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1.
Huan Jing Ke Xue ; 42(1): 501-512, 2021 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-33372504

RESUMO

Considering a background of global warming, the effect of urban heat island (UHI) has become a serious ecological and environmental problem that is commonly faced by modern cities worldwide, posing challenges to the physical and mental health of residents in urban areas, air quality, and the healthy growth of surface vegetation. Using time series MODIS land surface temperature data products from 2001 to 2018, we evaluated the urban heat island intensity (UHII) and its spatiotemporal patterns in 1232 major urban human settlement patches (area>10 km2) across China based on the consistency method. A random forest regression model (RF) was also used to reveal the driving mechanism of urban heat island intensity in China due to human activities, urban morphology, vegetation, topography, and meteorological factors. The results show that more than 90% of cities and towns in China have exhibited significant diurnal heat island phenomena on the scale of human settlements. The diurnal UHII reaches up to (0.75±0.6)℃ and (0.81±0.53)℃, respectively. The daytime UHII in summer was significantly higher than that in winter, while there was little difference in nighttime UHII between summer and winter. During the past 18 years, the daytime UHII in China has shown a slight downward trend, while the nighttime UHII has increased significantly, with no significant change in summer and on mean annual scales. In terms of spatial distribution, the eastern coastal provinces have higher daytime UHII than those of the western or plateau provinces, while the nighttime UHII shows the opposite pattern. The RF regression results show that the average annual rainfall and latitudinal position of cities and towns are the two most important factors controlling the daytime and nighttime UHII in China. Narrowing the differences in vegetation growth between urban and rural environments will have a mitigating effect on the daytime UHII, and controlling the expansion of small and medium-sized towns will also play a positive role in the continuously rising nighttime UHII.


Assuntos
Monitoramento Ambiental , Temperatura Alta , China , Cidades , Humanos , Ilhas
2.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3265-3276, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621212

RESUMO

Ecosystem services (ESs) are the research highlight and hot topic in ecology, geography and environmental economics. Based on the literature database on ecosystem services from Web of Science, Citespace, Carrot 2 and textual analysis were used to review the progresses of ESs research during 1997-2018. The results showed that ESs research institutions and its publications increased quickly in the latest 20 years. The main leading countries on ecosystem services research were the United States, UK, Germany, China and Australia, with the United States being the first in terms of literature volume and the influence. Although the research of ESs in China started relatively late, its development was rapid and the scientific research output increased significantly. Meanwhile, there was a huge gap to the international level, the quality and influence of literature should be improved, and the international cooperation and exchange need to be enhanced too. The hotspots and frontiers of ecosystem services mainly included evaluation methods and models, climate change, biodiversity, land use change, trade-off and synergy, scientific research for decision-making and management. The further research and practice trends include the mechanism of ESs, the indicators and methods for ESs evaluation, the spatiotemporal dynamics of ESs trade-offs and synergies and influencing factors, the coupling relationship between ecosystem services and human well-being, and the scientific research and social needs for sustainable development for decision-making and management.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , China , Ecologia , Humanos
3.
Ying Yong Sheng Tai Xue Bao ; 27(8): 2587-2597, 2016 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-29733147

RESUMO

Urban sprawl has impacted increasingly on water environment quality in watersheds. Based on water environmental response, the simulation and prediction of expanding threshold of urban building land could provide an alternative reference for urban construction planning. Taking three watersheds (i.e., Yundang Lake at complete urbanization phase, Maluan Bay at peri-urbanization phase and Xinglin Bay at early urbanization phase) with 2009-2012 observation data as example, we calculated the upper limit of TN and TP capacity in three watersheds and identified the threshold value of urban building land in watersheds using the regional nutrient management (ReNuMa) model, and also predicted the water environmental effects associated with the changes of urban landscape pattern. Results indicated that the upper limit value of TN was 12900, 42800 and 43120 kg, while that of TP was 340, 420 and 450 kg for Yundang, Maluan and Xinglin watershed, respectively. In reality, the environment capacity of pollutants in Yundang Lake was not yet satura-ted, and annual pollutant loads in Maluan Bay and Xinglin Bay were close to the upper limit. How-ever, an obvious upward trend of annual TN and TP loads was observed in Xinglin Bay. The annual pollutant load was not beyond the annual upper limit in three watersheds under Scenario 1, while performed oppositely under Scenario 3. Under Scenario 2, the annual pollutant load in Yundang Lake was under-saturation, and the TN and TP in Maluan Bay were over their limits. The area thresholds of urban building land were 1320, 5600 and 4750 hm2 in Yundang Lake, Maluan Bay and Xinglin Bay, respectively. This study could benefit the regulation on urban landscape planning.


