Journal articles: 'Vegetation indece'

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Veltrop, Marcel H. A. M., Maurice J. L. M. F. Bancsi, Rogier M. Bertina, and Jan Thompson. "Role of Monocytes in Experimental Staphylococcus aureus Endocarditis." Infection and Immunity 68, no. 8 (August 1, 2000): 4818–21. http://dx.doi.org/10.1128/iai.68.8.4818-4821.2000.

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ABSTRACT In the pathogenesis of bacterial endocarditis (BE), the clotting system plays a cardinal role in the formation and maintenance of the endocardial vegetations. The extrinsic pathway is involved in the activation of the coagulation pathway with tissue factor (TF) as the key protein. Staphylococcus aureus is a frequently isolated bacterium from patients with BE. We therefore investigated whetherS. aureus can induce TF activity (TFA) on fibrin-adherent monocytes, used as an in vitro model of BE. We also assessed in vivo in rabbits with catheter induced vegetations, the effect of S. aureus infection on vegetational TFA. In vitro experiments showed that adherent S. aureus induced TFA on fibrin-adherent monocytes which was optimal at a bacterium/monocyte ratio of 1 to 1. Monocyte damage occurred when this ratio exceeded 4 to 1 (visually) or 6 to 1 (propidium iodide influx) Consequently, TFA decreased. In vivoS. aureus led to very high bacterial numbers in the vegetations and a significant increase of their weight. However, TFA of infected vegetations was the same as of sterile ones. This may be due to the high bacteria to monocyte ratio as well as bacterium-induced monocyte damage. Teicoplanin treatment of infected rabbits reduced bacterial numbers in the blood and in the vegetations. Two-day treatment resulted in an increase of vegetational TFA, but after four-day treatment vegetational TFA dropped, most probably due to a suboptimal bacterium/monocyte ratio. S. aureus endocarditis in etoposide (Vepesid)-treated rabbits, leading to a selective monocytopenia, caused a rapid death of the animals. In these rabbits no vegetations were found at all. We conclude that, likeStreptococcus sanguis and Staphylococcus epidermidis, S. aureus is able to induce TFA in fibrin-adherent blood monocytes. In addition, monocytes have a protective effect during the course of S. aureusendocarditis.

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Xu Mingzhu, 许明珠, 徐浩 Xu Hao, 孔鹏 Kong Peng, and 吴艳兰 Wu Yanlan. "结合植被指数和卷积神经网络的遥感植被分类方法." Laser & Optoelectronics Progress 59, no. 24 (2022): 2428005. http://dx.doi.org/10.3788/lop202259.2428005.

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Dhakal, Richa, and Ram Asheshwar Mandal. "APPLICATION OF VEGETATION INDEXES TO ASSESS CARBON STOCK." Mercator 21, no. 1 (June 15, 2022): 1–14. http://dx.doi.org/10.4215/rm2022.e21018.

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This was objectively conducted to estimate the carbon stock, to show the relation between carbon stock and indices and to assess the factors affecting carbon stock in community forests. Three community forests (CFs) namely Gumalchowki, Mahakalsthan and Mahalaxmi of Chandragiri Municipality in Nepal were selected as research sites. Altogether 135 plots were randomly established to collect data from the field. The biomass was calculated using Chave et al., equation which was converted into carbon stock multiplying by default value 0.47. The values of Normalized Difference Vegetation Index (NDVI), Difference Vegetation Index (DVI) and Infrared Percentage Vegetation Index (IPVI) were calculated and regression equation between the indices and carbon stock was performed. The result showed that total above ground carbon stock was highest in Mahalaxmi CF with 30.42 ton/ha, followed by Mahakalsthan CF with 22.62 ton/ha and comparatively lowest with 21.55 ton/ha in Gumalchowki CF. The regression analysis between carbon stock and indices showed significantly and positive correlation. The R2 value of NDVI of Gumalchowki, Mahakalsthan and Mahalaxmi CF were found to be 0.51, 0.54 and 0.58, also, RMSE value of CFs were 1.41, 1.36 and 1.91 respectively. Principal component analysis showed that road construction, transmission line expansion, soil erosion, encroachment, disease, weeds, recreation, illegal logging are the major factors affecting carbon stock in all three community forests. Keywords: Carbon, Nepal, Community Forests.

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Liang, Juan, Chen Liu, Gui-Quan Sun, Li Li, Lai Zhang, Meiting Hou, Hao Wang, and Zhen Wang. "Nonlocal interactions between vegetation induce spatial patterning." Applied Mathematics and Computation 428 (September 2022): 127061. http://dx.doi.org/10.1016/j.amc.2022.127061.

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Yoon, Jung-Beom, Young-Nam Yoon, and Yoon-Ha Kim. "Utilization of Vegetation Indice in Agricultural Field." Journal of Agriculture & Life Science 55, no. 5 (October 30, 2021): 1–9. http://dx.doi.org/10.14397/jals.2021.55.5.1.

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Augustin, Pascal, Ghada Alsalih, Yoann Launey, Sandrine Delbosc, Liliane Louedec, Véronique Ollivier, Françoise Chau, et al. "Predominant Role of Host Proteases in Myocardial Damage Associated with Infectious Endocarditis Induced by Enterococcus faecalis in a Rat Model." Infection and Immunity 81, no. 5 (March 11, 2013): 1721–29. http://dx.doi.org/10.1128/iai.00775-12.

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ABSTRACTInfective endocarditis (IE) remains a life-threatening infectious disease with high morbidity and mortality. The objectives of the present study are to assess the host proteolytic activities of the vegetations and their cytotoxic potential in a rat model of experimental IE. Rats were infected with a strain ofEnterococcus faecalisof particularly low virulence and weak protease expression. We tested the presence of proteases released by infiltrated leukocytes (matrix metalloproteinases and elastase) or producedin situwithin the septic vegetation, such as those linked to the fibrinolytic system (plasmin and plasminogen activators). We also assessed the tissue damage induced by the infective thrombusin vitroandex vivo. The model of IE was characterized by larger and more extensive vegetations in infected than in nonseptic rats and by an intense neutrophil infiltrate interfacing with the injured underlying tissue. Neutrophil extracellular DNA was shown to trap bacteria and to produce increased levels of cell-free DNA in plasma. Matrix metalloproteinase-9, elastase, and plasminogen activators were increased in septic versus nonseptic vegetations (as shown by zymography and immunohistology). Finally, proteolysis of the extracellular matrix and apoptosis were shown to be associated with host proteases. Bacteria exhibited no detectable proteolytic activity or direct cytotoxic effects. Bacterial membranes/dead bacteria were sufficient to induce leukocyte recruitment and activation that could promote vegetation formation and growth. Our results suggest that, despite the lack of bacterial proteases, the continuous attractant signals coming from bacterial colonies may lead to a chronic and deleterious aggression toward myocardial/valvular tissues by host proteases.

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Reyes-González, Arturo, David G. Reta-Sánchez, Juan I. Sánchez-Duarte, Víctor M. Rodríguez-Moreno, Enrique Hernández-Leal, and Iván Franco-Gaytán. "Desarrollo del coeficiente de cultivo para cártamo forrajero basado en índices de vegetación." Tecnología y ciencias del agua 11, no. 6 (November 1, 2020): 39–80. http://dx.doi.org/10.24850/j-tyca-2020-06-02.

