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1.
Ying Yong Sheng Tai Xue Bao ; 34(4): 1043-1050, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37078324

RESUMO

We examined the growth decline and health status of farmland protective forest belt (Populus alba var. pyramidalis and Populus simonii shelterbelts) in Ulanbuh Desert Oasis by using airborne hyperspectral and ground-based LiDAR to collect the hyperspectral images and point cloud data of the whole forest belt respectively. Through correlation analysis and stepwise regression analysis, we constructed the evaluation model of the decline degree of farmland protection forest with the spectral differential value, vegetation index, and forest structure parameters as independent variables and the tree canopy dead branch index of the field survey as dependent variables. We further tested the accuracy of the model. The results showed that the evaluation accuracy of the decline degree of P. alba var. pyramidalis and P. simonii by LiDAR method was better than that by hyperspectral method, and that the evaluation accuracy of the combined LiDAR and hyperspectral method was the highest. Using the LiDAR method, hyperspectral method, the combined method, the optimal model of P. alba var. pyramidalis was all light gradient boosting machine model, with the overall classification accuracy being 0.75, 0.68, 0.80, and Kappa coefficient being 0.58, 0.43, 0.66, respectively. The optimal model of P. simonii was random forest model, random forest model, and multilayer perceptron model, with the overall classification accuracy being 0.76, 0.62, 0.81, and Kappa coefficient being 0.60, 0.34, 0.71, respectively. This research method could accurately check and monitor the decline of plantations.


Assuntos
Clima Desértico , Fazendas , Florestas , Populus
2.
Environ Dev Sustain ; : 1-25, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35966337

RESUMO

The coordinated development of industrial agglomeration and economic resilience can drive regional economic advantages; this type of development has become a catalyst for sustainable growth and high-quality development of the economy in China. This study applied models, including the coupling coordination degree, spatial autocorrelation, and Tobit, to explore the heterogeneous characteristics of the coupling of China's industrial agglomeration and regional economic resilience from 2005 to 2019. Additionally, by applying the perspectives of economic and geographic location, indicators were selected to analyze the associated influencing factors, including industrial externalities, new economic geographies, economic policy factors, and other aspects. We found that the overall coupling between industrial agglomeration and economic resilience increased over the study period, but with only a moderate level of coordination. Provinces with high, moderate, and low levels of coordination eventually emerged along a strip-like alternating pattern in space. The dependence increased with an increase in space, but was not significant, and there was a lack of benign interaction between the regions. With respect to interactivity between locations, the interaction of the east and the coast was the most active. There were lower levels of interaction between the west and inland regions. This further confirmed the significant temporal and spatial heterogeneity of the coupling. Environmental pollution, market consumption, the quality of space, and technological support significantly promoted the coupling; opening to the outside world did not. Specifically, with respect to economic location, market consumption and spatial quality had a significant positive effect on the eastern coupling. The center and west regions were significantly affected by economic density and market consumption, and the northeast region was affected by spatial quality and capital intensity. Concerning geographical location, market and technological forces strongly promoted interactions in both the coast and inland regions. The study found that both the government and the market need better guidance to effectively engage with and shape industrial agglomeration and economic resilience in a scientific, reasonable, localized, and distinctive manner.

