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Heterogeneous population distribution enhances resistance to wheat lodging by optimizing the light environment
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作者 Yibo Hu Feng Qin +6 位作者 Zhen Wu Xiaoqin Wang Xiaolong Ren Zhikuan Jia Zhenlin Wang Xiaoguang Chen Tie Cai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2211-2226,共16页
Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechan... Lodging is still the key factor that limits continuous increases in wheat yields today,because the mechanical strength of culms is reduced due to low-light stress in populations under high-yield cultivation.The mechanical properties of the culm are mainly determined by lignin,which is affected by the light environment.However,little is known about whether the light environment can be sufficiently improved by changing the population distribution to inhibit culm lodging.Therefore,in this study,we used the wheat cultivar“Xinong 979”to establish a low-density homogeneous distribution treatment(LD),high-density homogeneous distribution treatment(HD),and high-density heterogeneous distribution treatment(HD-h)to study the regulatory effects and mechanism responsible for differences in the lodging resistance of wheat culms under different population distributions.Compared with LD,HD significantly reduced the light transmittance in the middle and basal layers of the canopy,the net photosynthetic rate in the middle and lower leaves of plants,the accumulation of lignin in the culm,and the breaking resistance of the culm,and thus the lodging index values increased significantly,with lodging rates of 67.5%in 2020–2021 and 59.3%in 2021–2022.Under HD-h,the light transmittance and other indicators in the middle and basal canopy layers were significantly higher than those under HD,and the lodging index decreased to the point that no lodging occurred.Compared with LD,the activities of phenylalanine ammonia-Lyase(PAL),4-coumarate:coenzyme A ligase(4CL),catechol-O-methyltransferase(COMT),and cinnamyl-alcohol dehydrogenase(CAD)in the lignin synthesis pathway were significantly reduced in the culms under HD during the critical period for culm formation,and the relative expression levels of TaPAL,Ta4CL,TaCOMT,and TaCAD were significantly downregulated.However,the activities of lignin synthesis-related enzymes and their gene expression levels were significantly increased under HD-h compared with HD.A partial least squares path modeling analysis found significant positive effects between the canopy light environment,the photosynthetic capacity of the middle and lower leaves of plants,lignin synthesis and accumulation,and lodging resistance in the culms.Thus,under conventional high-density planting,the risk of wheat lodging was significantly higher.Accordingly,the canopy light environment can be optimized by changing the heterogeneity of the population distribution to improve the photosynthetic capacity of the middle and lower leaves of plants,promote lignin accumulation in the culm,and enhance lodging resistance in wheat.These findings provide a basis for understanding the mechanism responsible for the lower mechanical strength of the culm under high-yield wheat cultivation,and a theoretical basis and for developing technical measures to enhance lodging resistance. 展开更多
关键词 canopy light environment LIGNIN LODGING population distribution WHEAT
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Designing an Elderly-Friendly City in Cardiff: Cultivating Sense of Security for the Aging Population: Transforming Butetown for the Entertainment, Health, and Diversification of the Elderly
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作者 Yedi Tian 《Journal of World Architecture》 2024年第3期30-35,共6页
As an important part of urban construction,elderly-friendly construction is crucial to the formation of an elderly-friendly society,which has been widely recognized internationally.Especially after the COVID-19 pandem... As an important part of urban construction,elderly-friendly construction is crucial to the formation of an elderly-friendly society,which has been widely recognized internationally.Especially after the COVID-19 pandemic,various organizations around the world have called for changes in public space and urban building planning,with an emphasis on the accessibility of green spaces.This underscores the complexity and difficulty of integrating vulnerable groups of the elderly into cities and using infrastructure and public space. 展开更多
关键词 Aging population Elderly-friendly city Urban planning Built environment Design
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Report on the compilation of the Population,Environment and Sustainable Development Atlas of China (PESDAC) 被引量:3
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作者 LIAO Zhi-jte LIU Yue (Institute of Geography, the Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第2期199-201,203-204,共5页
关键词 maps PESDAC Report on the compilation of the population environment and Sustainable development Atlas of China
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EVOLUTION OF POPULATION, RESOURCES, ENVIRONMENT AND INTEGRATED STRATEGY OF THEIR DEVELOPMENT IN SHANGHAI 被引量:1
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《Chinese Geographical Science》 SCIE CSCD 2000年第3期11-17,共2页
关键词 PRED RESOURCES environment and INTEGRATED STRATEGY OF THEIR development IN SHANGHAI EVOLUTION OF population
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Population,development,and environment in India
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作者 C.M.Lakshmana 《Chinese Journal of Population,Resources and Environment》 2013年第4期367-374,共8页
