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LANDSCAPE ECOLOGICAL METHOD TO STUDY AGRICULTURAL VEGETATION: SOME EXAMPLES FROM THE PO VALLEY  

Directory of Open Access Journals (Sweden)

Full Text Available Vegetation is the most important landscape component, as regards to its ability to catch solar energy and to transform it, but also to shape the landscape, to structure the space, to create the fit environment for different animal species, to contribute to the maintenance of a correct metastability level for the landscape, etc. It is a biological system which acts under the constraints of the principles of the System Theory and owns the same properties of any other living system: so, it is a complex adaptive, hierarchical, dynamic, dissipative, self-organizing, self-transcendent, autocatalytic, self-maintaining system and follows the non-equilibrium thermodynamic. Its ecological state can be investigated through the comparison between “gathered data” (pathology and “normal data” (physiology for analogous types of vegetation. The Biological Integrated School of Landscape Ecology provides an integrated methodology to define ecological threshold limits of the different Agricultural Landscape types and applies to agricultural vegetation the specific part of the new methodology already tested to studying forests (the Landscape Biological Survey of Vegetation. Ecological quality, better and worst parameters, biological territorial capacity of vegetated corridors, agricultural field, poplar groves, orchards and woody remnant patches are investigated. Some examples from diverse agricultural landscapes of the Po Valley will be discussed. KEY WORDS: agricultural landscape, vegetation, landscape ecology, landscape health, Biological Integrated Landscape Ecology, Landscape Biological Survey of vegetation.

E. GIGLIO

2006-01-01

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Market perspectives for ecological products (vegetables) in Lithuania  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Market perspectives for ecological products (vegetables) in Lithuania in regard to consumers opinion is presented in this master thesis. Pros and cons of ecological farming as well as distinctiveness of products produced by means of ecological farming are analyzed. Research hypothesis – consumption culture, variety of choices and the other factors having impact on ecological products market perspectives proved to be accurate. Conclusions are presented as well as recommendations suggested on...

Blankaite?, Vaida; Natus?aityte?, Vita

2009-01-01

3

A test of ecological optimality for semiarid vegetation. M.S. Thesis  

Science.gov (United States)

Three ecological optimality hypotheses which have utility in parameter reduction and estimation in a climate-soil-vegetation water balance model are reviewed and tested. The first hypothesis involves short term optimization of vegetative canopy density through equilibrium soil moisture maximization. The second hypothesis involves vegetation type selection again through soil moisture maximization, and the third involves soil genesis through plant induced modification of soil hydraulic properties to values which result in a maximum rate of biomass productivity.

Salvucci, Guido D.; Eagleson, Peter S.; Turner, Edmund K.

1992-01-01

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The vegetation of Yucca Mountain: Description and ecology  

Energy Technology Data Exchange (ETDEWEB)

Vegetation at Yucca Mountain, Nevada, was monitored over a six-year period, from 1989 through 1994. Yucca Mountain is located at the northern limit of the Mojave Desert and is the only location being studied as a potential repository for high-level nuclear waste. Site characterization consists of a series of multidisciplinary, scientific investigations designed to provide detailed information necessary to assess the suitability of the Yucca Mountain Site as a repository. This vegetation description establishes a baseline for determining the ecological impact of site characterization activities; it porvides input for site characterization research and modeling; and it clarifies vegetation community dynamics and relationships to the physical environment. A companion study will describe the impact of site characterization of vegetation. Cover, density, production, and species composition of vascular plants were monitored at 48 Ecological Study Plots (ESPs) stratified in four vegetation associations. Precipitation, soil moisture, and maximum and minimum temperatures also were measured at each study plot.

NONE

1996-03-29

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Ecological investigations: vegetation studies, preliminary findings  

Energy Technology Data Exchange (ETDEWEB)

The objective of the vegetation studies conducted on the research site is to produce a descriptive data base that can be applied to determinations of carrying capacity of the site and surrounding area. Additional information obtained about parameters that influence vegetation growth and maintenance of soil nutrients, and moisture and temperature regimes help define dynamic relationships that must be understood to effect successful revegetation and habitat rehabilitation. The descriptive vegetation baseline also provides a point of departure for design of future monitoring programs, and predictive models and strategies to be used in dealing with impact mitigation; in turn, monitoring programs and predictive modeling form the bases for making distinctions between natural trends and man-induced perturbations.

Olgeirson, E.R.; Martin, R.B.

1978-09-01

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Effect of stand types on understory vegetation.  

Science.gov (United States)

The objective of this study was to compare density vegetative cover, basal area, height growth, aboveground biomass production, frequency floristic composition, and species diversity of understory vegetation growing in Hungarian oak (Quercus frainetto Ten.), Oriental beech (Fagus orientalis L.) and a mixed stand of both species (90% Hungarian oak and 10% Oriental beech) with the same crown closure. Understory vegetation was sampled with a quadrat of 0.5 m x 1 m along the 25 m-long transect lines in each stand. A total of seventeen perennial plant species from thirteen different families were found in the three stand types and all of them were present in Hungarian oak stand, eleven in Oriental beech stand, and seven in the mixed stand of Hungarian oak and Oriental beech trees. Results showed that stand types had a statistically significant effect on density, vegetative cover, basal area, height growth, biomass production, frequency floristic composition, and species diversity of understory vegetation. Total understory vegetation density was the highest for Hungarian oak stand with about 136 plants m(-2) and the lowest for the mixed stand of Hungarian oak and Oriental beech with 44 plants m(-2). In addition, the Hungarian oak stand had the most diverse understory vegetation with about 4.3 different plant m(-2), followed by the Oriental beech stand with 3.7 plants m(-2), and the mixed stand of the Hungarian oak and Oriental beech with 2.7 plants m(-2). Species density and diversity were the highest in Hungarian oak stand whereas aboveground biomass production and height growth of understory vegetation were highest in the mixed stand. PMID:20120502

Ister, Sena I; Gokbulak, Ferhat

2009-07-01

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Alternative Ecology of Human Pathogenic Bacteria in Fruits and Vegetables  

Directory of Open Access Journals (Sweden)

Full Text Available Outbreaks of illness due to human enteric pathogenic bacteria via fresh vegetables warrant intensive research on changing strategies of these bacteria in alterning their hosts for survival. The systemic infection of human pathogenic bacteria in plants and the plant growth stage at which they establish endophytic relationship is poorly understood. The issue is magnified in countries like India where the dietary habits are changing and consumption of fresh fruits and vegetables as salad has become a part in the everyday menu of most people. Most of the human pathogenic enteric bacteria are generally characterized by broad host ranges and these pathogens seem to exploit almost any change in human ecology that provides new opportunities for transmission. Because plants are not traditionally considered as hosts for human enteric pathogens, recent produce-associated outbreaks highlight important deficiencies in our understanding of the ecology of enteric pathogens outside of their human and animal hosts. This review focuses on understanding the human enteric pathogens that have developed abilities to colonize internal tissues of vegetables and fruits popularly consumed as salads, how and when do they enter plants and where do they localize in plant tissues. In addition, we have also highlighted the attempts made in detection and control of these bacteria in plant hosts. This understanding will help develop strategies towards vegetable food safety in a joint effort by agriculturalists, environmentalists, food processing agencies, whole salers and retailers, which will ultimately benefit every consumer.