3.
Chin Geogr Sci ; 32(4): 686-706, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855731

RESUMO

The 14th Five-Year Plan period is a critical period for China to achieve high-quality development. Based on super-efficiency slacks-based measure (SBM) model, grey-related analysis (GRA) and other models, this paper studies the heterogeneity of the coupling relationship among technological innovation, industrial transformation and environmental efficiency in the Huaihai Economic Zone during the period of 2005-2019. In addition, it analyzes the coupling mechanism of single and binary systems to the ternary system, which is of great significance for the collaborative symbiosis among systems. The findings are as follows. 1) The technological innovation, industrial transformation and environmental efficiency (TIE) systems of the Huaihai Economic Zone had significant spatial-temporal heterogeneity. Although their evaluation value fluctuated, the development trends are all positive. Ultimately, technological innovation is characterized by being high in the northeast and low in the southwest around Xuzhou, while other systems are relatively staggered in space. 2) The coupling of TIE systems is in transition, lack of orderly integration and benign interaction. However, the developing trend of interaction is also upward, and a spatial pattern driven by Xuzhou and Linyi as the dual cores has gradually formed. Moreover, the coupling is mostly manifested as outdated technological innovation and industrial transformation. Except for the final coordination of regenerative cities, the other resource types are all in transition. Cities in all traffic locations are still in transition. The overall system interaction of cities on Longhai Line (Lanzhou-Lianyungang Railway) is relatively optimal, and cities on Xinshi Line (Xinxiang-Rizhao Railway) are accelerating toward synergy. 3) The coupling status of TIE systems depends on the development of the single system and the interaction of the binary (2E) system. The coupling is closely related to technological innovation and Technology-Industry system, and is hindered by the inefficient interaction of Technology-Environment system. Specifically, the synergy of regenerative cities is attributed to the advantage of a single system and the effective integration of 2E systems. Beneficial from the advantages of environmental efficiency, the cities on Xinshi Line promote the synergy of the 2E and TIE systems. Therefore, while the Huaihai Economic Zone stimulates the development potential of the single and 2E systems, it is necessary to amplify the superimposition effect of systems in accordance on the basis of resource and location.

4.
J Hazard Mater ; 422: 126844, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34399210

RESUMO

The transmission of airborne antibiotic resistance genes (ARGs) loaded on particle is a significant global public health concern. Up to date, the dispersal pattern of airborne ARGs remains unclear despite their critical role in multiregional transmission. In this study, airborne ARGs loaded on fine particulate matter (PM2.5) and source tracking based on the airflow trajectories were performed by the potential source contribution function (PSCF) and concentration weighted trajectory (CWT) model. The results show that the absolute abundance of ARG subtypes were generally twice times higher in the winter season than that in the summer season, which could be attributable to winter haze events with high particulate matter concentrations in Handan. Exogenous input from serious haze events and local release of ARGs loaded on PM2.5 of air masses may cause higher levels of ARGs in the winter. Moreover, based on the positive correlation between the abundance of ARGs and PM2.5 concentration, a source tracing model of airborne ARGs was proposed to the estimate of ARGs release and dissemination. This study highlights airborne ARGs transmission loaded on PM2.5 of air masses, which facilitating the global spread of antibiotic resistance.


Assuntos
Poluentes Atmosféricos , Antibacterianos , Antibacterianos/farmacologia , China , Resistência Microbiana a Medicamentos/genética , Monitoramento Ambiental , Genes Bacterianos , Material Particulado/análise , Estações do Ano
5.
J Hazard Mater ; 383: 121129, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31546217

RESUMO

Antibiotics ingested in the human gut may create selective pressure to change the composition of the gut microbiota, which could adversely effect the immune system of the host. However, the occurrence and distribution of antibiotics in the human gut remains unclear. A total population of 180 individuals, across three Chinses regions with different economic development levels, including children, adults, and elders, were sampled in 2017. A total of 19 representative antibiotics, including both clinical and veterinary antibiotics, were investigated in human faeces. While clinical use and prescriptions were the main exposure pathways for children, environmental media were the exposure pathway to adults. In addition, significant differences (P < 0.05) in antibiotic residues in human faeces were observed amongst various economic development levels, where human faeces from underdeveloped areas were mostly associated with higher levels of antibiotics. This study first to investigate the occurrence and distribution of typical antibiotics in the faeces of a Chinese population and thereby provide a reference for the intensive study of the effects and mechanisms of antibiotics on human gut microbiota.