High population growth and continued economic development have caused serious environmental damage in the Asia Pacific region.However,the recent experience is that the pace of environmental degradation is faster in de... High population growth and continued economic development have caused serious environmental damage in the Asia Pacific region.However,the recent experience is that the pace of environmental degradation is faster in developing countries than in developed countries.To this end,the study seeks to assess the impact of population pressure on India's environment,with particular reference to the degradation of natural endowments like land and water resources and the resultant environmental pollution in the six regions of India.The rapid economic growth and expansion of infrastructure development in recent decades have not come without serious environmental consequences particularly in the southern,northern,and western regions.But in the eastern,north-eastern,and central regions of the country,environmental damage has been mainly due to rapid population growth. 展开更多
关键词 INDIA population POVERTY URBANIZATION development environment
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Population,Resources,the Environment and Sustainable Development
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作者 Zhu Jiefang 《Meteorological and Environmental Research》 CAS 2019年第1期16-18,25,共4页
The formation of population,resources and environmental issues is directly related to the excessive growth of population,the excessive use and consumption of resources,and environmental pollution. Therefore,it is nece... The formation of population,resources and environmental issues is directly related to the excessive growth of population,the excessive use and consumption of resources,and environmental pollution. Therefore,it is necessary to curb the excessive growth of population,rationally utilize natural resources,enhance the purification capacity of the environment,and promote the coordinated development of population,resources and the environment to make the economic development process sustainable. 展开更多
关键词 population RESOURCES environment SUSTAINABLE development
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Coordinated Development of Population, Economy and Environment System and Diagnosis of Its Obstacle Factors in Nanjing
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作者 Liu Binglin Jiang Shengnan +3 位作者 Xu Minghui Xing Yun Wu Haotian Li Lu 《Meteorological and Environmental Research》 CAS 2019年第5期38-42,共5页
Promoting the coordinated development of regional population,economy and environment is beneficial to the realization of sustainable development.Based on the construction of evaluation index system of coordinated deve... Promoting the coordinated development of regional population,economy and environment is beneficial to the realization of sustainable development.Based on the construction of evaluation index system of coordinated development of systems,the entropy weight-TOPSIS method and coupling coordination model,the coordinated development degree of population,economy and environment system in Nanjing was measured,and the temporal variation characteristics of each subsystem and their coordinated development degree form 1997 to 2016 were analyzed.The results showed that the development of population,economy system and environment system in Nanjing was generally in a continuous upward trend.Among them,the economy system developed fastest.The coordinated development degree of population,economy system and environment system in Nanjing was constantly increasing but still at a low level;the degree was only in the primary coordination phase,and its type was environment lagging.The economy subsystem and environment subsystem were important factors restricting the development of population,economy and environment in Nanjing,and the main obstacle factor was the production of industrial solid waste.The results above can provide a scientific basis for promoting the coordinated development of population,economy and environment system in Nanjing and achieving regional sustainable development. 展开更多
关键词 population economy and environment system COORDINATED development degree of systems Entropy weight-TOPSIS OBSTACLE factors NANJING
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Population Environment and Sustainable Development in Guangdong
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《China Population Today》 1998年第4期9-9,共1页
Tomaintainrapideconomicdevelopmentrequiresanoptimumpopulationsize.Otherwise,theoverrapidincreaseofpopulatio... Tomaintainrapideconomicdevelopmentrequiresanoptimumpopulationsize.Otherwise,theoverrapidincreaseofpopulationmayspeedupoverc... 展开更多
关键词 and environment GUANGDONG population development
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Effects of Different Application Times of Tillering Fertilizer on Grain Yield and Population Development of Double-cropping Rice Transplanted by Machine
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作者 商庆银 吕伟生 +5 位作者 曾勇军 黄山 杨秀霞 谭雪明 石庆华 潘晓华 《Agricultural Science & Technology》 CAS 2015年第9期1860-1864,1868,共6页
The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering... The application of tillering fertilizer plays an important role in promoting rice tillering and improving rice yield. However, under the condition of mechanical transplanting, the optimal application time of tillering fertilizer is still unclear. In this study, the early rice cultivar Zhongjiazao 17 and late rice cultivar H You 518 were used as materials, and the effects of different application times of tillering fertilizer on yield and population development of double-cropping rice transplanted by machine were investigated. The tillering fertilizer was applied 7(D07), 10(D10) and 13(D13) d after the transplanting, respectively. The results showed that compared with those in the D07 treatment groups, the yield of early rice in the D10 and D13 treatment groups were reduced by 9.4% and 3.8%, respectively, and the yield of late rice in the D10 and D13 treatment groups were reduced by 4.5% and 12.6%,respectively. However, there were no significant differences in rice yield among the treatment groups. The application time of tillering fertilizer showed significant effects on grain number per panicle and seed setting rate of early rice. The grain number per panicle in the D10 treatment group was significantly lower than that in the D07 treatment group, and the seed setting rate of the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). For the late rice, the effect of application time of tillering fertilizer on effective tiller number was most obvious, and the effective tiller number in the D13 treatment group was significantly lower than that in the D07 treatment group(P〈0.05). Compared with those in the D07 treatment group, the effective tiller numbers, leaf area indexes and biomasses in the D10 and D13 treatment groups were all trended to be decreased. Therefore,to improve the quality of population and fulfill the high-yielding potential of double-cropping rice transplanted by machine, the tillering fertilizer should be applied as early as possible after rice seedlings turn green. 展开更多