A. Nithya

2014-01-01

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PROPOSAL OF A NEW METHOO OF ECOLOGICAL EVALUATION OF VEGETATION: THE CASE STUDY OF THE VEGETATION OF THE VENICE LAGOON LANDSCAPE ANO OF ITS SALT MARSHES  

Directory of Open Access Journals (Sweden)

Full Text Available

In frequent case studies, the heterogeneity of vegetation formation is very high, because of the frequency of both natural and human disturbances. Consequently, the phytosociological approach .and the auto-ecological one are not completely adequate for the evaluation or the ecological state of this vegetation in a landscape.

So, this evaluation needs the integration with a landscape ecological method of vegetation survey through schedules, as indicated by Ingegnoli (2002. Each type of schedule has been designed to check the organisation level and to estimate the metastability of a tessera of a certain type of vegetation, considering both general ecological and landscape ecological characters: (A Landscape e1ement characters (e.g. tessera, corridor, (8 Plant, biomass above ground, (C Ecocoenotope pararneters. (D Relation among the elements and their landscape parameters. There are four evaluation classes, the weights per class depending on an evaluation model designed as shown later on. The principal aim of this research is to design a new schedule, available for the main coenosis of salt marshes vegetation, which allows to complete a preliminary study on the Venice lagoon landscape dynamics, based on its vegetation. The landscape of the Venice lagoon is very complex and articulated, its main vegetation formations are the following: Underwater, Salt marshes. Littoral. Reclamation colonisations, Wet areas. Wooded patches and corridors. Agricultural cultivations, Urban green. The most important typc of vegetation is represented by salt marshes prairies called "barene", especially by Limonietum venetum (Pignani. 1966, This association can be divided into three sub-associations, the first with three facies: but the reality presents a large quantity of tesserae in intermediate or ecotonal states, even mixed with other associations (e,g, Spartinetum maritimae. The design and control of the schedule, the first measure of the community plant biomasses are a part of this study, me results of which will be discussed in this work.

E. GIGLIO

2004-01-01

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Arctic Ecological Classifications Derived from Vegetation Community and Satellite Spectral Data  

Directory of Open Access Journals (Sweden)

Full Text Available As a result of the warming observed at high latitudes, there is significant potential for the balance of ecosystem processes to change, i.e., the balance between carbon sequestration and respiration may be altered, giving rise to the release of soil carbon through elevated ecosystem respiration. Gross ecosystem productivity and ecosystem respiration vary in relation to the pattern of vegetation community type and associated biophysical traits (e.g., percent cover, biomass, chlorophyll concentration, etc.. In an arctic environment where vegetation is highly variable across the landscape, the use of high spatial resolution imagery can assist in discerning complex patterns of vegetation and biophysical variables. The research presented here examines the relationship between ecological and spectral variables in order to generate an ecologically meaningful vegetation classification from high spatial resolution remote sensing data. Our methodology integrates ordination and image classifications techniques for two non-overlapping Arctic sites across a 5° latitudinal gradient (approximately 70° to 75°N. Ordination techniques were applied to determine the arrangement of sample sites, in relation to environmental variables, followed by cluster analysis to create ecological classes. The derived classes were then used to classify high spatial resolution IKONOS multispectral data. The results demonstrate moderate levels of success. Classifications had overall accuracies between 69%–79% and Kappa values of 0.54–0.69. Vegetation classes were generally distinct at each site with the exception of sedge wetlands. Based on the results presented here, the combination of ecological and remote sensing techniques can produce classifications that have ecological meaning and are spectrally separable in an arctic environment. These classification schemes are critical for modeling ecosystem processes.

David M. Atkinson

2012-12-01

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NUTRITIONAL STATE OF ECOLOGICAL VEGETABLES IN DROUGHT CONDITIONS  

Directory of Open Access Journals (Sweden)

Full Text Available The contents of mineral nutritional elements in vegetables’ leaves were studied in an ecologically assessed field at the Research-Development Station for Vegetables (SCDL Bac?u, on a Fluvisol, in 2006 and 2007. Soil texture is sandyloamy, pH 6.2-6.8, and the humus content 2.4-2.6%. Vegetables have been grown here for several tens of years. In the last years, in an ecological agriculture system, the soil has been fertilized only with farm-made compost and green manure. Organic fertilization didn’t significantly improve the nutritive elements soil contents but it had the merit to preserve the soil fertility properties, along with the natural equilibrium between nutritional elements. Under these conditions, lower total nitrogen contents were determined in tomato leaves and higher in egg-plant leaves. Phosphorus contents proved to be relatively constant with egg-plants and a little lower with tomatoes; potassium and calcium contents were much lower with tomatoes; zinc and copper contents registered depletions, both for egg-plants and tomatoes, the iron contents slightly increased, while manganese contents remained relatively constant. In 2007 the potassium contents in tomatoes leaves shifted towards the critical domain, as compared to the lower limit of the excessive domain in 2006, in egg-plants leaves it remained under this domain limit, as in 2006; the calcium contents remained in the excessive domain, as in 2006, the magnesium contents shifted towards the critical domain, as compared to the normal one in 2006, iron contents remained excessive for tomatoes; the zinc remained in the normal content domain for tomatoes, as in 2006, and decreased to the critical domain for egg-plants; the copper remained in the excessive content domain, but at the inferior limit of it, unlike in 2006. Due to these modifications of ratios between the mineral nutritional elements absorbed in leaves in 2007 the cellular sap pH values were lower than in 2006.

Mihaela Lungu

2008-10-01

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Effects of aquatic vegetation type on denitrification  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In a microcosm 15N enrichment experiment we tested the effect of floating vegetation (Lemna sp.) and submerged vegetation (Elodea nuttallii) on denitrification rates, and compared it to systems without macrophytes. Oxygen concentration, and thus photosynthesis, plays an important role in regulating denitrification rates and therefore the experiments were performed under dark as well as under light conditions. Denitrification rates differed widely between treatments, ranging from 2.8 to 20.9 ?...

Veraart, A. J.; Bruijne, W. J. J.; Peeters, E. T. H. M.; Klein, J. J. M.; Scheffer, M.

2011-01-01

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[Succession pattern of artificial vegetation community and its ecological mechanism in an arid desert region].  