Assuntos
Antibacterianos/análise , Fezes/química , Medicina Veterinária , Animais , China , Microbioma Gastrointestinal , Humanos
6.
Plant Biotechnol J ; 17(9): 1804-1813, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30803117

RESUMO

For non-model plants, functional characterization of genes is still hampered by lack of efficient stable transformation procedures. Here, we report a simple, fast and efficient transformation technique with Agrobacterium rhizogenes for generating stable transgenic roots in living plants to facilitate functional studies in vivo. We showed that injection of A. rhizogenes into stems of various plant species lead to stable transgenic root generation, which can sustain plant growth after the original, non-transgenic roots were cut off. A transformation system was established for pigeon pea, a major woody food crop, after optimizing the selection of A. rhizogenes strains, bacterium concentration, injection position and seedling age. RT-PCR and fluorescence observation indicated a transgenic root induction efficiency of about 39% in pigeon pea. Furthermore, induction of hairy roots was achieved in nine out of twelve tested economically important plants at an efficiency of 15-39%. As proof of concept, bimolecular fluorescence complementation (BiFC) assay was applied to test the interaction between CcCIPK14 and CcCBL1/2 in pigeon pea. Additionally, ectopic expression of the bZIP transcription factor MdHY5 from apple confirmed the utility of the transformation technique for engineering anthocyanin synthesis in roots. Taken together, we show that this method allows fast in vivo studies of gene function in a wide range of plant species.


Assuntos
Cajanus/genética , Raízes de Plantas/genética , Transformação Genética , Agrobacterium , Genes de Plantas , Plantas Geneticamente Modificadas
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(1): 181-5, 2016 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-27228764

RESUMO

The secondary geological disasters triggered by the Lushan earthquake on April 20, 2013, such as landslides, collapses, debris flows, etc., had caused great casualties and losses. We monitored the number and spatial distribution of the secondary geological disasters in the earthquake-hit area from airborne remote sensing images, which covered areas about 3 100 km2. The results showed that Lushan County, Baoxing County and Tianquan County were most severely affected; there were 164, 126 and 71 secondary geological disasters in these regions. Moreover, we analyzed the relationship between the distribution of the secondary geological disasters, geological structure and intensity. The results indicate that there were 4 high-hazard zones in the monitored area, one focused within six kilometers from the epicenter, and others are distributed along the two main fault zones of the Longmen Mountain. More than 97% secondary geological disasters occurred in zones with a seismic intensity of VII to IX degrees, a slope between 25 A degrees and 50 A degrees, and an altitude of between 800 and 2 000 m. At last, preliminary suggestions were proposed for the rehabilitation and reconstruction planning of Lushan earthquake. According to the analysis result, airborne and space borne remote sensing can be used accurately and effectively in almost real-time to monitor and assess secondary geological disasters, providing a scientific basis and decision making support for government emergency command and post-disaster reconstruction.

8.
Environ Monit Assess ; 187(6): 355, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25971519

RESUMO

The Three-River Headwaters (TRH) region in the Qinghai-Tibet Plateau, China, is of key importance to the ecological security of China and Southeast Asia and contains some of the most sensitive and fragile ecosystems. Monitoring and evaluating the ecosystem service function and its changes in the TRH region could support decision-making for regional ecological protection and restoration programs. Referencing the concept of ecosystem service and the Millennium Ecosystem Assessment (MA) framework, this study built a system of indicators for monitoring and evaluating the ecosystem service function. Thus, combining a multicriteria decision analysis (MCDA) and weighted linear combination (WLC) with analytic hierarchy process (AHP), we applied the ecosystem service function index (ESFI) based on remote sensing data at 1-km spatial resolution to spatiotemporally monitor the changes during the period 2005-2010. The study results indicated that ESFI had a good performance for monitoring the ecosystem service function and showed an improving trend in the TRH region over the past 5 years. Ecosystem environment recovery not only reflected the changing trend of warm and wet climate but was also a response of the ecological protection project of the Key Ecological Function Zone in the TRH region.