Assuntos
Monitoramento Ambiental , Urbanização , Qualidade da Água , Baías , China , Planejamento de Cidades , Lagos , Modelos Teóricos , Água , Poluentes Químicos da Água
4.
Ying Yong Sheng Tai Xue Bao ; 26(2): 636-42, 2015 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26094483

RESUMO

The urban cooling island (UCI) effect is put forward in comparison with the urban heat island effect, and emphasizes on landscape planning for optimization of function and way of urban thermal environment. In this paper, we summarized current research of the UCI effects of waters, green space, and urban park from the perspective of patch area, landscape index, threshold value, landscape pattern and correlation analyses. Great controversy was found on which of the two factors patch area and shape index has a more significant impact, the quantification of UCI threshold is particularly lacking, and attention was paid too much on the UCI effect of landscape composition but little on that of landscape configuration. More attention should be paid on shape, width and location for water landscape, and on the type of green space, green area, configuration and management for green space landscape. The altitude of urban park and human activities could also influence UCI effect. In the future, the threshold determination should dominate the research of UCI effect, the reasons of controversy should be further explored, the study of time sequence should be strengthened, the UCI effects from landscape pattern and landscape configuration should be identified, and more attention should be paid to spatial scale and resolution for the precision and accuracy of the UCI results. Also, synthesizing the multidisciplinary research should be taken into consideration.


Assuntos
Cidades , Temperatura , Parques Recreativos , Água
5.
Zhongguo Zhong Yao Za Zhi ; 39(17): 3263-8, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25522608

RESUMO

This paper is aimed to study the effects of nitrogen form on the growth and quality of Chrysanthemums morifolium at the same nitrogen level. In order to provide references for nutrition regulation of Ch. morifolium in field production, pot experiments were carried out in the greenhouse at experimental station of Nanjing Agricultural University. Five proportions of ammonium and nitrate nitrogen were set up and a randomized block design was applied four times repeatedly. The results showed that the growth and quality of Ch. morifolium were significantly influenced by the nitrogen form. The content of chlorophyll and photosynthesis rate were the highest at the NH4(+) -N /NO3(-) -N ratio of 25:75; The activities of NR in different parts of Ch. -morifolium reached the highest at the NH4(+) - N/NO3(-) -N ratio of 0: 100. The contents of nitrate nitrogen in the root and leaves reached the highest at the NH4(+) -N/NO3(-) -N ratio of 50:50. The activities of GS, GOGAT and the content of amylum increased with the ratio of NO3(-) -N decreasing and reached it's maximum at the NH4 + -N/NO3 - -N ratio of 100: 0. The content of ammonium nitrogen were the highest at the NH4 + -N /NO3 --N ratio of 75: 25, while the content of soluble sugar reached the highest at the NH4(+)-N/NO3(-) -N ratio of 25: 75. The content of flavones, chlorogenic acid and 3,5-O-dicoffeoylqunic acid were 57.2 mg x g(-1), 0.673% and 1.838% respectively, reaching the maximum at the NH4(+) -N /NO3(-) -N ratio of 25:75; The content of luteoloside increased with the ratio of NO3(-) -N increasing and reached it's maximum at the NH4(+) -N/NO3(-) -N ratio of 0: 100. The yield of Ch. morifolium reached it's maximum at the NH4(+) -N /NO3(-) -N ratio of 25:75. Nitrogen form has some remarkable influence on the nitrogen metabolism, photosynthesis and growth, Nitrogen form conducive to the growth and quality of Ch. morifolium at the NH4(+) -N /NO3(-) -N ratio of 25: 75.


Assuntos
Clorofila/metabolismo , Chrysanthemum/efeitos dos fármacos , Nitrogênio/farmacologia , Fotossíntese/efeitos dos fármacos , Compostos de Amônio/metabolismo , Compostos de Amônio/farmacologia , Chrysanthemum/crescimento & desenvolvimento , Chrysanthemum/metabolismo , Flores/efeitos dos fármacos , Flores/crescimento & desenvolvimento , Flores/metabolismo , Glutamato Sintase/metabolismo , Glutamato Sintase (NADH)/metabolismo , Glutamato-Amônia Ligase , Nitratos/metabolismo , Nitratos/farmacologia , Nitrogênio/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Caules de Planta/efeitos dos fármacos , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo
6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(3): 753-7, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21595233

RESUMO

The explosive growth of algae in inland water bodies is one of the major water environmental problems in China, and it's very important to monitor the dynamic of algae in both temporal and spatial scales. In the present paper, a model, which was used to extract the algae information from the water body of Taihu Lake using MODIS data, was established based on the remote sensing index and image false color composite methods. Using this model, we studied the algae explosive growth formation process between March and May in 2007. Through the analysis of the temporal and spatial distribution features of the algae outbreak between the spring and summer seasons, an early warning method of algal blooms was proposed, that is, when the MODIS green index mainly concentrated in the range between 0. 6 and 0. 8, the water body of Taihu Lake can be considered to have been in the early alarming stage of algal blooms.