Science.gov (United States)

Focusing on the artificial vegetation protection system of the Shapotou section of Baotou-Lanzhou railway in the arid desert region of China, this paper examined the dynamics of dominant plant species and the succession pattern of artificial plant community in the process of establishing and developing regional artificial vegetation. It also studied the driving force and the ecologically intrinsic mechanism of the community succession. The results demonstrated that the species composition of the artificial vegetation dramatically changed after 40 years of succession, from original artificial plant community of shrub and semi-shrub to artificial-natural desert plant community with annual herb dominated. During the process of succession, the importance values of artificial shrubs, such as Caragana korshinskii and Hedysarum scoparius, decreased and gradually retreated from the artificial plant community, while the naturally multiplied annual herb, such as Eragrostis poaeoides, Bassia dasyphylla, Salsola ruthenica, Chloris virgata and etc., were presented one after another and gradually became dominant. Besides, Artemisia ordosica always played a key role in the community due to its ability of naturally sowing and self-replacement. This type of succession pattern was closely related to the shortage of precipitation resource in this region and the formation of soil crust which inhibited the reproduction of shrub and perennial herb with deep root systems. This study provided a theoretical ground for realizing persistent development of artificial plant community. PMID:14732997

Xu, Cailin; Li, Zizhen

2003-09-01

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Future vegetation types and related main processes for Olkiluoto site  

International Nuclear Information System (INIS)

This working report summarizes current knowledge of the land up-lift induced vegetation succession and future vegetation types on Olkiluoto Island and its surroundings. The report is based on generic literature and site-specific studies concerning Olkiluoto Island. Current vegetation on Olkiluoto Island and typical succession lines on different soil types are described, as well as main factors affecting the succession. Most relevant materials on hand are listed. Some problems and possible areas to be emphasized before using the data in modelling work are pointed out. (orig.)

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Classification of simple vegetation types using POLSAR image data  

Science.gov (United States)

Mapping basic vegetation or land cover types is a fairly common problem in remote sensing. Knowledge of the land cover type is a key input to algorithms which estimate geophysical parameters, such as soil moisture, surface roughness, leaf area index or biomass from remotely sensed data. In an earlier paper, an algorithm for fitting a simple three-component scattering model to POLSAR data was presented. The algorithm yielded estimates for surface scatter, double-bounce scatter and volume scatter for each pixel in a POLSAR image data set. In this paper, we show how the relative levels of each of the three components can be used as inputs to simple classifier for vegetation type. Vegetation classes include no vegetation cover (e.g. bare soil or desert), low vegetation cover (e.g. grassland), moderate vegetation cover (e.g. fully developed crops), forest and urban areas. Implementation of the approach requires estimates for the three components from all three frequencies available using the NASA/JPL AIRSAR, i.e. C-, L- and P-bands. The research described in this paper was carried out by the Jet Propulsion Laboratory, California Institute of Technology under a contract with the National Aeronautics and Space Administration.

Freeman, A.

1993-01-01

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ECOLOGICAL CONTROL EQUIPMENT AND TECHNOLOGY OF UNDERWATER VEGETATION DEVELOPMENT  

Directory of Open Access Journals (Sweden)

Full Text Available The excess of aquatic submerse vegetation development carries to the reduction of the real rearing area for the piscicultural material from the production farms and allow nestling of the ichthyophages bird species that decrease the fish production. Aquatic submerse vegetation stumble the utilization of aquatic zones for recreation and also wright function of basins utilized for the electric energy production, of micro electricity works through obstruction of the dams grid. The control of the aquatic submerse vegetation development, for Myriophyllum verticillatum, Ceratophyllum submersum, Urticularia vulgaris, Potamogeton natans, Nimphoides peltata species it is accomplish through the removing of some parts of these, preferably with all the stump system. Usually, these its accomplish with the floating equipments fit up with the thermic engines and the propulsion and governating elements who have harm over the fish and some others aquatic organisms through the noise, the displacing a large quality of water caused of propulsion systems and through the noxes elimination (flue, carburant trails, etc.. These technologies reside from the evacuation of the aquatic submerse vegetation and the stump systems of these with the help of an adjustable rake, hang up from the coast by a rope, wrapped to a drummer, who is trained by a motto-propeller group with a small installed power.

V. TITINSCHNEIDER

2013-12-01

16

Alternative Ecology of Human Pathogenic Bacteria in Fruits and Vegetables  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Outbreaks of illness due to human enteric pathogenic bacteria via fresh vegetables warrant intensive research on changing strategies of these bacteria in alterning their hosts for survival. The systemic infection of human pathogenic bacteria in plants and the plant growth stage at which they establish endophytic relationship is poorly understood. The issue is magnified in countries like India where the dietary habits are changing and consumption of fresh fruits ...

Nithya, A.; Gothandam, K. M.; Babu, S.

2014-01-01

17

Alternatives to sowing vegetable type soybeans  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Today, soybean crops of the Tamba Kurodaisu cultivar are sown in beds prior to transplantation to the field. This planting system has caused crop failure due to damage to the root system. An experiment to test different sowing alternatives to obtain plantlets for cropping of food type big seeded soybean was set up with the following treatments: sowing in beds; sowing in 130 cm³ newspaper cups; sowing in test tubes of volumes of 30 cm³, 60 cm³ and 70 cm³; sowing in 70 cm³ disposable plast...

Edcarlos Mannfredini; Deonisio Destro; Martin Homechin; Gustavo Sachsida; Édison Miglioranza

1998-01-01

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Emergence of Indigenous Vegetation Classifications Through Integration of Traditional Ecological Knowledge and Remote Sensing Analyses  

Science.gov (United States)

Traditional ecological knowledge (TEK) can play an important role in the understanding of ecological systems. Although TEK has complemented scientific and managerial programs in a variety of contexts, its formal incorporation into remote sensing exercises has to date been limited. Here, we show that the vegetation classifications of the Ache, an indigenous hunter-gatherer tribe of the Mbaracayu Forest Reserve in Paraguay, are reflected in a supervised classification of satellite imagery of the reserve. Accuracy of classification was toward the low end of the range of published values, but was reasonable given the difficult nature of separating forest classes from satellite images. Comparison of the resultant map with a more traditionally elaborated vegetation map highlights differences between the two approaches and the gain in information obtained by considering TEK classifications. We suggest that integration of TEK and remote sensing may provide alternative insights into the ecology of vegetation communities and land cover, particularly in remote and densely forested areas where ecological field research is often limited by roads and/or trail systems.

Naidoo, Robin; Hill, Kim

2006-09-01

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Nemunas Loops Regional Park the forest of Punia woody vegetation ecological assessment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Post–graduate work examined the Nemunas loops regional park the forest of Punia woody vegetation. Object of the work - forest of Punia with nature reserve and botanical - zoological preserve that are in it. Now forest of Punia - one of the most important part of the Nemunas Loops Regional Park. Aim of the work - the ecological assessment of Nemunas loops regional park forest of Punia woody vegetation. Method of the work - analysis of literary material and on the basis of the Nemunas Loops R...