关键词 Double-cropping rice Mechanical transplanting Tillering fertilizer Application time YIELD population development
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13^(th) World Population Day Themes Poverty, Population and Development
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《China Population Today》 2002年第4期19-19,共1页
关键词 World population Day Themes Poverty population and development TH
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Spatial Coupling Relationship and Driving Mechanism of Population and Economy in Rural Areas in Qinling-Daba Mountains,China 被引量:3
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作者 XIAO Jie QIAO Jiajun +2 位作者 HAN Dong LIU Yang PAN Tao 《Chinese Geographical Science》 SCIE CSCD 2023年第5期779-795,共17页
Addressing the issue of the healthy and coordinated development of the population and economic factors in rural areas will not only help consolidate and expand the achievements of poverty alleviation,but will also lay... Addressing the issue of the healthy and coordinated development of the population and economic factors in rural areas will not only help consolidate and expand the achievements of poverty alleviation,but will also lay a foundation for comprehensive rural revitalization.In this paper,the spatial coupling relationship between the population and economic factors in rural areas in the QinlingDaba Mountains,China,is explored to provide a reference for rural revitalization and regional sustainable development in poverty areas.Sixty-eight county units in rural areas in the Qinling-Daba Mountains,as well as the population and economic factors in rural areas,are used to study the spatial coupling relationship between population and economy,as well as the driving mechanism,in rural areas in the Qinling-Daba Mountains from 2010 to 2020.The results show that a population contraction phenomenon occurred in the rural areas in the Qinling-Daba Mountains,and the spatial agglomeration trends of the population and economic factors were consistent.The agglomeration was mainly located in the suburban areas of the municipal area,and the agglomeration degree was significantly higher in these areas than in other areas.In terms of the spatial distribution,the economic development level of the rural areas in the northeastern part of the Qinling-Daba Mountains was generally higher than that in the central and western parts,and the unbalanced trends of the population and economic spatial differentiation in the eastern and western regions were significant.The spatial coupling relationship between the population and economy changed from coordinated development to economic advancement.This was mainly due to the mutual restriction and joint actions of the industrial structure,capital situation,natural environment,policies,and institutional regulations,among which the industrial structure and capital status had significant effects. 展开更多
关键词 rural poverty population distribution economic development pattern spatial coupling influencing factors rural revitalization Qinling-Daba Mountains China
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Mapping QTLs with epistatic effects and QTL×environment interactions for plant height using a doubled haploid population in cultivated wheat 被引量:37
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作者 Kunpu Zhang Jichun Tian Liang Zhao Shanshan Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第2期119-127,共9页
Quantitative trait loci (QTLs) for plant height in wheat (Triticum aestivum L.) were studied using a set of 168 doubled haploid (DH) lines, which were derived from the cross Huapei 3/Yumai 57. A genetic linkage ... Quantitative trait loci (QTLs) for plant height in wheat (Triticum aestivum L.) were studied using a set of 168 doubled haploid (DH) lines, which were derived from the cross Huapei 3/Yumai 57. A genetic linkage map was constructed using 283 SSR and 22 EST-SSR markers. The DH population and the parents were evaluated for wheat plant height in 2005 and 2006 in Tai'an and 2006 in Suzhou. QTL analyses were performed using the software of QTLNetwork version 2.0 based on the mixed linear model. Four additive QTLs and five pairs of epistatic effects were detected, which were distributed on chromosomes 3A, 4B, 4D, 5A, 6A, 7B, and 7D. Among them, three additive QTLs and three pairs of epistatic QTLs showed QTL×environment interactions (QEs). Two major QTLs, Qph4B and Qph4D, which accounted for 14.51% and 20.22% of the phenotypic variation, were located similar to the reported locations of the dwarfing genes Rhtl and Rht2, respectively. The Qph3A-2 with additive effect was not reported in previous linkage mapping studies. The total QTL effects detected for the plant height explained 85.04% of the phenotypic variation, with additive effects 46.07%, epistatic effects 19.89%, and QEs 19.09%. The results showed that both additive effects and epistatic effects were important genetic bases of wheat plant height, which were subjected to environmental modifications, and caused dramatic changes in phenotypic effects. The information obtained in this study will be useful for manipulating the QTLs for wheat plant height by molecular marker-assisted selection (MAS). 展开更多
关键词 doubled haploid population epistatic effects plant height quantitative trait loci QTL×environment interactions wheat (Triticum aestivum L.)