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El coeficiente de cultivo (Kc) es esencial para la programación del riego en la agricultura. Los objetivos de este estudio fueron monitorear la altura e índice de vegetación NDVI (índice de vegetación de diferencia normalizada, NDVI por sus siglas en inglés) del cártamo durante dos ciclos de cultivo, desarrollar un nuevo Kc con base en el NDVI y calcular la evapotranspiración de cultivo (ETc), tomando en cuenta los valores de Kc. El estudio se realizó en los ciclos otoño-invierno 2016-2017 y 2017-2018 en Matamoros, Coahuila, México. Se evaluaron los cultivares Guayalejo, Selkino y CD-868. La siembra se realizó en un suelo seco el 10 y 12 de diciembre de 2016 y 2017, respectivamente. En el ciclo 2016-2017 se aplicaron tres riegos de auxilio y en el ciclo 2017-2018 dos. El NDVIcampo se obtuvo con el equipo GreenSeeker y el NDVIsatelital de imágenes Landsat 7 y 8. Se estableció una relación entre el NDVIcampo y el Kc tomado del manual 56 de la FAO. Los resultados indicaron curvas similares de NDVIcampo en ambos ciclos. Altos coeficientes de determinación (r2 = 0.93 y 0.89) se obtuvieron entre el NDVIcampo y el Kc de FAO-56. Se generó una ecuación lineal (Kc = 1.064 * NDVI + 0.212) para ambos ciclos. Los nuevos valores de Kc se multiplicaron por la evapotranspiración de referencia (ETo) para calcular ETc. Con esta ecuación se propone un modelo de cálculo para derivar recomendaciones de lámina de riego acordes con la etapa fenológica del cártamo.

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Swami, Abhishek. "Impact of Automobile Induced Air Pollution on roadside vegetation: A Review." ESSENCE International Journal for Environmental Rehabilitation and Conservation 9, no. 1 (August 15, 2018): 101–16. http://dx.doi.org/10.31786/09756272.18.9.1.113.

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Aleixo, Natacha Cíntia Regina, and João Cândido André Silva Neto. "Índice de vegetação e comportamento da temperatura do ar em Tefé/Amazonas/Brasil." Revista Brasileira de Geografia Física 11, no. 2 (2018): 864–76. http://dx.doi.org/10.26848/rbgf.v10.6.p864-876.

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Aleixo, Natacha Cíntia Regina, and João Cândido André Silva Neto. "Índice de vegetação e comportamento da temperatura do ar em Tefé/Amazonas/Brasil." Revista Brasileira de Geografia Física 11, no. 3 (2018): 864–76. http://dx.doi.org/10.26848/rbgf.v11.3.p864-876.

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Spitkó, T., Z. Nagy, Zsubori ZT, C. Szőke, T. Berzy, J. Pintér, and Marton CL. "Connection between normalized difference vegetation index and yield in maize." Plant, Soil and Environment 62, No. 7 (July 24, 2016): 293–98. http://dx.doi.org/10.17221/676/2015-pse.

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Caiati, Carlo, Paolo Pollice, Mario Erminio Lepera, and Stefano Favale. "Pacemaker Lead Endocarditis Investigated with Intracardiac Echocardiography: Factors Modulating the Size of Vegetations and Larger Vegetation Embolic Risk during Lead Extraction." Antibiotics 8, no. 4 (November 19, 2019): 228. http://dx.doi.org/10.3390/antibiotics8040228.

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Lead pacemaker infection is a complication on the rise. An infected oscillating mass attached to the leads (ILV) is a common finding in this setting. Percutaneous extraction of the leads and of the device is the best curative option. However, extraction of leads with large masses can be complicated by pulmonary embolism. The aim of this study was to understand the factors associated with large ILV using a sophisticated ultrasound technique to visualize the masses, namely intracardiac echocardiography (ICE), and investigate whether larger masses induce more complications during and after extraction. Percutaneous lead extraction and peri-procedural ICE were done in 36 patients (pts) (75 ± 11 years old, 74% males). Vegetations (max dimension = 8.2 ± 4.1 mm) in the right cavity were found in 26 of them, mostly adhering to the leads. We subdivided the patients into 2 groups: with vegetation size < 1 cm (18 pts) and vegetation size ≥ 1 cm (8 pts). By univariate analysis, we found that patients in group 1 were more often taking anticoagulation therapy (p = 0.03, Phi (Phi coefficient) = −0.5, OR [odds ratio] 0.071) and had signs of local pocket infection (p = 0.02, Phi = −0.52, OR 0.059) while significantly more patients in group 2 had diabetes (p = 0.08, Phi = 0.566, OR 15); moreover the patients in group 2 showed a trend toward a more frequent positive blood culture (p = 0.08, Phi = 0.39, OR 5.8) and infection with coagulase negative staphylococci (p = 0.06, Phi = 0.46, OR 8.3). At multivariate analysis, only 3 factors (diabetes, younger age and anticoagulation therapy) were independently associated with ILV size: diabetes, associated with larger vegetations (group 2), showed the largest beta value (0.44, p = 0.008); age was inversely correlated with ILV size (beta value = −32, p = 0.038), and anticoagulation therapy (beta value = −029, p = 0.048) was more commonly associated with smaller vegetations (group 1). Larger ILV were not associated with more complications or death during or after the extraction. Conclusion: diabetes, anticoagulation therapy and age are independent predictors of lead vegetation size. The embolic potential of large ILV during extraction was modest, so ILVs >1cm are not a contraindication to percutaneous extraction of infected leads.

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Pavlova, Anna I. "APPLICATION OF VEGETATION INDECES FOR DOGITAL SOIL MAPPING BASED ON SENTINEL-2 SPACE IMAGES." Siberian Journal of Life Sciences and Agriculture 13, no. 6 (December 30, 2021): 119–31. http://dx.doi.org/10.12731/2658-6649-2021-13-6-119-131.

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At present, the works devoted to the creation of digital soil maps using geographic information systems (GIS) and remote sensing (RS) data are relevant. In the work the analysis of vegetation indices (VI) for soil mapping was carried out, the maps of vegetation indices were created: Normalized Difference Vegetation Index (NDVI), Optimized Soil-Adjusted Vegetation Index (OSAVI), Soil-Adjusted Vegetation Index (SAVI), Tranformed Soil-Adjusted Vegetation Index (TSAVI), Enhanced Vegetation Index2 (EVI2) for the territory of ZAO Mirny farm of Kochenevsky District using Sentinel-2 A satellite image (May 10, 2021). ). As a result it was revealed that the vegetation indices OSAVI and EVI2 allow to establish spatial boundaries between the main types of soils of automorphic, half-hydromorphic and hydromorphic moisture regimes. Background. Multispectral space and aerial photos for thematic mapping of soil resources are of greater practical application. Sentinel-2 A space image with good spatial and spectrozonal resolution (10 m, 20 m and 60 m) and territorial coverage (290 km) was used in this article. This made it possible to calculate and analyze various vegetation indices for the purposes of digital soil mapping. Purpose. аnalysis of vegetation indices for digital soil mapping based on Sentinel-2 A images. Materials and research methods. The research was carried out on the territory of CJSC Mirniy, Kochenevsky District, Novosibirsk Region. The methods of digital processing of space images, mapping and geoinformation analysis with the use of Sentinel-2 A satellite image (May 10, 2021) were used. The method of equal intervals was used for comparative analysis of images. This allowed using GIS ArcGIS to make thematic maps of images with the allocation of gradations: very low, low, average, above average, high value. Results. Field soil surveys were carried out on the territory of CJSC Mirny farm in Kochenevsky district of Novosibirsk Region. Using SAGA geoinformation system the space image was atmospherically corrected and spatially referenced, NDVI, OSAVI, TSAVI, EVI2 raster maps were compiled. Geoinformation analysis of the large-scale 1:1000 soil map and raster EVI maps revealed that OSAVI allows to establish spatial boundaries between the main types of soils of automorphic, half-hydromorphic and hydromorphic moisture regimes. Very low values of VI are typical for the soils of hydromorphic humidification regime, formed near small lakes, along the banks of the Sharikh river. Very low values of UI have objects of hydrography, marsh peaty, meadow-marsh humus soils, marshy and peated marshes, marsh solonchaks, marsh solonchaks, formed in lowered areas of relief with depth of groundwater occurrence less than 0.5 m. Ploughed ordinary chernozems, deposited in the upper and middle part of the gentle slope, have low values of WP. These are soils of automorphous moisture regime with depth of groundwater occurrence more than 6 m. Average and above average values are characteristic of gray forest saltwort soils under woody vegetation, as well as meadow-chernozem soils under meadow vegetation in the lower part of the gentle slope with groundwater occurrence depth from 3 to 4 m. High WI values were obtained for meadow soils with dense grass cover. Wetting conditions of soils, location in the relief, and vegetation type significantly influence VI values. The obtained VV values can be used at the stage of training data preparation in the form of reference classes for basic soil types required for automatic image recognition.