Assuntos
Monitoramento Ambiental/métodos , Eutrofização , Lagos , Telemetria , China
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(4): 1075-9, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20545165

RESUMO

Chlorophyll is a very important indictor for the eutrophication status of lake water body. Using remotely sensed data to achieve real-time dynamic monitoring of the spatial distribution of chlorophyll has great importance. This paper aims to find the best band for the hyperspectral ratio model of chlorophyll-a, and take advantage of this model to implement remote sensing retrieval of algae in Taihu Lake. By the analysis of the spectral reflectance and water quality sampling data of the surface water body, the regression model between the ratio of reflectance and chlorophyll-a was built, and it was showed that the ratio model between the wavelengths around 700 and 625 nm had a relatively high coefficient value of determination (R2), while the ratio model constructed with 710 nm and visible wavelengths showed a descended R2 following with the increment of the visible wavelengths. Combined with in-situ water samplings analysis and spectral reflectance measurement, the results showed that it's possible to retrieve algae water body using the MODIS green index (GI). The spatial distributions of chlorophyll-a and algae in Taihu Lake were extracted successfully using MODIS data with the algorithm developed in this paper.


Assuntos
Monitoramento Ambiental , Eutrofização , Lagos , Tecnologia de Sensoriamento Remoto , Algoritmos , Clorofila , Clorofila A , Água Doce , Modelos Teóricos , Qualidade da Água
8.
Huan Jing Ke Xue ; 30(4): 1244-8, 2009 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-19545037

RESUMO

Based on the concept of ecosystem services and welfare, a definition of a sustainable city is proposed, and a quantitative model to describe sustainable welfare is established. With the analysis of the major issues and driving forces of sustainable city construction in China, the approaches for sustainable city construction are proposed as follows: to promote study on the theory and methodology of sustainable city construction, to set up and perfect institutional and management systems, and to establish a performance assessment system and an effective operation mechanism for sustainable city construction in China.


Assuntos
Planejamento de Cidades , Conservação dos Recursos Naturais/métodos , Ecossistema , Planejamento Ambiental , Monitoramento Ambiental/métodos , China
9.
Int J Pharm ; 333(1-2): 95-102, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17110064

RESUMO

The drug percolation thresholds of 5-fluorouracil-loaded ethylene-vinyl acetate stent coatings were estimated to characterize their drug release behavior and mechanical properties. The stent coatings were prepared using 5-fluorouracil (5-FU) as antitumor drug and ethylene-vinyl acetate (EVA) as matrix forming material in different ratios. In vitro release assays were carried out exposing only one side of coating to pH 6.5 PBS. Based on the release profiles, the drug percolation thresholds were estimated as 0.21 of total porosity (corresponding to ca. 32%, w/w of the drug), which is in approximately agreement with the atomic force microscopy (AFM) result. Based on the coating tensible break strength and tear break strength data, the mechanical percolation thresholds of drug were obtained as 39.7+/-0.3 and 37.5+/-1.4% (w/w) of drug content, respectively.


Assuntos
Antimetabólitos Antineoplásicos/química , Materiais Revestidos Biocompatíveis , Portadores de Fármacos , Fluoruracila/química , Polivinil/química , Stents , Química Farmacêutica , Difusão , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia de Força Atômica , Modelos Químicos , Modelos Estatísticos , Porosidade , Solubilidade , Estresse Mecânico , Resistência à Tração , Fatores de Tempo
10.
Huan Jing Ke Xue ; 28(11): 2425-31, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-18290459

RESUMO

L-THIA Model was used to simulate the amounts of NPS pollutants in 2 catchments of Sanjiao watershed (Sj1, Sj2) in Hanyang district, and the total simulated amount of NPS loads in Sj1 and Sj2 were 1.82 x 10(4) kg, 1.38 x 10(5) kg, respectively. Based on the theory of resource-sink" and interaction of pattern with process, a series of BMPs, including green roof, grassland, porous pavement, infiltration trench, vegetative filter strip and wet pond, were optimized, and effects of BMPs were simulated along the surface runoff pathway. The results show that total pollutants outputs entering Sj1 and Sj2 account for 14.65% and 6.57%, respectively. Combining L-THIA model and BMPs in series is a proper measure for non-point source pollution control and urban development planning at watershed or region scale.