Gudaitis, Marius

2009-01-01

20

Vegetation  

DEFF Research Database (Denmark)

• Over the past 30 years (1982-2011), the Normalized Difference Vegetation Index (NDVI), an index of green vegetation, has increased 15.5% in the North American Arctic and 8.2% in the Eurasian Arctic. In the more southern regions of Arctic tundra, the estimated aboveground plant biomass has increased 20-26%. • Increasing shrub growth and range extension throughout the Low Arctic are related to winter and early growing season temperature increases. Growth of other tundra plant types, including graminoids and forbs, is increasing, while growth of mosses and lichens is decreasing. • Increases in vegetation (including shrub tundra expansion) and thunderstorm activity, each a result of Arctic warming, have created conditions that favor a more active Arctic fire regime.

Epstein, H.E.; Walker, D.A.

2012-01-01

 
 
 
 
21

Alternatives to sowing vegetable type soybeans  

Directory of Open Access Journals (Sweden)

Full Text Available Today, soybean crops of the Tamba Kurodaisu cultivar are sown in beds prior to transplantation to the field. This planting system has caused crop failure due to damage to the root system. An experiment to test different sowing alternatives to obtain plantlets for cropping of food type big seeded soybean was set up with the following treatments: sowing in beds; sowing in 130 cm³ newspaper cups; sowing in test tubes of volumes of 30 cm³, 60 cm³ and 70 cm³; sowing in 70 cm³ disposable plastic cups; sowing on 90 cm³ styrofoam trays. A randomized complete block design was used, and the following traits were assessed: germination percentage; number of days to flowering; plant height at flowering; number of days to maturity; plant height at maturity; number of seeds per plant; individual plant yield; weight of a hundred seeds. Results should that three methods could be used to set up Tamba Kurodaisu cultivar crops: sowing in disposable plastic cups, sowing in beds with later transplant, or direct sowing in the field.Atualmente, as lavouras com o cultivar Tamba Kurodaisu são semeadas em canteiros, para posterior transplante no campo. Este sistema tem causado falhas na lavoura, por ocorrer danificação no sistema radicular. Com o objetivo de testar diferentes alternativas de semeadura para obtenção de mudas visando a implantação de lavouras de soja tipo alimento, com sementes graúdas, instalou-se um experimento com os seguintes tratamentos: Semeadura em canteiros; Semeadura em copos de jornal, com volume (V igual a 130 cm³; Semeadura em tubetes, com V = 30 cm³; V = 60 cm³; V = 70 cm³; Semeadura em copos plásticos descartáveis, com V = 70 cm³; Semeadura em bandejas de isopor, com V = 90cm³. O delineamento utilizado foi blocos casualizados, tendo sido avaliados os seguintes caracteres: Porcentagem de germinação; Número de plantas por parcela; Número de dias para o florescimento; Altura da planta no florescimento; Número de dias para a maturidade; Altura da planta na maturidade; Número de sementes por planta; Produtividade por planta individual; Peso de cem sementes. Para implantar as lavouras de soja com o cultivar Tamba Kurodaisu, pode se utilizar três maneiras: semeadura em copos plásticos descartáveis ou semeadura em canteiros com posterior transplantio e semeadura direta no campo.

Edcarlos Mannfredini

1998-08-01

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Alternatives to sowing vegetable type soybeans  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Atualmente, as lavouras com o cultivar Tamba Kurodaisu são semeadas em canteiros, para posterior transplante no campo. Este sistema tem causado falhas na lavoura, por ocorrer danificação no sistema radicular. Com o objetivo de testar diferentes alternativas de semeadura para obtenção de mudas visand [...] o a implantação de lavouras de soja tipo alimento, com sementes graúdas, instalou-se um experimento com os seguintes tratamentos: Semeadura em canteiros; Semeadura em copos de jornal, com volume (V) igual a 130 cm³; Semeadura em tubetes, com V = 30 cm³; V = 60 cm³; V = 70 cm³; Semeadura em copos plásticos descartáveis, com V = 70 cm³; Semeadura em bandejas de isopor, com V = 90cm³. O delineamento utilizado foi blocos casualizados, tendo sido avaliados os seguintes caracteres: Porcentagem de germinação; Número de plantas por parcela; Número de dias para o florescimento; Altura da planta no florescimento; Número de dias para a maturidade; Altura da planta na maturidade; Número de sementes por planta; Produtividade por planta individual; Peso de cem sementes. Para implantar as lavouras de soja com o cultivar Tamba Kurodaisu, pode se utilizar três maneiras: semeadura em copos plásticos descartáveis ou semeadura em canteiros com posterior transplantio e semeadura direta no campo. Abstract in english Today, soybean crops of the Tamba Kurodaisu cultivar are sown in beds prior to transplantation to the field. This planting system has caused crop failure due to damage to the root system. An experiment to test different sowing alternatives to obtain plantlets for cropping of food type big seeded soy [...] bean was set up with the following treatments: sowing in beds; sowing in 130 cm³ newspaper cups; sowing in test tubes of volumes of 30 cm³, 60 cm³ and 70 cm³; sowing in 70 cm³ disposable plastic cups; sowing on 90 cm³ styrofoam trays. A randomized complete block design was used, and the following traits were assessed: germination percentage; number of days to flowering; plant height at flowering; number of days to maturity; plant height at maturity; number of seeds per plant; individual plant yield; weight of a hundred seeds. Results should that three methods could be used to set up Tamba Kurodaisu cultivar crops: sowing in disposable plastic cups, sowing in beds with later transplant, or direct sowing in the field.

Edcarlos, Mannfredini; Deonisio, Destro; Martin, Homechin; Gustavo, Sachsida; Édison, Miglioranza.

1998-08-01

23

Ecological physiological characteristic of some species of natural vegetation in the Poles'e State Radiation Ecological Reservation  

International Nuclear Information System (INIS)

Influence of radiation on important ecological and physiological characteristics of Pinus silvestris L., Phleum pratense L. and Dactylis glomerata L. growing on territory of the Poles'e State Radiation Ecological Reservation has been investigated in 1992-1994. Significant changes in species and quantitative formation of natural vegetation growing on territory contaminated by the Chernobyl accident release were not observed. Positive correlation between the content of protein in needles of Pinus silvestris L., leaves of Agropyron repens L. and specific radioactivity of photosystem was established. Positive correlation between specific radioactivity of overground photosystem and quantity of nucleic acids (DNA+RNA) is leaves of Dactylis glomerata was found. 8 refs., 2 tabs., 2 figs

24

The integration of GPS, vegetation mapping and GIS in ecological and behavioural studies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Global Positioning System (GPS) satellite navigation receivers are increasingly being used in ecological and behavioural studies to track the movements of animals in relation to the environments in which they live and forage. Concurrent recording of the animal's foraging behaviour (e.g. from jaw movement recording) allows foraging locations to be determined. By combining the animal GPS movement and foraging data with habitat and vegetation maps using a Geographical Information System (GIS) it...