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Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses 被引量:12
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作者 LiuXiaolin ChangYaqing +3 位作者 XiangJianhai LiFuhua LiuXianjie BrovkinaElenaPavlovna 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第2期255-264,共10页
Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultura... Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months). 展开更多
关键词 Chlamys farreri population HYBRIDIZATION medium-term growth and development HETEROSIS
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Statement by Minister Peng Peiyun at the International Conference on Population and Development 被引量:5
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《China Population Today》 1994年第5期2-4,共3页
The stabilization of the world population and the achievement of sustained development depend not only on the endeavours of governments of nations,but also on further strengthening and promotion of international coope... The stabilization of the world population and the achievement of sustained development depend not only on the endeavours of governments of nations,but also on further strengthening and promotion of international cooperation,The developed countries should make eforts to improve the international economic environment,increase funds for population and development programmes and transfer technology at preferable conditions. 展开更多
关键词 STATEMENT MINISTER population CONFERENCE Peiyun Peng development INTERNATIONAL and by
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Risk factors for acute kidney injury following coronary artery bypass graft surgery in a Chinese population and development of a prediction model 被引量:3
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作者 Yang LI Xue-Jian HOU +5 位作者 Tao-Shuai LIU Shi-Jun XU Zhu-Hui HUANG Peng-Yun YAN Xiao-Yu XU Ran DONG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2021年第9期711-719,共9页
BACKGROUND Acute kidney injury(AKI)after coronary artery bypass graft(CABG)surgery is associated with significant morbidity and mortality.This retrospective study aimed to establish a risk score for postoperative AKI ... BACKGROUND Acute kidney injury(AKI)after coronary artery bypass graft(CABG)surgery is associated with significant morbidity and mortality.This retrospective study aimed to establish a risk score for postoperative AKI in a Chinese population.METHODS A total of 1138 patients undergoing CABG were collected from September 2018 to May 2020 and divided into a derivation and validation cohort.AKI was defined according to the Kidney Disease Improving Global Outcomes(KDIGO)criteria.Multivariable logistic regression analysis was used to determine the independent predictors of AKI,and the predictive ability of the model was determined using a receiver operating characteristic(ROC)curve.RESULTS The incidence of cardiac surgery–associated acute kidney injury(CSA-AKI)was 24.17%,and 0.53%of AKI patients required dialysis(AKI-D).Among the derivation cohort,multivariable logistic regression showed that age≥70 years,body mass index(BMI)≥25 kg/m2,estimated glomerular filtration rate(eGFR)≤60 mL/min per 1.73 m2,ejection fraction(EF)≤45%,use of statins,red blood cell transfusion,use of adrenaline,intra-aortic balloon pump(IABP)implantation,postoperative low cardiac output syndrome(LCOS)and reoperation for bleeding were independent predictors.The predictive model was scored from 0 to32 points with three risk categories.The AKI frequencies were as follows:0-8 points(15.9%),9-17 points(36.5%)and≥18 points(90.4%).The area under of the ROC curve was 0.730(95%CI:0.691-0.768)in the derivation cohort.The predictive index had good discrimination in the validation cohort,with an area under the curve of 0.735(95%CI:0.655-0.815).The model was well calibrated according to the Hosmer-Lemeshow test(P=0.372).CONCLUSION The performance of the prediction model was valid and accurate in predicting KDIGO-AKI after CABG surgery in Chinese patients,and could improve the early prognosis and clinical interventions. 展开更多
关键词 AKI RED Risk factors for acute kidney injury following coronary artery bypass graft surgery in a Chinese population and development of a prediction model
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CHINESE JOURNAL OF Population Resources and Environment Annual Contents 被引量:1
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《Chinese Journal of Population,Resources and Environment》 2011年第4期95-96,共2页
关键词 PAGE CHINESE JOURNAL OF population Resources and environment Annual Contents
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Multi Location Field Evaluation of BC1F2 Sorghum Populations for Striga Resistance in Niger
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作者 Ousseini Ardaly Abdou Aissata Mamadou Ibrahim +2 位作者 Yaw Eleblu John Saviour Ofori Kwadwo Ousmane Zakari Moussa 《American Journal of Plant Sciences》 CAS 2024年第10期1010-1021,共12页