Assuntos
Plantas/metabolismo , Poluentes Químicos da Água/análise , Poluição Química da Água/prevenção & controle , Purificação da Água/métodos , Biodegradação Ambiental , Cidades , Simulação por Computador , Modelos Teóricos , Nitrogênio/análise , Nitrogênio/metabolismo , Fósforo/análise , Fósforo/metabolismo , Chuva , Movimentos da Água , Poluentes Químicos da Água/metabolismo
11.
Huan Jing Ke Xue ; 27(1): 31-6, 2006 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-16599116

RESUMO

It is most important for managing urban non-point source (NPS) pollution, actualizing the urban sustainable development as well, that zoning planning of urban NPS pollution control is studied. A case study on principles and methods of zoning planning in urban NPS pollution is carried out. Principles of urban sustainable development, priority of urban NPS pollution sensitivity, similarity of urban NPS control direction and region conjugate are put forward. Besides, it is for the first time that a more quantitive method is presented, in the case of Hanyang district, Wuhan city, which is based on L-THIA model and spatial analysis technique in GIS. Assessment of NPS pollution status quo, as well as analysis of NPS sensitivity, is the kernel component of the quantitive method. Hanyang might be divided into four NPS pollution control zones. It is helpful for decision-making of regional NPS pollution control.


Assuntos
Poluentes da Água/análise , Poluição da Água/prevenção & controle , Abastecimento de Água/análise , China , Cidades , Modelos Teóricos , Movimentos da Água
12.
Huan Jing Ke Xue ; 27(11): 2170-5, 2006 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-17326421

RESUMO

The change of land use and management practices is one of the most important factors that affecting water quality, proper land use management practices can improve water quality in a watershed. A stepwise regression model was used for finding the relationship between lake water quality and urban land use types, and rural residential, urban residential, commercial land and bottomland were determined as the main sources of non-point source pollution (NPS). The 17 catchments in the study area were clustered into 3 groups through land use types, representing rural residential, urban residential, commercial land and bottomland separately. According to the different characters of landscape structures in each group, appropriate countermeasures designed for effective NPS control simplified the practices and improved the maneuverability of urban NPS control.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Urbanização , Poluição da Água/prevenção & controle , China , Planejamento de Cidades , Análise de Regressão
13.
Huan Jing Ke Xue ; 25(6): 32-9, 2004 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15759877

RESUMO

Non-point source (NPS) pollution is the prominent source of water pollution in many countries, included America and China, of the world. Urban NPS pollution was attached little importance for long, compared with agriculture NPS pollution. While urbanization is the dominant form of land-use change in terms of impacts on water quality, the hydrology, other physical properties of watersheds as well as their NPS pollution potential at present. The formation of urban NPS pollution of water could be described by "source-process-sink". Urbanization has changed the source, process and sink of urban NPS pollution. A review was conducted on the international researches of urbanization impacts on NPS pollution in urban water environment from the point of view of "describe-predict and evaluation-application". The studies of urbanization impacts on urban NPS pollution were focused on modeling the process of urban NPS pollution by hydrologic model, predicting the pollutants load of NPS pollution. It is a fresh methodology that the relationship between urbanization and urban NPS pollution of water was analyzed by the method of landscape change and ecological process. The research on temporal-spatial comprehensive impacts of landscape pattern changes, led by urbanization, on the urban NPS pollution will be one of the hotspots.


Assuntos
Urbanização , Poluição da Água/análise , Abastecimento de Água/análise , Água Doce/análise
14.
Zhongguo Zhong Yao Za Zhi ; 28(1): 41-3, 2003 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15015265

RESUMO

OBJECTIVE: To find out the bioactive principles of Alpinia tonkinensis, by investigating its chemical constituents. METHOD: It was extracted with MeOH, distributed by different solvents, and isolated via column chromatography on silica gel. RESULT: Six compounds were elucidated through spectral analysis, which were as follows: 4',7-dimethylkaempferol(I), 5-hydroxy-3',4',7-trimethoxyflavanone(II), kumatakenin(III), 4',5,7-trimethoxyflavonol(IV), ombuine(V), and kaempferol(VI). CONCLUSION: Six flavonoids were isolated from this plant for the first time, and so were four compounds from genus Alpinia.


Assuntos
Alpinia/química , Flavonoides/isolamento & purificação , Plantas Medicinais/química , Flavonoides/química , Quempferóis/química , Quempferóis/isolamento & purificação , Rizoma/química
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