Steven Mark Rutter

2007-01-01

25

Comparison of total polyphenol contents And antioxidant activity in cruciferous vegetables grown in diversified ecological conditions  

Directory of Open Access Journals (Sweden)

Full Text Available Background.The aim of this study was to compare total polyphenol contents and antioxidant activity of three species of cruciferous vegetables grown under diversified ecological conditions for three consecutive years. Material and methods. Methanol extracts were prepared to be used to determine (spectrometrically the content of total phenolics, using the Folin-Ciocalteau reagent and antioxidant activity by identifying the sam- ple’s ability to extinguish an ABTS•+free radical. Results.All these species of cruciferous vegetables contained similar total polyphenols amounts regardless of its origin. Only red cabbage from organic farms was characterized by significantly higher antioxidant activity compared to vegetables purchased from local retailers in Cracow and similar or those cultivated near the steelworks. In white cabbage from farms located in a former steelworks protection zone a higher antioxidant activity was found than in organically grown vegetables and similar to that in vegetables available in retail. Brussels sprouts was characterised by a similar antioxidant activity regardless of its origin. Conclusions. On the basis of the present study, it cannot be concluded that organically grown cruciferous vegetables generally have higher contents of health-promoting secondary metabolites in comparison with the conventionally cultivated ones.

Joanna Kapusta-Duch

2012-12-01

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The ecological variations in thermal infrared emissivity of vegetation. [in Texas, Arizona, New Mexico, and Mexico  

Science.gov (United States)

The author has identified the following significant results. Through a series of contrasts, the statistical significance of differences in emissivity was determined for vegegation in dry and humid deserts, montane and deciduous rain forests, and the temperate region. No significant differences were found between the two types of desert vegetation or among the types of nondesert vegetation. However, the rain forest vegetation was significantly different from that of the temperate region. On a community-wide level, there is some physiological adaptation in plants to their radiational environment.

Arp, G. K.; Phinney, D. E. (principal investigator)

1979-01-01

27

Vegetation survey: a new focus for Applied Vegetation Science  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation survey is an important research agenda in vegetation science. It defines vegetation types and helps understand differences among them, which is essential for both basic ecological research and applications in biodiversity conservation and environmental monitoring. In this editorial, we reflect on the historical development and current state of vegetation survey worldwide and introduce the Special Feature ‘Vegetation Survey’, as well as the new section of the same name in Applie...

Chytry, M.; Schaminee, J. H. J.; Schwabe, A.

2011-01-01

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Using ecological forecasting of future vegetation transition and fire frequency change in the Sierra Nevada to assess fire management strategies  

Science.gov (United States)

Ecological systems may respond in complex manners as climate change progresses. Among the responses, site-level climate conditions may cause a shift in vegetation due to the physiological tolerances of plant species, and the fire return interval may change. Natural resource managers challenged with maintaining ecosystem health need a way to forecast how these processes may affect every location, in order to determine appropriate management actions and prioritize locations for interventions. We integrated climate change-driven vegetation type transitions with projected change in fire frequency for 45,203 km2 of the southern Sierra Nevada, California, containing over 10 land management agencies as well as private lands. This Magnitude of Change (MOC) approach involves classing vegetation types in current time according to their climate envelopes, and identifying which sites will in the future have climates beyond what that vegetation currently occurs in. Independently, fire models are used to determine the change in fire frequency for each site. We examined 82 vegetation types with >50 grid cell occurrences. We found iconic resources such as the giant sequoia, lower slope oak woodlands, and high elevation conifer forests are projected as highly vulnerable by models that project a warmer drier future, but not as much by models that project a warmer future that is not drier than current conditions. Further, there were strongly divergent vulnerabilities of these forest types across land ownership (National Parks versus US Forest Service lands), and by GCM. For example, of 50 giant sequoia (Sequoiadendron giganteum) groves and complexes, all but 3 (on Sierra National Forest) were in the 2 highest levels of risk of climate and fire under the GFDL A2 projection, while 15 groves with low-to-moderate risk were found on both the National Parks and National Forests 18 in the 2 under PCM A2. Landscape projections of potential MOC suggest that the region is likely to experience strong upslope shifting of open grassland, chaparral and hardwood types, which may be initiated by increased fire frequencies, particularly where fires have not recently burned within normal fire recurrence interval departures (FRID). An evaluation of four fire management strategies (business as usual; resist change; foster orderly change; protect vital resources) across four combinations of future climate and fire frequency found that no single management strategy was uniformly successful in protecting critical resources across the range of future conditions examined. This limitation is somewhat driven by current management constraints on the amount of management available to resource managers, which suggests management will need to use a triage approach to application of proactive fire management strategies, wherein MOC landscape projections can be used in decision support.

Thorne, J. H.; Schwartz, M. W.; Holguin, A. J.; Moritz, M.; Batllori, E.; Folger, K.; Nydick, K.

2013-12-01

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[Organochlorine pesticide residues in 4 types of vegetable oils].  

Science.gov (United States)

The present study had as objectives to identify and to quantify organochlorine pesticide residues (OCP) hexachlorobenzene (HCB), lindane, cis-chlordane, heptachlor, aldrin, dieldrin, endrin and o,p'-DDT in vegetable oils of corn, soybean, sunflower and mixtures of oils, sold in the city of Maracaibo, Venezuela. 30 samples of 4 types of vegetable oils of 10 commercial brands were analyzed. The extraction of OCP residues was done according to the Official Method of AOAC. A gas chromatograph with an electronic capture detector (GC-ECD) was used for identification and quantification of OCP residues and confirmation was done with a gas chromatograph coupled with a mass spectrometer (GC-MS). All the OCP residues investigated were detected in the analyzed samples. Aldrin (0.0088), lindane (0.0054) and o,p'-DDT (0.0035) were the OCP residues detected in higher concentrations (microg/g). The statistical analysis showed significant differences (Poils. Lindane concentration in the corn oil (0.0125 microg/g), as well as cischlordane (0.0091 microg/g) and aldrín (0.0287 microg/g) in the soybean oil exceeded maximal residual limits (MRL) established by Food and Agriculture Organization of the United Nations/World Health Organization (FAO/WHO). In conclusion, it was detected a high incidence of OCP residues in vegetable oils analyzed. PMID:18524325

Piñero González, María; Izquierdo Córser, Pedro; Allara Cagnasso, María; García Urdaneta, Aiza

2007-12-01

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Forests, savannas and grasslands: bridging the knowledge gap between ecology and Dynamic Global Vegetation Models  

Directory of Open Access Journals (Sweden)