In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected... In Niger, a landlocked country, sorghum is the second staple food cultivated over the country by smallholder farmer. The crop is important for human and animal consumption. Despite its importance, the crop is affected by biotic and abiotic constraints. Among those constraints, striga has a high impact on yield. In fact, to survive, farmers are growing their local preferred sorghum varieties wish is highly sensible to the weed. Striga management is a challenge that requires a permanent solution. In addition, the development of high-yielding Striga resistant genotypes will be appreciated by farmers. The development of striga resistance will be based on the breeding population performances under farmer’s diverse environmental conditions adaptation. The main objective of this study is to evaluate two breeding populations for striga resistance in two different environments at Boulke and Dibissou in Tahoua region, to identify the early and high-yielding striga tolerant genotypes under natural infestation. 展开更多
关键词 Striga Resistance SORGHUM Breeding population Multi environment
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Population growth, management and environmental degradation in China
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作者 Richard Louis Edmonds 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1989年第1期1-14,共14页
Environmental problems in China can be divided into two large classes: pollution and destruction of natural environment. Environmental degradation is particularly serious in areas with rapid population growth. In this... Environmental problems in China can be divided into two large classes: pollution and destruction of natural environment. Environmental degradation is particularly serious in areas with rapid population growth. In this paper, some of China's major environmental problems, particularly those concerned with land, forests, and continental waters are introduced in order to see how population growth and management have affected these resources over the past few decades. It is also explained how the Chinese plan to cope and eventually solve these problems. 展开更多
关键词 population environment degradation.
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Population dynamics of excited atoms in non-Markovian environments at zero and finite temperature
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作者 邹红梅 方卯发 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第8期177-182,共6页
The population dynamics of a two-atom system, which is in two independent Lorentzian reservoirs or in two independent Ohmic reservoirs respectively, where the reservoirs are at zero temperature or finite temperature, ... The population dynamics of a two-atom system, which is in two independent Lorentzian reservoirs or in two independent Ohmic reservoirs respectively, where the reservoirs are at zero temperature or finite temperature, is studied by using the time-convolutionless master-equation method. The influences of the characteristics and temperature of a non-Markovian environment on the population of the excited atoms are analyzed. We find that the population trapping of the excited atoms is related to the characteristics and the temperature of the non-Markovian environment. The results show that, at zero temperature, the two atoms can be effectively trapped in the excited state both in the Lorentzian reservoirs and in the Ohmic reservoirs. At finite temperature, the population of the excited atoms will quickly decay to a nonzero value. 展开更多
关键词 population excited atom non-Markovian environment temperature
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ECO-ETHOLOGY OF POPULATION REGULATION AMONG GERBILS IN THE SAHARAN ENVIRONMENT Study of the dynamics of populations,of their demographic impetus their food strategies and their reproduction strategies among four species of gerbil in Morocco.(Meriones sha
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作者 Zaime-A 《干旱区资源与环境》 CSCD 1993年第Z1期398-399,共2页
The following study of populations of gerbil in arid and Saharan terrain enables us toexamine the relationships between the essential determinants in the cycles of abundance. Social unity, methods of spatial distribut... The following study of populations of gerbil in arid and Saharan terrain enables us toexamine the relationships between the essential determinants in the cycles of abundance. Social unity, methods of spatial distribution, dispersal, strategies for food and repro-duction, and also disappearance, are linked to climatic factors and defined according to therecognised hierarchy of stages of perceptions in Ecology individual, group, population, 展开更多
关键词 GERBIL Arid and Saharan environments population DYNAMICS Utilisation of Resources
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