Assuntos
Técnicas de Apoio para a Decisão , Ecossistema , Monitoramento Ambiental/métodos , China , Clima , Conservação dos Recursos Naturais/métodos , Ecologia , Meio Ambiente , Rios , Tibet
9.
J Air Waste Manag Assoc ; 63(2): 170-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23472301

RESUMO

UNLABELLED: This study gathered and processed the available air quality daily reports in 86 cities throughout China in 2001-2011. Urban air quality was assessed in terms of the evolution of the key pollutants, the pollution level, and the PM10 (particulate matter with an aerodynamic diameter < 10 microm) concentrations. The authors conclude that PM10 is the most important pollutant in Chinese cities, especially after the national sulfur dioxide (SO2) controls during the 11th Five Year Plan (FYP; 2006-2010). A notable advance was the reduction of extremely heavily polluted days with air pollution index (API) above 150 from 7% in 2001 to 1% in 2011 in the all-city average. In addition, the average API-derived PM10 concentrations continually decreased during the past 11 yr. Additionally, the pollution pattern of "more severe from south to north "in China became less obvious due to the decline of PM10 concentrations in the northern cities and the more obvious regional characteristics of air pollution. Nevertheless, more pollutants should be included in the API system to fully reflect the air quality status and guide future air pollution controls in Chinese cities. IMPLICATIONS: Air quality daily report, the only publicly accessible observation database in the past decade, provides valuable insight into the air quality in Chinese cities. Using this data set, this paper assesses the status and change of urban air quality in China in 2001-2011, during which great effort was made to mitigate urban air pollution. It is valuable for the further refinement of national air quality control strategies, and the needs of updating the present daily report system are implicated.


Assuntos
Poluentes Atmosféricos , Poluição do Ar/estatística & dados numéricos , Cidades/estatística & dados numéricos , Material Particulado , Algoritmos , China
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(3): 577-82, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21595195

RESUMO

After the occurrence of major natural disasters, it is of great significance that disaster states are assessed timely and accurately for decision-making departments to draw up effective response programs. Multi-spectral remote sensing has a great advantage and potential in disaster assessment, with the characteristics of a wide range of data acquisition, high speed, etc. In several major natural disaster assessments in China, multi-spectral remote sensing technology has played an important role. Firstly, the present paper takes earthquake disasters, floods disasters and drought disasters as examples to summarize the specific applications of major natural disaster assessment based on the multi-spectral remote sensing. Secondly, in these specific applications they suffer from both relative shortage of data sources and limited breadth and depth of application; both of these problems are analyzed. Finally, the future development direction of major natural disaster assessment based on the multi-spectral remote sensing, such as the expansion of multi-spectral remote sensing data acquisition means, the establishment of major natural disasters assessment index system based on remote sensing, and the improvement of the assessment technology system based on multi-spectral remote sensing are also discussed.

11.
J Air Waste Manag Assoc ; 55(9): 1298-305, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16259425

RESUMO

China is undergoing rapid urbanization because of unprecedented economic growth. As a result, many cities suffer from air pollution. Two-thirds of China's cities have not attained the ambient air quality standards applicable to urban residential areas (Grade II). Particulate matter (PM), rather than sulfur dioxide (SO2), is the major pollutant reflecting the shift from coal burning to mixed source pollution. In 2002, 63.2 and 22.4% of the monitored cities have PM and SO2 concentrations exceeding the Grade II standard, respectively. Nitrogen oxides (NOx) concentration kept a relatively stable level near the Grade II standard in the last decade and had an increasing potential in recent years because of the rapid motorization. In general, the air pollutants emission did not increase as quickly as the economic growth and energy consumption, and air quality in Chinese cities has improved to some extent. Beijing, a typical representative of rapidly developing cities, is an example to illustrate the possible options for urban air pollution control. Beijing's case provides hope that the challenges associated with improving air quality can be met during a period of explosive development and motorization.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Óxidos de Nitrogênio/análise , Dióxido de Enxofre/análise , Poluentes Atmosféricos/normas , Poluição do Ar/análise , Carbono , China , Cidades , Carvão Mineral , Cinza de Carvão , Poeira , Economia , Humanos , Óxidos de Nitrogênio/normas , Tamanho da Partícula , Material Particulado , Densidade Demográfica , Centrais Elétricas , Dióxido de Enxofre/normas , Urbanização , Emissões de Veículos
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