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Costa, Thomaz Corrêa e. Castro da, Luciano José de Oliveira Accioly, Maria Ap José de Oliveira, Nivaldo Burgos, and Flávio Hugo Barreto Batista da Silva. "Phytomass mapping of the "seridó caatinga" vegetation by the plant area and the normalized difference vegetation indeces." Scientia Agricola 59, no. 4 (December 2002): 707–15. http://dx.doi.org/10.1590/s0103-90162002000400014.

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Phytomass is a critical information for economic and environmental activities like the establishment of policies for timber resources, forest management, studies of plant nutrient cycling, CO2 sink, among other. The phytomass of a Caatinga area was obtained by an empirical method using normalized difference vegetation index (NDVI) of Landsat images, the plant area index (PAI) and the phytomass inventory. At a first stage, linear, logarithmic and non-linear models were developed and tested. Bush and tree specimens were considered in the study, so that most of the individuals that contribute to the spectral answer detected by satellite images were included. At a second stage, the orbital parameter NDVI was used to map the PAI, which was used to map the phytomass, based on the relationship of this phytomass as a function of PAI. The residues between measurements and estimates based on NDVI varied from 0 to 84%, while the residues of total dry weight of phytomass per ha obtained by mapping and by dendrometrical equations varied from 5 to 104%, with a large trend of 166 and 448% in open Caatinga areas, due to the contribution of the herbaceous stratum to NDVI.

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Veloso, Tiago Rafael, Aziz Chaouch, Thierry Roger, Marlyse Giddey, Jacques Vouillamoz, Paul Majcherczyk, Yok-Ai Que, Valentin Rousson, Philippe Moreillon, and José Manuel Entenza. "Use of a Human-Like Low-Grade Bacteremia Model of Experimental Endocarditis To Study the Role of Staphylococcus aureus Adhesins and Platelet Aggregation in Early Endocarditis." Infection and Immunity 81, no. 3 (December 17, 2012): 697–703. http://dx.doi.org/10.1128/iai.01030-12.

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ABSTRACTAnimal models of infective endocarditis (IE) induced by high-grade bacteremia revealed the pathogenic roles ofStaphylococcus aureussurface adhesins and platelet aggregation in the infection process. In humans, however,S. aureusIE possibly occurs through repeated bouts of low-grade bacteremia from a colonized site or intravenous device. Here we used a rat model of IE induced by continuous low-grade bacteremia to explore further the contributions ofS. aureusvirulence factors to the initiation of IE. Rats with aortic vegetations were inoculated by continuous intravenous infusion (0.0017 ml/min over 10 h) with 106CFU ofLactococcus lactispIL253 or a recombinantL. lactisstrain expressing an individualS. aureussurface protein (ClfA, FnbpA, BCD, or SdrE) conferring a particular adhesive or platelet aggregation property. Vegetation infection was assessed 24 h later. Plasma was collected at 0, 2, and 6 h postinoculation to quantify the expression of tumor necrosis factor (TNF), interleukin 1α (IL-1α), IL-1β, IL-6, and IL-10. The percentage of vegetation infection relative to that with strain pIL253 (11%) increased when binding to fibrinogen was conferred onL. lactis(ClfA strain) (52%;P= 0.007) and increased further with adhesion to fibronectin (FnbpA strain) (75%;P< 0.001). Expression of fibronectin binding alone was not sufficient to induce IE (BCD strain) (10% of infection). Platelet aggregation increased the risk of vegetation infection (SdrE strain) (30%). Conferring adhesion to fibrinogen and fibronectin favored IL-1β and IL-6 production. Our results, with a model of IE induced by low-grade bacteremia, resembling human disease, extend the essential role of fibrinogen binding in the initiation ofS. aureusIE. Triggering of platelet aggregation or an inflammatory response may contribute to or promote the development of IE.

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HONJO, Tsuyoshi, and Tadashi TAKAKURA. "Estimation of Vegetation Cover Ratio in Urban Area by Using Vegetation Index." Journal of the Japanese Institute of Landscape Architects 52, no. 5 (1988): 283–87. http://dx.doi.org/10.5632/jila1934.52.5_283.

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Niculescu, Simona, Cédric Lardeux, and Jenica Hanganu. "Synergy between Sentinel-1 radar time series and Sentinel-2 optical for the mapping of restored areas in Danube delta." Proceedings of the ICA 1 (May 16, 2018): 1–10. http://dx.doi.org/10.5194/ica-proc-1-82-2018.

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Wetlands are important and valuable ecosystems, yet, since 1900, more than 50&thinsp;% of wetlands have been lost worldwide. An example of altered and partially restored coastal wetlands is the Danube Delta in Romania. Over time, human intervention has manifested itself in more than a quarter of the entire Danube surface. This intervention was brutal and has rendered ecosystem restoration very difficult. Studies for the rehabilitation&thinsp;/&thinsp;re-vegetation were started immediately after the Danube Delta was declared as a Biosphere Reservation in 1990. Remote sensing offers accurate methods for detecting and mapping change in restored wetlands. Vegetation change detection is a powerful indicator of restoration success. The restoration projects use vegetative cover as an important indicator of restoration success. To follow the evolution of the vegetation cover of the restored areas, satellite images radar and optical of last generation have been used, such as Sentinel-1 and Sentinel-2. Indeed the sensor sensitivity to the landscape depends on the wavelength what- ever radar or optical data and their polarization for radar data. Combining this kind of data is particularly relevant for the classification of wetland vegetation, which are associated with the density and size of the vegetation. In addition, the high temporal acquisition frequency of Sentinel-1 which are not sensitive to cloud cover al- low to use temporal signature of the different land cover. Thus we analyse the polarimetric and temporal signature of Sentinel-1 data in order to better understand the signature of the different study classes. In a second phase, we performed classifications based on the Random Forest supervised classification algorithm involving the entire Sentinel-1 time series, then starting from a Sentinel-2 collection and finally involving combinations of Sentinel-1 and -2 data.

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Takano, Tsubasa, Yohsuke Kominami, and Hiromi Mizunaga. "Do Coarser Gap Mosaics in Conifer Plantations Induce More Seed Dispersal by Birds? Temporal Changes during 12 Years after Gap Creation." Forests 10, no. 10 (October 18, 2019): 918. http://dx.doi.org/10.3390/f10100918.

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The creation of canopy gaps is thought to be an efficient silvicultural operation to diversify species composition of monoculture conifer plantations; however, the shortage of regeneration materials in overclosed plantations is one of the concerns related to this operation. Seed dispersal by frugivorous birds may play an important role in inducing the spread of native broad-leaved trees in canopy gaps in plantations in the warm temperate zone of central Japan because bird-dispersed woody species are abundant in this area. We monitored the dynamics of the abundance and species composition of bird-dispersed seeds over 12 years after gap creation in the canopy of a Japanese cypress (Chamaecyparis obtusa (Siebold et Zucc.) Endl.) plantation. We also studied the effects of gap-mosaic patterns (from many small gaps to fewer large gaps) on dispersal. We used a hierarchical Bayesian zero-inflated Poisson model to analyze the factors affecting seed dispersal by frugivorous birds. Seed dispersal by birds increased with gap age except for just after gap creation. Dispersal in coarser gap mosaics was more abundant than that in finer gap mosaics. The species diversity of dispersed seeds in each seed trap (α-diversity) and plot (γ-diversity) showed similar trends in terms of temporal changes and differences between plots related to seed dispersal abundance; β-diversity did not. These trends might have been caused by shrub-vegetation development after gap creation. The effects of shrub vegetation were classified into the attraction by fruits borne within the vegetation, as well as other effects related to vegetation, such as functions of perch availability and insect presence as a food source. The presence of bird-dispersed seeds was strongly promoted by vegetation in all seasons, but only marginally by the presence of fruit-bearing vegetation. However, fruits attracted seed dispersal by frugivorous birds in the winter season. Our results suggest that both vegetation development and fruiting are important for promoting seed dispersal by frugivorous birds, and those effects are different in different seasons according to vegetation conditions and shifting food resources.