Full Text Available The forest, savanna, and grassland biomes, and the transitions between them, are expected to undergo major changes in the future, due to global climate change. Dynamic Global Vegetation Models (DGVMs are very useful to understand vegetation dynamics under present climate, and to predict its changes under future conditions. However, several DGVMs display high uncertainty in predicting vegetation in tropical areas. Here we perform a comparative analysis of three different DGVMs (JSBACH, LPJ-GUESS-SPITFIRE and aDGVM with regard to their representation of the ecological mechanisms and feedbacks that determine the forest, savanna and grassland biomes, in an attempt to bridge the knowledge gap between ecology and global modelling. Model outcomes, obtained including different mechanisms, are compared to observed tree cover along a mean annual precipitation gradient in Africa. Through these comparisons, and by drawing on the large number of recent studies that have delivered new insights into the ecology of tropical ecosystems in general, and of savannas in particular, we identify two main mechanisms that need an improved representation in the DGVMs. The first mechanism includes water limitation to tree growth, and tree-grass competition for water, which are key factors in determining savanna presence in arid and semi-arid areas. The second is a grass-fire feedback, which maintains both forest and savanna occurrences in mesic areas. Grasses constitute the majority of the fuel load, and at the same time benefit from the openness of the landscape after fires, since they recover faster than trees. Additionally, these two mechanisms are better represented when the models also include tree life stages (adults and seedlings, and distinguish between fire-prone and shade-tolerant savanna trees, and fire-resistant and shade-intolerant forest trees. Including these basic elements could improve the predictive ability of the DGVMs, not only under current climate conditions but also and especially under future scenarios.

M. Baudena

2014-06-01

31

Forests, savannas and grasslands: bridging the knowledge gap between ecology and Dynamic Global Vegetation Models  

Science.gov (United States)

The forest, savanna, and grassland biomes, and the transitions between them, are expected to undergo major changes in the future, due to global climate change. Dynamic Global Vegetation Models (DGVMs) are very useful to understand vegetation dynamics under present climate, and to predict its changes under future conditions. However, several DGVMs display high uncertainty in predicting vegetation in tropical areas. Here we perform a comparative analysis of three different DGVMs (JSBACH, LPJ-GUESS-SPITFIRE and aDGVM) with regard to their representation of the ecological mechanisms and feedbacks that determine the forest, savanna and grassland biomes, in an attempt to bridge the knowledge gap between ecology and global modelling. Model outcomes, obtained including different mechanisms, are compared to observed tree cover along a mean annual precipitation gradient in Africa. Through these comparisons, and by drawing on the large number of recent studies that have delivered new insights into the ecology of tropical ecosystems in general, and of savannas in particular, we identify two main mechanisms that need an improved representation in the DGVMs. The first mechanism includes water limitation to tree growth, and tree-grass competition for water, which are key factors in determining savanna presence in arid and semi-arid areas. The second is a grass-fire feedback, which maintains both forest and savanna occurrences in mesic areas. Grasses constitute the majority of the fuel load, and at the same time benefit from the openness of the landscape after fires, since they recover faster than trees. Additionally, these two mechanisms are better represented when the models also include tree life stages (adults and seedlings), and distinguish between fire-prone and shade-tolerant savanna trees, and fire-resistant and shade-intolerant forest trees. Including these basic elements could improve the predictive ability of the DGVMs, not only under current climate conditions but also and especially under future scenarios.

Baudena, M.; Dekker, S. C.; van Bodegom, P. M.; Cuesta, B.; Higgins, S. I.; Lehsten, V.; Reick, C. H.; Rietkerk, M.; Scheiter, S.; Yin, Z.; Zavala, M. A.; Brovkin, V.

2014-06-01

32

Impact of time delays on stochastic resonance in an ecological system describing vegetation  

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In this paper, we investigate the stochastic resonance phenomenon in a vegetation ecological system with time delay, at which the vegetation dynamics is assumed to be disturbed by both intrinsic and extrinsic noises. The signal-to-noise ratio is calculated when a weak periodic signal is added to the system. The impacts of time delay ? and correlation strength k between two noises on the signal-to-noise ratio are discussed, respectively. Our research results show that: (i) the increase of ? or k can enhance the stochastic resonance in the signal-to-noise ratio as a function of intrinsic noise strength ?; (ii) on the contrary, the increase of ? or k can weaken the stochastic resonance in the signal-to-noise ratio as a function of extrinsic noise strength D; and (iii) the increase of ? can lead to double stochastic resonance phenomenon in the signal-to-noise ratio as a function of k.

Han, Qinglin; Yang, Tao; Zeng, Chunhua; Wang, Hua; Liu, Zhiqiang; Fu, Yunchang; Zhang, Chun; Tian, Dong

2014-08-01

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Phenolic content of vegetation in two African rain forests: ecological implications  

Energy Technology Data Exchange (ETDEWEB)

Mature leaves of abundant trees in rain-forest vegetation on acid whitesand soils of the Douala-Edea reserve, Cameroon, contain approximately twice the concentration of phenolic compounds found in similar rain-forest vegetation on lateritic soils of the Kibale forest, Uganda. Phenolics are the most widespread class of ecologically important plant secondary compounds. This study provides support for the hypothesis that vegetation on low-nutrient soils contain relatively high concentrations of chemicals deterrent to herbivores and pathogens. Unlike the two species of Colobus monkeys found in Kibale forest, black Colobus monkeys (Colobus satanas) in the Douala-Edea reserve avoid the leaves of almost all abundant tree species in the area, selectively feeding on leaves of almost all relatively rare components of the vegetation (deciduous trees and second-growth vines). Unlike any other colobine studied to date, black Colobus in the Douala-Edea researve feed heavily on seeds, which contain lower concentrations of phenolic compounds than do leaves in this site.

McKey, D.; Waterman, P.G.; Gartlan, J.S.; Struhsaker, T.T.

1978-01-01

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Vegetation relevés and soil measurements in the Netherlands: the Ecological Conditions Database (EC)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Since its establishment around 1990, the Ecological Conditions Database (EC; GIVD ID EU-00-006) has been accumulating vegetation relevés from the Netherlands, each accompanied by at least one abiotic soil measurement (e.g. pH or nutrient availability). On 1-1-2010, the database contained 8,229 relevés, covering the period from 1936 to 2009, and representing contributions from 110 authors. The most frequently measured soil parameter is pH, with well over 5,000 entries. All the data in the da...

Wamelink, G. W. W.; Adrichem, M. H. C.; Dobben, H. F.; Frissel, J. Y.; Held, M. E.; Joosten, V.; Malinowska, A. H.; Slim, P. A.; Wegman, R. M. A.

2012-01-01

35

Ecological trap for Cnemidophorus ocellifer Spix 1825 (Squamata: Teiidae during removal of vegetation  

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Full Text Available Animals must anticipate future conditions according to current environmental clues. When habitats are rapidly modified, these signs may not reflect the actual environmental quality, leading to a decreased fitness of an individual and its population. During an activity of faunal rescue and scaring away in the coast of Rio Grande do Norte, Brazil, evidence of an ecological trap for the lizard Cnemidophorus ocellifer was observed. We suggest some actions which can minimize the impact of vegetation removal activities on lizards, such as: i better planning before proceeding with deforestation; and ii capture and release of lizards in appropriate locations.

