However,they have not been able to satisfy the increasing ecological safety needs.In this study,the removal of micropollutants was investigated,and the ecological safety was assessed for a local WWTP.Although the total concentration of 31 micropollutants detected was reduced by 83%using the traditional biological treatment processes,the results did not reflect chemicals that had poor removal efficiencies and low concentrations.Of the five categories of micropollutants,herbicides,insecticides,and bactericides were difficult to remove,pharmaceuticals and UV filters were effectively eliminated.The specific photosynthesis inhibition effect and non-specific bioluminescence inhibition effect from wastewater were detected and evaluated using hazardous concentration where 5%of aquatic organisms are affected.The photosynthesis inhibition effect from wastewater in the WWTP was negligible,even the untreated raw wastewater.However,the bioluminescence inhibition effect from wastewater which was defined as the priority biological effect,posed potential ecological risk.To decrease non-specific biological effects,especially of macromolecular dissolved organic matter,overall pollutant reduction strategy is necessary.Meanwhile,the ozonation process was used to further decrease the bioluminescence inhibition effects from the secondary effluent;≥0.34 g O 3/g DOC of ozone dose was recommended for micropollutants elimination control and ecological safety.
基金supported by the National Special Fund for Scientific Research in Public Benefits (Grant No. 20090304608)the National Basic Research Program of China (Grant No. 2007CB109006)+1 种基金the National Natural Science Foundation of China (Grant No. 30500294)the Excellent Talent Program of Hunan Normal University (Grant No. ET31004)
文摘Ecological safety is a major consideration in the commercialization of transgenic fish. Development of sterile transgenic triploid fish through hybridization of transgenic tetraploid fish and transgenic diploid fish is a feasible way to solve this problem. The "all-fish" transgene, pbcAbcGHc, containing the black carp β-actin gene promoter and the open reading frame (ORF) of the black carp growth hormone (GH) gene was constructed and introduced into fertilized eggs of allotetraploid fish through microinjection. Contrast cultivation results showed that the growth rate of 150 day-old P 0 black carp GH gene transgenic allotetraploid fish was much higher than that of controls. Sixty 150 day-old transgenic allotetraploid fish were assayed by PCR for transgene integration and 90% of fish were positive for the transgene. The transgene was detected in 13 of 20 sperm samples from male transgenic allotetraploid fish. RT-PCR detected transcription of the exogenous black carp GH gene in the muscle, liver, kidney and ovaries of the largest transgenic allotetraploid fish. This study has developed P 0 black carp GH gene transgenic allotetraploid fish with a highly increased growth rate, which provides a solid foundation for the establishment of a pure line of transgenic allotetraploid fish and for the large scale production of sterile transgenic triploid fish.
基金supported by the National Natural Science Foundation of China(No.41976145)the Taishan Scholars Climbing Program of Shandong Province of 2019+1 种基金the Science and Technology Major Project of Guangxi(No.AA17202020-4)。
文摘Polyaluminum chloride modified clay(PAC-MC)is a safe and efficient red tide control agent that has been studied and applied worldwide.Although it is well known that the distribution of hydrolytic aluminum species in PAC affects its flocculation,little is known about the influence of particulars aluminum species on the microalgae removal efficiency of PAC-MC;this lack of knowledge creates a bottleneck in the development of more efficient MCs based on aluminum salts.The ferron method was used in this study to quantitatively analyze the distributions of and variations in different hydrolytic aluminum species during the process of microalgae removal by PAC-MC.The results showed that Ala,which made up 5%–20%of the total aluminum,and Alp,which made up 15%–55%of the total aluminum,significantly affected microalgae removal,with Pearson’s correlation coefficients of 0.83 and 0.89,respectively.Most of the aluminum in the PAC-MC sank rapidly into the sediments,but the rate and velocity of settlement were affected by the dose of modified clay.The optimal dose of PAC-MC for precipitating microalgae was determined based on its aluminum profile.These results provide guidance for the precise application of PAC-MC in the control of harmful algal blooms.
基金funded by Central Public-interest Scientific Institution Basal Research Fund (CAFYBB2010001-01)Special Research Program for Public-welfare Forestry (201004008)
文摘In recent years, the quantity and quality of global forest resources are declining continually. Contrarily, the both in China are increasing, which is deeply related to the sustainable forest management and eco-system management in China. With the trend that world community knows more about the important role of forest, more and more functions of forest are recognized. The impact and functions of China's forestry deserve more concern. Based on some experiences in the field of forestry research, the authors introduced and analyzed the key role of China's forestry for the sustainable development, and explained the functions of China's forestry, such as ensuring ecological safety, addressing climate change, improving economic development, promoting social harmony and prospering ecological culture.