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Williams, Dean R., Philip J. Smethurst, and Brad M. Potts. "Phosphorus fertiliser can induce earlier vegetative phase change in Eucalyptus nitens." Australian Journal of Botany 52, no. 2 (2004): 281. http://dx.doi.org/10.1071/bt03135.

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Many eucalypts are heteroblastic, exhibiting a distinct change in leaf morphology through their ontogeny. The physiological and chronological age at which the tree switches from the production of juvenile foliage to adult foliage (vegetative phase change) can be under strong genetic control and influenced to some extent by environment. We studied the effect of nitrogen (N) and phosphorus (P) fertiliser on the growth and vegetative phase change in Eucalyptus nitens. Whilst neither fertiliser treatment affected tree height at 3.5 years of age, P fertiliser significantly reduced the length of the juvenile vegetative phase. In contrast, N, but not P, has been shown to promote flowering. These findings support the argument that vegetative and reproductive maturity are genetically and physiologically uncoupled in Eucalyptus.

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Jaksibaev, Rashid. "DETERMINATION OF VEGETATION INDEX, LAND SURFACE TEMPERATURE AND PRECIPITATION AMOUNTS USING REMOTE SENSING DATA." JOURNAL OF AGRO PROCESSING 5, no. 2 (May 30, 2020): 4–10. http://dx.doi.org/10.26739/2181-9904-2020-5-1.

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Dankert, Jacob, Janneke van der Werff, Willem Joldersma, and Sebastian A. J. Zaat. "Interleukin 1α Increases the Susceptibility of Rabbits to Experimental Viridans Streptococcal Endocarditis." Infection and Immunity 74, no. 2 (February 2006): 947–52. http://dx.doi.org/10.1128/iai.74.2.947-952.2006.

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ABSTRACT Major predisposing conditions for infective endocarditis (IE) are the presence of a cardiac platelet-fibrin vegetation and of circulating bacteria with relatively low susceptibility to microbicidal activity of blood platelets. The influence of proinflammatory conditions on development of IE is unknown. We studied the effects of the presence of a catheter, inserted to induce platelet-fibrin vegetations, and of the proinflammatory cytokine interleukin-1α in rabbit experimental IE. Leaving the catheter in place after challenge with viridans streptococci predisposed for experimental IE. IE susceptibility rapidly decreased between 0 to 6 h after catheter removal. The catheter did not predispose for IE by providing a site for bacterial adherence, as almost all explanted catheters were culture negative. To mimic the proinflammatory influence of the catheter, rabbits were injected with interleukin-1α at 24 h after catheter removal and at 0, 1, and 3 h before bacterial challenge. Interleukin-1α injected 3 h prior to challenge significantly increased IE incidence due to a platelet releasate-susceptible Streptococcus oralis strain, with rapidly increasing numbers of bacteria within the vegetations. IE due to the Streptococcus sanguis strain less susceptible to platelet releasate was not enhanced. We conclude that proinflammatory stimuli, either a catheter or interleukin-1α, enhanced susceptibility to IE due to the platelet releasate-susceptible S. oralis. As with rabbits, temporary intravascular proinflammatory conditions may predispose for IE in humans at risk for this serious infection.

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Vitkovskaya, I., M. Batyrbayeva, and L. Spivak. "THE ESTIMATE OF THE SPATIAL-TEMPORAL FEATURES OF VEGETATION COVER OF KAZAKHSTAN BASED ON TIME SERIES SATELLITE INDECES IN 2000-2015." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (June 24, 2016): 1067–71. http://dx.doi.org/10.5194/isprs-archives-xli-b8-1067-2016.

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The article presents the evaluation of spatial-temporal characteristics of Kazakhstan arid and semi-arid areas' vegetation on the basis of time series of differential and integral vegetation indices. It is observed the negative trend of integral indices for the period of 2000-2015. This fact characterizes the increase of stress influence of weather conditions on vegetation in Kazakhstan territory during last decade. Simultaneously there is a positive trend of areas of zones with low values of IVCI index. Zoning of the territory of Kazakhstan was carried out according to the long-term values of the normalized integral vegetation index, which is characteristic of the accumulated amount of green season biomass. Negative trend is marked for areas of high productivity zones, long-term changes in the areas of low productivity zones have tend to increase. However long-term values of the area of the middle zone are insignificantly changed. Location boundaries of this zone in the latitudinal direction connects with a weather conditions of the year: all wet years, the average area is located between 46°- 49°N, and the all dry years - between 47°30'- 54°N. The map of frequency of droughts was formed by low values of the integral vegetation condition index which calculated from satellite data.

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Vitkovskaya, I., M. Batyrbayeva, and L. Spivak. "THE ESTIMATE OF THE SPATIAL-TEMPORAL FEATURES OF VEGETATION COVER OF KAZAKHSTAN BASED ON TIME SERIES SATELLITE INDECES IN 2000-2015." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (June 24, 2016): 1067–71. http://dx.doi.org/10.5194/isprsarchives-xli-b8-1067-2016.

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The article presents the evaluation of spatial-temporal characteristics of Kazakhstan arid and semi-arid areas' vegetation on the basis of time series of differential and integral vegetation indices. It is observed the negative trend of integral indices for the period of 2000-2015. This fact characterizes the increase of stress influence of weather conditions on vegetation in Kazakhstan territory during last decade. Simultaneously there is a positive trend of areas of zones with low values of IVCI index. Zoning of the territory of Kazakhstan was carried out according to the long-term values of the normalized integral vegetation index, which is characteristic of the accumulated amount of green season biomass. Negative trend is marked for areas of high productivity zones, long-term changes in the areas of low productivity zones have tend to increase. However long-term values of the area of the middle zone are insignificantly changed. Location boundaries of this zone in the latitudinal direction connects with a weather conditions of the year: all wet years, the average area is located between 46°- 49°N, and the all dry years - between 47°30'- 54°N. The map of frequency of droughts was formed by low values of the integral vegetation condition index which calculated from satellite data.

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Leonard, Daniel, Anton S. Sinery, and Jacob Manusawai. "Strategi Pengelolaan Taman Wisata Alam Gunung Meja melalui Penataan Kawasan." Cassowary 3, no. 2 (November 15, 2020): 153–91. http://dx.doi.org/10.30862/casssowary.cs.v3.i2.44.

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The purpose of this research is to formulate management strategies related to the condition and potential of the park. The results showed that land cover of Gunung Meja natural tourism park dominated by natural forest (77.5%), followed by plantations forest (11.7%), the former garden area (5.6%), gardens (3.4%) and open land, electricity network, tower and street with percent smaller extent. Potential natural forest vegetation is very high, includes 159 species of trees (186 individuals/ha, high diversity indeck), 149 species of poles (867 individuals / ha, medium diversity indeck), 164 species of saplings (3,904 individuals / ha, medium diversity indeck) and 177 species of seedlings (32,300 individuals / ha, medium diversity indeck) with the total of species is 223, as well as forest vegetation plants, medicinal plants and farm / plantation vegetation. The diversity of wildlife species include 15 species of mammals (2 species protected), 35 species of birds (12 species protected), 21 other species (8 lizards, 3 amphibia, 9 snakes and 1 turtles) and 14 species of insects (1 species protected). Potential support includes Japanese monument, caves, water and social communities. Utilization of the region has not done so well that affect the area as a result of the existence of agricultural activities, logging and utilities. Referral management includes policies (policies that embody accommodate all interests through the zoning system by protected zone, farm exploit zone and buffer zone).