Lucas Bezerra de Mattos Brito

2012-11-01

36

Seed bank dynamics of selected vegetation types in Maputaland, South Africa  

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The seed bank dynamics of five selected vegetation types within the Tembe Elephant Park, Maputaland, northern KwaZulu-Natal, South Africa, were investigated. The different vegetation types from which soil samples were randomly collected during the entire year of 2001 are (a) the very rare and unique Licuati forest and (b) Licuati thicket vegetation, (c) a bare or sparsely vegetated zone surrounding the forest edges, the forest/grassland ecotone, dominated by cats tail grass (...

Kellerman, Millicent Johanna Susanna

2004-01-01

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Revising ecological assumptions about Human papillomavirus interactions and type replacement.  

Science.gov (United States)

The controversy over whether vaccine-targeted HPV types will be replaced by other oncogenic, non-vaccine-targeted types remains unresolved. This is in part because little is known about the ecology of HPV types. Patient data has been interpreted to suggest independence or facilitative interactions between types and therefore replacement is believed to be unlikely. With a novel mathematical model, we investigated which HPV type interactions and their immune responses gave qualitatively similar patterns frequently observed in patients. To assess the possibility of type replacement, vaccination was added to see if non-vaccine-targeted types increased their 'niche'. Our model predicts that independence and facilitation are not necessary for the coexistence of types inside hosts, especially given the patchy nature of HPV infection. In fact, independence and facilitation inadequately represented co-infected patients. We found that some form of competition is likely in natural co-infections. Hence, non-vaccine-targeted types that are not cross-reactive with the vaccine could spread to more patches and can increase their viral load in vaccinated hosts. The degree to which this happens will depend on replication and patch colonization rates. Our results suggest that independence between types could be a fallacy, and so without conclusively untangling HPV within-host ecology, type replacement remains theoretically viable. More ecological thinking is needed in future studies. PMID:24412334

Murall, Carmen Lía; McCann, Kevin S; Bauch, Chris T

2014-06-01

38

Plant physiological ecology and the global changes / Ecofisiologia vegetal e as mudanças globais  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese As mudanças globais englobam importantes alterações nos padrões normais de processos bioquímicos e biofísicos da Terra. Os reais efeitos e retroalimentações das mudanças globais sobre a vegetação ainda são incertos. Parte das incertezas pode ser atribuída à falta de atenção de cientistas e políticos [...] para a vegetação, enquanto componente do sistema terrestre. Entretanto, algumas questões sobre as mudanças globais poderiam ser mais bem esclarecidas por abordagens mais voltadas à ecofisiologia vegetal. Nesse artigo, alguns pontos relacionados e esses problemas, como as limitações em se abordar a vegetação como um componente estático da atmosfera enquanto outros subsistemas do sistema terrestre são dinâmicos, são discutidos. Dentro dessa perspectiva, essa revisão traz uma reflexão inicial do papel da vegetação, em termos de estrutura e funcionamento, no contexto das mudanças globais. Para isso, foi feita uma revisão das terminologias relacionadas às mudanças globais e ao sistema terrestre, buscou-se ilustrar alguns dos principais temas de pesquisa da ecofisiologia vegetal no contexto das mudanças globais. Foram feitas considerações em relação ao tratamento de plantas como sistemas complexos, o que é importante para o estudo de aspectos relacionados à sensibilidade, estabilidade e vulnerabilidade a variações ambientais. Finalmente, são discutidas alternativas que podem ser utilizadas para incorporar aspectos do funcionamento da vegetação, de forma dinâmica, em estudos de mudanças globais, considerando o desafio de mudança de escalas. Espera-se que essa revisão possa auxiliar pesquisadores subsidiando suas estratégias de identificação e compreensão dos efeitos potenciais das mudanças globais sobre os processos mais vulneráveis da vegetação, da folha ao globo. Abstract in english The global changes are marked by alteration on the normal patterns of important biochemical and biophysical processes of the Earth. However, the real effects as well as the feedbacks of the global changes over vegetation are still unclear. Part of this uncertainty can be attributed to the inattentio [...] n of stakeholders and scientists towards vegetation and its complex interrelations with the environment, which drive plant physiological processes in different space-time scales. Notwithstanding, some key subjects of the global changes could be better elucidated with a more plant physiological ecology approach. We discuss some issues related to this topic, going through some limitations of approaching vegetation as a static component of the biosphere as the other sub-systems of the Earth-system change. With this perspective, this review is an initial reflection towards the assessment of the role and place of vegetation structure and function in the global changes context. We reviewed the Earth-system and global changes terminology; attempted to illustrate key plant physiological ecology researches themes in the global changes context; consider approaching plants as complex systems in order to adequately quantify systems characteristics as sensibility, homeostasis, and vulnerability. Moreover, we propose insights that would allow vegetation studies and scaling procedures in the context of the Earth-system. We hope this review will assist researchers on their strategy to identify, understand and anticipate the potential effects of global changes over the most vulnerable vegetation processes from the leaf to the global levels.

João Paulo Rodrigues Alves Delfino, Barbosa; Serge, Rambal; Angela Maria, Soares; Florent, Mouillot; Joana Messias Pereira, Nogueira; Giordane Augusto, Martins.

2012-06-01

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Community Structure of Skipper Butterflies (Lepidoptera, Hesperiidae) along Elevational Gradients in Brazilian Atlantic Forest Reflects Vegetation Type Rather than Altitude  

Science.gov (United States)

Species turnover across elevational gradients has matured into an important paradigm of community ecology. Here, we tested whether ecological and phylogenetic structure of skipper butterfly assemblages is more strongly structured according to altitude or vegetation type along three elevation gradients of moderate extent in Serra do Mar, Southern Brazil. Skippers were surveyed along three different mountain transects, and data on altitude and vegetation type of every collection site were recorded. NMDS ordination plots were used to assess community turnover and the influence of phylogenetic distance between species on apparent community patterns. Ordinations based on ecological similarity (Bray-Curtis index) were compared to those based on phylogenetic distance measures (MPD and MNTD) derived from a supertree. In the absence of a well-resolved phylogeny, various branch length transformation methods were applied together with four different null models, aiming to assess if results were confounded by low-resolution trees. Species composition as well as phylogenetic community structure of skipper butterflies were more prominently related to vegetation type instead of altitude per se. Phylogenetic distances reflected spatial community patterns less clearly than species composition, but revealed a more distinct fauna of monocot feeders associated with grassland habitats, implying that historical factors have played a fundamental role in shaping species composition across elevation gradients. Phylogenetic structure of community turned out to be a relevant additional tool which was even superior to identify faunal contrasts between forest and grassland habitats related to deep evolutionary splits. Since endemic skippers tend to occur in grassland habitats in the Serra do Mar, inclusion of phylogenetic diversity may also be important for conservation decisions. PMID:25272004