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Vitkovskaya, I. S. "SATELLITE DATA PROCESSING ALGORITHM IN THE PROCESS OF FORMATION OF THE TIME SERIES OF VEGETATION INDEXES." Eurasian Physical Technical Journal 18, no. 2 (June 11, 2021): 90–95. http://dx.doi.org/10.31489/2021no2/90-95.

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The diverse spectral indexes computed from the satellite images are used extensively in the world practice of remote sensing of the Earth from space. This approach proved its validity for the satellite monitoring of the underlying terrain, detection of ongoing changes and trends of their dynamic patters. Accumulated prodigious amount of satellite data, the state-of-the-art methods of thematic interpretation gave rise to creation of services providing free access to both images and to image processing results. Notwithstanding the foregoing, in the furtherance of the local and regional scale it turns out that usage of the end products of thematic processing of space information supplied by the known available services was not efficient on all occasions. Consequently, we may need to generate our own archives of the long-term series of satellite indexes. The volume of files containing the digital index matrices computed based on the MODIS satellite low resolution data subject to the complete coverage of the territory of Kazakhstan surpasses 4 Gb. This often results in the delayed computations, and on frequent occasions in infeasibility of computation of a full matrix when the medium specs computers are employed. This article is focused on the satellite data processing algorithm in the process of formation of the time series of vegetation indexes. As a consequence, the multi-year archive of vegetation indexes (over a period of 2001-2020), which provided a basis for trend analysis of the underlying terrain, determination of their future trends and forecasting of their changes was created within the territory of the Republic.

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Ivanov, M. A., S. S. Mukharamova, O. P. Yermolaev, and B. Essuman-Quainoo. "Mapping Croplands with a Long History of Crop Cultivation Using Time Series of Modis Vegetation Indices." Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki 162, no. 2 (2020): 302–13. http://dx.doi.org/10.26907/2542-064x.2020.2.302-313.

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Santiago, Jose-Luis, and Esther Rivas. "Advances on the Influence of Vegetation and Forest on Urban Air Quality and Thermal Comfort." Forests 12, no. 8 (August 23, 2021): 1133. http://dx.doi.org/10.3390/f12081133.

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Kloet, S. P. Vander, and N. M. Hill. "The paradox of berry production in temperate species of Vaccinium." Canadian Journal of Botany 72, no. 1 (January 1, 1994): 52–58. http://dx.doi.org/10.1139/b94-007.

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Vegetative cover, fruiting phenology, and seed production was estimated from six Vaccinia heathlands on the Avalon Peninsula of Newfoundland so that the efficacy of the Vaccinium seed bank could be ascertained. Out of the six species of Vaccinium present in this vegetation, only V. angustifolium and V. boreale were recovered from 120 soil cores taken; V. uliginosum and V. vitis-idaea, two of the most common species on these heaths, were not represented in the seed bank at all, yet experimentally buried seeds from both these taxa will successfully germinate when exhumed after 6 years of burial. Indeed, 81% of the germinants were from taxa with dry fruits such as Kalmia, Luzula, Juncus, and Agrostis. Paucity of Vaccinium seed in the soil column may be due in part to fungal rot and avian predation. Key words: Vaccinium, seed production, seed banks, heaths.

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Cvetković, M., N. Micic, G. Djuric, and B. Bosancic. "Leader management techniques to induce vegetative bud development in plum." Acta Horticulturae, no. 1175 (October 2017): 41–48. http://dx.doi.org/10.17660/actahortic.2017.1175.9.

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Zhao, Xia-Xia, and Jian-Zhong Wang. "Rich Spatiotemporal Dynamics of a Vegetation Model with Noise and Periodic Forcing." Discrete Dynamics in Nature and Society 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/218053.

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The growth of vegetation is undeniably subject to random fluctuations arising from environmental variability and internal effects due to periodic forcing. To address these issues, we investigated a spatial version of a vegetation model including seasonal rainfall, noise, and diffusion. By numerical simulations, we found that noise can induce the pattern transition from stationary pattern to other patterns. More specifically, when noise intensity is small, patch invasion is induced. As noise intensity further increases, chaotic patterns emerge. For the system with noise and seasonal rainfall, it exhibits frequency-locking phenomena. Patterns transition may be a warning signal for the onset of desertification and thus the obtained results may provide some measures to protect vegetation, such as reducing random factors or changing irrigation on vegetation.

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van Hateren, Theresa C., Marco Chini, Patrick Matgen, and Adriaan J. Teuling. "Ambiguous Agricultural Drought: Characterising Soil Moisture and Vegetation Droughts in Europe from Earth Observation." Remote Sensing 13, no. 10 (May 19, 2021): 1990. http://dx.doi.org/10.3390/rs13101990.

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Long-lasting precipitation deficits or heat waves can induce agricultural droughts, which are generally defined as soil moisture deficits that are severe enough to negatively impact vegetation. However, during short soil moisture drought events, the vegetation is not always negatively affected and sometimes even thrives. Due to this duality in agricultural drought impacts, the term “agricultural drought” is ambiguous. Using the ESA’s remotely sensed CCI surface soil moisture estimates and MODIS NDVI vegetation greenness data, we show that, in major European droughts over the past two decades, asynchronies and discrepancies occurred between the surface soil moisture and vegetation droughts. A clear delay is visible between the onset of soil moisture drought and vegetation drought, with correlations generally peaking at the end of the growing season. At lower latitudes, correlations peaked earlier in the season, likely due to an earlier onset of water limited conditions. In certain cases, the vegetation showed a positive anomaly, even during soil moisture drought events. As a result, using the term agricultural drought instead of soil moisture or vegetation drought, could lead to the misclassification of drought events and false drought alarms. We argue that soil moisture and vegetation drought should be considered separately.

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Gimenez, Rollin, Guillaume Lassalle, Arnaud Elger, Dominique Dubucq, Anthony Credoz, and Sophie Fabre. "Mapping Plant Species in a Former Industrial Site Using Airborne Hyperspectral and Time Series of Sentinel-2 Data Sets." Remote Sensing 14, no. 15 (July 29, 2022): 3633. http://dx.doi.org/10.3390/rs14153633.

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Industrial activities induce various impacts on ecosystems that influence species richness and distribution. An effective way to assess the resulting impacts on biodiversity lies in vegetation mapping. Species classification achieved through supervised machine learning algorithms at the pixel level has shown promising results using hyperspectral images and multispectral, multitemporal images. This study aims to determine whether airborne hyperspectral images with a high spatial resolution or phenological information obtained by spaceborne multispectral time series (Sentinel-2) are suitable to discriminate species and assess biodiversity in a complex impacted context. The industrial heritage of the study site has indeed induced high spatial heterogeneity in terms of stressors and species over a reduced scale. First, vegetation indices, derivative spectra, continuum removed spectra, and components provided by three feature extraction techniques, namely, Principal Component Analysis, Minimal Noise Fraction, and Independent Component Analysis, were calculated from reflectance spectra. These features were then analyzed through Sequential Floating Feature Selection. Supervised classification was finally performed using various machine learning algorithms (Random Forest, Support Vector Machines, and Regularized Logistic Regression) considering a probability-based rejection approach. Biodiversity metrics were derived from resulted maps and analyzed considering the impacts. Average Overall Accuracy (AOA) reached up to 94% using the hyperspectral image and Regularized Logistic Regression algorithm, whereas the time series of multispectral images never exceeded 72% AOA. From all tested spectral transformations, only vegetation indices applied to the time series of multispectral images increased the performance. The results obtained with the hyperspectral image degraded to the specifications of Sentinel-2 emphasize the importance of fine spatial and spectral resolutions to achieve accurate mapping in this complex context. While no significant difference was found between impacted and reference sites through biodiversity metrics, vegetation mapping highlighted some differences in species distribution.

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Martínez-García, Ricardo, Justin M. Calabrese, Emilio Hernández-García, and Cristóbal López. "Minimal mechanisms for vegetation patterns in semiarid regions." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2027 (October 28, 2014): 20140068. http://dx.doi.org/10.1098/rsta.2014.0068.

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The minimal ecological requirements for the fomation of regular vegetation patterns in semiarid systems have been recently questioned. Against the general belief that a combination of facilitative and competitive interactions is necessary, recent theoretical studies suggest that, under broad conditions, non-local competition among plants alone may induce patterns. In this paper, we review results along this line, presenting a series of models that yield spatial patterns when finite-range competition is the only driving force. A preliminary derivation of this type of model from a more detailed one that considers water–biomass dynamics is also presented.

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Forzieri, Giovanni, Ramdane Alkama, Diego G. Miralles, and Alessandro Cescatti. "Response to Comment on “Satellites reveal contrasting responses of regional climate to the widespread greening of Earth”." Science 360, no. 6394 (June 14, 2018): eaap9664. http://dx.doi.org/10.1126/science.aap9664.

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Li et al. contest the idea that vegetation greening has contributed to boreal warming and argue that the sensitivity of temperature to leaf area index (LAI) is instead likely driven by the climate impact on vegetation. We provide additional evidence that the LAI-climate interplay is indeed largely driven by the vegetation impact on temperature and not vice versa, thus corroborating our original conclusions.

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Penížek, V., and T. Zádorová. "Soil toposequence under man-planted vegetation in the Krkonoše Mts., Czech Republic." Soil and Water Research 7, No. 4 (November 9, 2012): 138–50. http://dx.doi.org/10.17221/11/2012-swr.

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Mountainous areas represent regions with specific soil cover pattern that is naturally given by an altitudinal gradient. The objective of our study was to describe the soil cover development on the altitudinal gradient under changed environment given by man-planted vegetation and acidification. The studied area is characterized by spruce monoculture planting that replaced the original broadleaf natural vegetation and high load of anthropic acidification. The common hypothesis considering the sequence of Dystric Cambisol-Entic Podzol-Haplic Podzol with increasing altitude was not proved. The results of our study indicate that the influence of spruce vegetation causes the occurrence of Haplic Podzols at low altitudes where the natural soil formation does not induce their development. Results showed that the vegetation type can overrule other altitude-related soil-forming factors. The conversion of natural broadleaf and mixed forests to spruce monocultures leads to the expansion of podzolization process to lower altitudes.

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Feng, Dingrao, Meichen Fu, Yiyu Sun, Wenkai Bao, Min Zhang, Yafu Zhang, and Jinjin Wu. "How Large-Scale Anthropogenic Activities Influence Vegetation Cover Change in China? A Review." Forests 12, no. 3 (March 10, 2021): 320. http://dx.doi.org/10.3390/f12030320.

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Vegetation cover plays a key role in terrestrial ecosystem; therefore, it is important for researchers to investigate the variation and influencing factors of vegetation cover. China has experienced a large-scale vegetation cover change in recent years. We summarized the literature of vegetation cover change and revealed how large-scale anthropogenic activities influence vegetation cover change in China. Afforestation and intensification of cropland played a key role in large-scale greening. Urbanization showed a “U” shape to influence vegetation cover change. Mining and reclamation, land abandonment and land consolidation, and regional natural protection all had a unique influence on the change of vegetation cover. Indeed, the large-scale vegetation cover change was caused by interaction of anthropogenic factors and part human-driven climate change. Anthropogenic factors influenced climate change to indirectly alter the condition of plant growth. Interaction between climate change and human activities influence on vegetation cover still needs to be further investigated in the future.

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Dawes, Melissa A., Christopher D. Philipson, Patrick Fonti, Peter Bebi, Stephan Hättenschwiler, Frank Hagedorn, and Christian Rixen. "Soil warming and CO 2 enrichment induce biomass shifts in alpine tree line vegetation." Global Change Biology 21, no. 5 (January 30, 2015): 2005–21. http://dx.doi.org/10.1111/gcb.12819.

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Vogel, Sebastian, and Marco Conedera. "Effects of land use-induced vegetation and topography changes on soil chemistry in the Southern Alps (Ticino, Switzerland)." Plant, Soil and Environment 66, No. 2 (February 28, 2020): 73–80. http://dx.doi.org/10.17221/633/2019-pse.

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Effects of land use changes on chemical soil properties were studied in a southern alpine valley of Ticino, Switzerland by analysing three different land cover-topography units: (i) natural forested slopes (NFS); (ii) deforested, cultivated terraces (DCT), and (iii) reforested, abandoned terraces (RAT). Whereas NFS represents the natural reference state with negligible anthropogenic influence, DCT corresponds to intense agricultural utilization, and RAT refers to a post-cultural natural evolution after terrace cultivation. Land use-induced changes in vegetation cover and topography (i.e., terracing) had a clear influence on chemical soil properties. The presence or absence of the European chestnut (Castanea sativa Mill.), one of the main soil acidifying agents in the study area, clearly affected soil acidity, soil organic matter (SOM), and nutrient status. Compared to the vegetation change, terracing has a less obvious effect on soil chemistry. A greater effective rooting depth and a flat microtopography on terraces lead to a rapidly increased SOM accumulation due to better growing conditions for trees. Thus, the reforested, abandoned terraces develop peculiar soil chemistry conditions after 36 to 46 years of abandonment only.

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Li, Peng, Mai Sun, Yuxin Liu, Peixin Ren, Changhui Peng, Xiaolu Zhou, and Jiayi Tang. "Response of Vegetation Photosynthetic Phenology to Urbanization in Dongting Lake Basin, China." Remote Sensing 13, no. 18 (September 17, 2021): 3722. http://dx.doi.org/10.3390/rs13183722.

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Urbanization can induce environmental changes such as the urban heat island effect, which in turn influence the terrestrial ecosystem. However, the effect of urbanization on the phenology of subtropical vegetation remains relatively unexplored. This study analyzed the changing trend of vegetation photosynthetic phenology in Dongting Lake basin, China, and its response to urbanization using nighttime light and chlorophyll fluorescence datasets. Our results indicated the start of the growing season (SOS) of vegetation in the study area was significantly advanced by 0.70 days per year, whereas the end of the growing season (EOS) was delayed by 0.24 days per year during 2000–2017. We found that urbanization promoted the SOS advance and EOS delay. With increasing urbanization intensity, the sensitivity of SOS to urbanization firstly increased then decreased, while the sensitivity of EOS to urbanization decreased with urbanization intensity. The climate sensitivity of vegetation phenology varied with urbanization intensity; urbanization induced an earlier SOS by increasing preseason minimum temperatures and a later EOS by increasing preseason precipitation. These findings improve our understanding of the vegetation phenology response to urbanization in subtropical regions and highlight the need to integrate human activities into future vegetation phenology models.

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Tsiampousi, A., L. Zdravkovic, and D. M. Potts. "Numerical study of the effect of soil–atmosphere interaction on the stability and serviceability of cut slopes in London clay." Canadian Geotechnical Journal 54, no. 3 (March 2017): 405–18. http://dx.doi.org/10.1139/cgj-2016-0319.

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The stability of cut slopes is greatly influenced by seasonal pore-water pressure variations under the combined effect of rainfall and vegetation. However, predicting soil–atmosphere interaction is not straightforward, due to the complexity of both the boundary conditions involved and the hydromechanical behaviour of soils, which is coupled and highly nonlinear, rendering the use of numerical tools, such as finite element analysis, necessary. This paper discusses the numerical modelling of soil–atmosphere interaction and presents the analysis of a slope cut in London clay in a highly vegetated area. The whole life cycle of the slope is considered with phases of low and high water demand vegetation and vegetation clearance. The analysis results indicate that dense vegetation is associated with high factors of safety, but may induce large differential displacements, which are likely to affect the serviceability of the slope. Vegetation clearance, however, may initiate instability, highlighting the need for effective vegetation management to achieve a balance between serviceability and ultimate limit states. Although the case considered is representative of southeast England, it introduces the necessary tools for realistic numerical analysis of soil–atmosphere interaction.

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Li, Da, Zhonghua Yang, Junjie Zheng, Fangping Liu, and Gang Ge. "The Influence of Floodplain Vegetation Patches on Hydrodynamic Characteristics: A Case Study in the Old Course of Fuhe River." Nature Environment and Pollution Technology 21, no. 3 (September 1, 2022): 1073–85. http://dx.doi.org/10.46488/nept.2022.v21i03.013.

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As an important part of the river ecosystem, vegetation has a significant influence on hydrodynamic characteristics, water quality, river morphology, and ecological habitat. Combining vegetation survey with the verified numerical model, this study aims to analyze the impact of floodplain vegetation patches on hydrodynamic characteristics in the old course of Fuhe River under various combinations of incoming flow discharges, and flood diversion discharges, and changes in the land use type. The equivalent Manning coefficient was adopted to quantify the additional resistance induced by plants in the vegetation module of the numerical model. According to simulating results, vegetation patches would cause the water level to rise and velocity to decrease, which mainly affects the upstream of the old course of Fuhe River. And with the increase in incoming discharge, water level difference and velocity difference have an upward trend. It is also found that the resistance of Zizania latifolia to river flow is strongest followed by sugarcane, crops, and weeds because of the differences in vegetation characteristics. Furthermore, compared with existing vegetation conditions, converting farmland to Zizania latifolia and expanding farmland induce a moderate rise in water level upstream while the decreasing velocity happens in the area where land use type is changed. And there are areas where velocity increases located opposite to the velocity decreasing area because of the adjustment of cross-section velocity distribution caused by plants.

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Huang, F., D. H. Wen, and P. Wang. "VEGETATION CHANGES AND THE RELATIONSHIP WITH CLIMATE VARIABILITY IN THE UPPER AND MIDDLE REACHES OF THE NENJIANG RIVER BASIN, CHINA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (June 23, 2016): 889–95. http://dx.doi.org/10.5194/isprs-archives-xli-b8-889-2016.

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To detect changes in vegetation is desirable for modeling and predicting interactions between land surface and atmosphere. Multitemporal series of SPOT VEGETATION NDVI dataset and meteorological data were integrated to interpret vegetation dynamics and the linkage with climate variations in the upper and middle reaches of the Nenjiang River Basin (NRB) from 1999 to 2010 using the correlation analysis and the rescaled range (R/S) analysis. The results demonstrate that annual NDVI increased slightly and 26.02% vegetation coverage of the study area significantly improved. The area of significantly decreased in vegetation cover took up 13.33% of the total land in spring. In autumn, 26.2% of the study area showed a significant vegetation increase. The improved activity of vegetation might reinforce in summer and autumn, while the decreasing tendency in spring might be persistent in the future. The yearly NDVI had significant positive linkages with precipitation and relative humidity. NDVI related significantly and negatively with temperature, sunshine hours and wind velocity, because they may have effects of increasing evapotranspiration and risk of drought and cold damage of vegetation. The variations of annual NDVI were much affected by summer temperature, relative humidity and sunshine duration in autumn and spring wind velocity. Seasonal NDVI decreased in parallel with elevated temperature, but there was no correlation between NDVI and precipitation. Spring temperature, relative humidity in summer and autumn contributed markedly to NDVI variations in the same season. The vegetation improving trend may induce by the warm-wetting climate in recent twelve years.

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Huang, F., D. H. Wen, and P. Wang. "VEGETATION CHANGES AND THE RELATIONSHIP WITH CLIMATE VARIABILITY IN THE UPPER AND MIDDLE REACHES OF THE NENJIANG RIVER BASIN, CHINA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (June 23, 2016): 889–95. http://dx.doi.org/10.5194/isprsarchives-xli-b8-889-2016.

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To detect changes in vegetation is desirable for modeling and predicting interactions between land surface and atmosphere. Multitemporal series of SPOT VEGETATION NDVI dataset and meteorological data were integrated to interpret vegetation dynamics and the linkage with climate variations in the upper and middle reaches of the Nenjiang River Basin (NRB) from 1999 to 2010 using the correlation analysis and the rescaled range (R/S) analysis. The results demonstrate that annual NDVI increased slightly and 26.02% vegetation coverage of the study area significantly improved. The area of significantly decreased in vegetation cover took up 13.33% of the total land in spring. In autumn, 26.2% of the study area showed a significant vegetation increase. The improved activity of vegetation might reinforce in summer and autumn, while the decreasing tendency in spring might be persistent in the future. The yearly NDVI had significant positive linkages with precipitation and relative humidity. NDVI related significantly and negatively with temperature, sunshine hours and wind velocity, because they may have effects of increasing evapotranspiration and risk of drought and cold damage of vegetation. The variations of annual NDVI were much affected by summer temperature, relative humidity and sunshine duration in autumn and spring wind velocity. Seasonal NDVI decreased in parallel with elevated temperature, but there was no correlation between NDVI and precipitation. Spring temperature, relative humidity in summer and autumn contributed markedly to NDVI variations in the same season. The vegetation improving trend may induce by the warm-wetting climate in recent twelve years.

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Oliveira Neto, C. F., A. K. S. Lobato, R. C. L. Costa, W. J. M. S. Maia, B. G. Santos Filho, G. A. R. Alves, B. Brinez, H. K. B. Neves, M. J. Santos Lopes, and F. J. R. Cruz. "Nitrogen compounds and enzyme activities in sorghum induced to water deficit during three stages." Plant, Soil and Environment 55, No. 6 (July 16, 2009): 238–44. http://dx.doi.org/10.17221/84/2009-pse.

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The aim of this study was to evaluate and explicate the changes in the nitrogen compounds and enzyme activities in <I>Sorghum bicolor</I> plants (cv. BR-700) submitted to water deficit during vegetative, reproductive and maturation stages. The experimental design used was entirely randomized in factorial scheme, with two conditions (control and stress) combined with three stages (vegetative, reproductive and maturation). The nitrate level was increased at 180.6, 72.9 and 78.9% during the vegetative, reproductive and maturation stages, respectively. The total soluble amino acids and glycinebetaine increased only during vegetative and reproductive stages, if compared with control plants. However, besides protein levels during all stages, significant reductions were reported in nitrate reductase and glutamine synthetase activities; free ammonium presented decreases at 37.3 and 77.6% in vegetative and reproductive stages, respectively, when compared with control plants.

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Eni, D. D., A. I. Iwara, and R. A. Offiong. "Analysis of Soil-Vegetation Interrelationships in a South-Southern Secondary Forest of Nigeria." International Journal of Forestry Research 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/469326.

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Soil-vegetation interrelationships in a secondary forest of South-Southern Nigeria were studied using principal component analysis (PCA) and canonical correlation analysis (CCA). The grid system of vegetation sampling was employed to randomly collect vegetation and soil data from fifteen quadrats of 10 m × 10 m. PCA result showed that exchangeable sodium, organic matter, cation exchange capacity, exchangeable calcium, and sand content were the major soil properties sustaining the regenerative capacity and luxuriant characteristics of the secondary forest, while tree size and tree density constituted the main vegetation parameters protecting and enriching the soil for its continuous support to the vegetation after decades of anthropogenic disturbance (food crop cultivation and illegal logging activities) before its acquisition and subsequent preservation by the Cross River State government in 2003. In addition, canonical correlation analysis showed result similar to PCA, as it indicated a pattern of relationship between soil and vegetation. The only retained canonical variate revealed a positive interrelationship between organic matter and tree size as well as an inverse relationship between organic matter and tree density. These extracted soil and vegetation variables are indeed significantly important in explaining soil-vegetation interrelationships in the highly regenerative secondary forest.

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Liu, Guodong, Yuncong Li, Kimberly Moore, Kim Gabel, Lei Wu, and Rafael Muñoz-Carpena. "How to Chemigate Salinity-Stressed Plants with Hydrogen Peroxide to Increase Survival and Growth Rates." EDIS 2016, no. 3 (May 6, 2016): 3. http://dx.doi.org/10.32473/edis-hs1280-2016.

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Man-made activities can induce climate change and global sea-level rise, posing threats to the survival and growth of coastal vegetation in Florida. This 3-page fact sheet explains how to ensure plant survival and facilitate the growth of coastal vegetation threatened by sea-level rise and the resulting oxygen deficiencies and saline stresses. Written by Guodong Liu, Yuncong Li, Kimberly Moore, Kim Gabel, Lei Wu, and Rafael Muñoz-Carpena, and published by the Horticultural Sciences Department, April 2016. HS1280/HS1280: How to Chemigate Salinity-Stressed Plants with Hydrogen Peroxide to Increase Survival and Growth Rates (ufl.edu)

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Silva, Elisabeth Regina Alves Cavalcanti, José Gustavo Da Silva Melo, and Josiclêda Domiciano Galvincio. "Identificação das Áreas Susceptíveis a Processos de Desertificação no Médio Trecho da Bacia do Ipojuca - PE através do Mapeamento do Estresse Hídrico da Vegetação e da Estimativa do Índice de Aridez (Identification of Areas Susceptible to...)." Revista Brasileira de Geografia Física 4, no. 3 (September 25, 2011): 629. http://dx.doi.org/10.26848/rbgf.v4i3.232739.

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Este trabalho procura identificar as areas mais susceptiveis a processos de desertificacao na area correspondente ao medio trecho da Bacia do Ipojuca – PE, localizado no agreste do estado de Pernambuco, tomando como base dados obtidos de postos pluviometricos num periodo amostral de trinta anos com a finalidade de estimar o indice de aridez na area de estudo. Esse indice buscara complementar os resultados obtidos pelo indice de aridez atraves da utilizacao do indice de agua por diferenca normalizada (NDWI) e do indice de vegetacao ajustado ao solo (SAVI). Os resultados obtidos indicam que ha um alto estresse hidrico na Bacia em questao e esse resultado e corroborado pelo indice de aridez da area. Palavras-chaves: Suscetibilidade, mudancas climaticas, impactos ambientais, transposicao do Rio Sao Francisco. Identification of Areas Susceptible to Desertification in the Ipojuca Middle River Basin by Mapping of Vegetation Water Stress and Aridity Index ABSTRACT This paper seeks to identify areas susceptible to desertification in the area corresponding to the middle portion of the Basin Ipojuca - PE, located in the rugged state of Pernambuco, based on data from climatic stations in a sample period of thirty years for the purpose to estimate the index of aridity in the study area. This index will seek to complement the results obtained by the index of aridity by using the water content normalized difference (NDWI) and the vegetation index adjusted for soil (SAVI). The results indicate that there is a high water stress in the basin in question and this result is confirmed by the index of aridity of the area. Keywords: Susceptibility, climate change, environmental impacts, transposition of Rio Sao Francisco.

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Lotan, Tamar, Masa-aki Ohto, Kelly Matsudaira Yee, Marilyn A. L. West, Russell Lo, Raymond W. Kwong, Kazutoshi Yamagishi, Robert L. Fischer, Robert B. Goldberg, and John J. Harada. "Arabidopsis LEAFY COTYLEDON1 Is Sufficient to Induce Embryo Development in Vegetative Cells." Cell 93, no. 7 (June 1998): 1195–205. http://dx.doi.org/10.1016/s0092-8674(00)81463-4.

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Černý, Tomáš, Jiří Doležal, Petr Petřík, Miroslav Šrůtek, Jong-Suk Song, and Jan Altman. "Tropical Cyclone Disturbances Induce Contrasting Impacts on Forest Structure, Plant Composition, and Soil Properties in Temperate Broadleaf and Coniferous Forests." Forests 13, no. 7 (June 30, 2022): 1033. http://dx.doi.org/10.3390/f13071033.

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Knowledge of forest recovery processes after severe disturbances, such as tropical cyclones, is essential for understanding the mechanisms maintaining forest diversity and ecosystem functioning. However, studies examining the impact of tropical cyclones on forest dynamics are still rare, especially in Northeast Asia. Here, we explore the complex responses of vegetation and soil chemistry to severe tropical cyclone disturbances in Hallasan National Park in South Korea. Vegetation and soil were examined five years before and five years after passages of tropical cyclones in 2012 in natural broadleaf and coniferous forests along an elevation gradient from 950 to 1770 m a.s.l., including the largest population of endemic Abies koreana. Tropical cyclones caused abundant tree mortality, resulting in a 46% decrease in stem basal area. Tropical cyclone disturbances triggered the spread of pioneer trees and shrubs and intense clonal propagation of graminoids, including dwarf bamboo, resulting in less diverse understory vegetation, especially in coniferous forests. In contrast, broadleaf forests at lower elevations experienced only minor disturbance. Opening of canopies after tropical cyclone disturbance led to the decrease in soil cations and doubling of available soil phosphorus stock, which likely contributed to the increased coverage of clonal graminoids, especially in coniferous forests (from 36 to 66%). Hence, increased competition of graminoids and reduction in seed fall and seedling recruitment prevented A. koreana regeneration. The subalpine forest dominated by A. koreana is forecasted to gradual loss due to the fact of temperature increases, intensified tropical cyclones and, particularly, due to the altered competition between dwarf bamboo and fir seedlings.

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Mabuchi, Kazuo, Yasuo Sato, and Hideji Kida. "Climatic Impact of Vegetation Change in the Asian Tropical Region. Part I: Case of the Northern Hemisphere Summer." Journal of Climate 18, no. 3 (February 1, 2005): 410–28. http://dx.doi.org/10.1175/jcli-3273.1.

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Abstract Several numerical simulations were performed, using a global climate model that includes a realistic land surface model, to investigate the impact of Asian tropical vegetation changes on the climate. The control simulation, under conditions of the actual vegetation, and three vegetation-change impact experiments were performed. The results of the impact experiments were compared with those of the control simulation. The horizontal resolution of the model used in these simulations was 1.875°, being finer than that of the models used in previous vegetation-change impact studies. As a result, it was determined that the effects of vegetation changes in the Asian tropical region had spatially different features. The morphological, physiological, and physical changes of the land surface vegetation in the Asian tropical region certainly induce statistically significant climate changes in these and the surrounding areas. That is, from the results of the bare soil and C4 grass experiments, the decrease in the roughness length, and from the results of the green-less experiment, the decrease of the latent heat flux, exert strong influences on the horizontal and convective circulations of the atmosphere. Consequently, the distribution of precipitation will undergo a change. Other energy and water balances at the land surface are also influenced by the vegetation changes, and the induced changes are generally statistically significant. The influences of vegetation changes in the Asian tropical region were more complicated than those in the Amazon. One reason for this was that the Asian tropical region is strongly influenced by the Asian monsoon circulation; another reason is that the land–sea distribution and the distribution of vegetation in the Asian tropical region are not as simple as in a tropical rain forest like the Amazon.

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Journal articles on the topic 'Vegetation indece'

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