Carneiro, Eduardo; Mielke, Olaf Hermann Hendrik; Casagrande, Mirna Martins; Fiedler, Konrad

2014-01-01

40

Categorizing Grassland Vegetation with Full-Waveform Airborne Laser Scanning: A Feasibility Study for Detecting Natura 2000 Habitat Types  

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Full Text Available There is increasing demand for reliable, high-resolution vegetation maps covering large areas. Airborne laser scanning data is available for large areas with high resolution and supports automatic processing, therefore, it is well suited for habitat mapping. Lowland hay meadows are widespread habitat types in European grasslands, and also have one of the highest species richness. The objective of this study was to test the applicability of airborne laser scanning for vegetation mapping of different grasslands, including the Natura 2000 habitat type lowland hay meadows. Full waveform leaf-on and leaf-off point clouds were collected from a Natura 2000 site in Sopron, Hungary, covering several grasslands. The LIDAR data were processed to a set of rasters representing point attributes including reflectance, echo width, vegetation height, canopy openness, and surface roughness measures, and these were fused to a multi-band pseudo-image. Random forest machine learning was used for classifying this dataset. Habitat type, dominant plant species and other features of interest were noted in a set of 140 field plots. Two sets of categories were used: five classes focusing on meadow identification and the location of lowland hay meadows, and 10 classes, including eight different grassland vegetation categories. For five classes, an overall accuracy of 75% was reached, for 10 classes, this was 68%. The method delivers unprecedented fine resolution vegetation maps for management and ecological research. We conclude that high-resolution full-waveform LIDAR data can be used to detect grassland vegetation classes relevant for Natura 2000.

András Zlinszky

2014-08-01

 
 
 
 
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Sexual differences in microhabitat selection of breeding little bustards Tetrax tetrax: Ecological segregation based on vegetation structure  

Science.gov (United States)

We examined sexual differences in patterns of vegetation structure selection in the sexually dimorphic little bustard. Differences in vegetation structure between male, female and non-used locations during reproduction were examined and used to build a presence/absence model for each sex. Ten variables were measured in each location, extracting two PCA factors (PC1: a visibility-shelter gradient; PC2: a gradient in food availability) used as response variables in GLM explanatory models. Both factors significantly differed between female, male and control locations. Neither study site nor phenology was significant. Logistic regression was used to model male and female presence/absence. Female presence was positively associated to cover of ground by vegetation litter, as well as overall vegetation cover, and negatively to vegetation density over 30 cm above ground. Male presence was positively related to litter cover and short vegetation and negatively to vegetation density over 30 cm above ground. Models showed good global performance and robustness. Female microhabitat selection and distribution seems to be related to the balance between shelter and visibility for surveillance. Male microhabitat selection would be related mainly to the need of conspicuousness for courtship. Accessibility to food resources seems to be equally important for both sexes. Differences suggest ecological sexual segregation resulting from different ecological constraints. These are the first detailed results on vegetation structure selection in both male and female little bustards, and are useful in designing management measures addressing vegetation structure irrespective of landscape composition. Similar microhabitat approaches can be applied to manage the habitat of many declining farmland birds.

Morales, M. B.; Traba, J.; Carriles, E.; Delgado, M. P.; de la Morena, E. L. García

2008-11-01

42

The influence of organic-mineral complexes on micro-elements dynamic in ecological systems of vegetables cultivation  

Science.gov (United States)

In ecological systems of vegetable cultivation (hortic antrosols; soils from greenhouses), exists an ensemble of equilibriums between organic-mineral combinations, very sensitive even to relatively small variations of physical-chemical conditions in soils. As such, these can manifest a strong influence on organic matter, clay minerals and microelements from soil, which in turn impacts on the productivity of these soils and the quality of obtained products (vegetables, fruit). Although many studies consider these organic-mineral combinations are meta-stable combinations, our work has shown that the stability of organic-mineral combinations in hortic antrosols (especially for clay-humic, clay-ironhumic combinations and chelates) is higher. We believe that this is due to the higher flexibility of these combinations' structures with the variation of chemical-mineralogical composition and physical-chemical conditions in soil. This paper highlights the results of our research on the differentiation possibility of organic-mineral complexes, depending on their structure and composition (using Raman and FT-IR spectrometry) and the influences manifested by the organic-mineral complexes on the micro-elements dynamic from ecological systems of fresh vegetable cultivation. The non-destructive separation of organic-mineral compounds from soil samples was carried out through iso-dynamic magnetic separation and extraction in aqueous two-phase systems (PEG-based). The Raman and FT-IR spectrometry analyses on raw soil samples, extracts obtained from soil samples and separated mineral fractions have been supplemented by the results obtained through chemical, microscopic and thermal analyses and by UV-VIS absorption spectrometry. Ours experimental studies have been done on representative samples of hortic antrosol from Copou glasshouse (Iasi, Romania), and was studied five micro-elements: Zn, Ni, Cu, Mn, Cr and P. The total contents of the five microelements and their fractions differential bonded on mineral and organic components of hortic antrosols, have been determined by atomic absorption spectrometry after combined sequential extraction in solid phase extraction - aqueous biphasic (PEG based) systems. The specific mechanisms of the microelements interaction with organic components have been estimated on the basis of studies realized on fractions obtained after each extraction step by Raman and FTIR spectrometry. These data have been correlated with those obtained by chemical analysis and UV-VIS spectrometry. In conditions of hortic antrosol, from total contents of Zn, Ni, Cu, Mn and Cr, more than 65 % are binding on organic components. A specific phenomenon of hortic antrosols is the microelements complexation exclusively with the functional groups of organic macromolecules. This phenomenon has two important consequences: (i) the strong fixation of microelements (these can be extracted only in very extremely conditions, which implied the organic part destroying) and (ii) their presence determined major modifications in the structure, conformation and stability of organic macromolecules. Under these conditions, the type and structure of organic-mineral compounds represent determinant factors for the dynamic of micro-elements and organic compounds in ecological systems of vegetables cultivation. Acknowledgments The authors would like to acknowledge the financial support from Romanian Ministry of Education and Research (Project PNCDI 2-D5 no. 51045/07 an Project PNCDI 2-D5 no. 52141 / 08).

Bulgariu, D.; Buzgar, N.; Bulgariu, L.; Rusu, C.; Munteanu, N.

2009-04-01

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Effect of eating vegetables before carbohydrates on glucose excursions in patients with type 2 diabetes  

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The aim of this review was to evaluate whether eating vegetables before carbohydrates could reduce the postprandial glucose, insulin, and improve long-term glycemic control in Japanese patients with type 2 diabetes. We studied the effect of eating vegetables before carbohydrates on postprandial plasma glucose, insulin, and glycemic control for 2.5 y in patients with type 2 diabetes. The postprandial glucose and insulin levels decreased significantly when the patients ate vegetables before car...

Imai, Saeko; Fukui, Michiaki; Kajiyama, Shizuo

2013-01-01

44

Configuration of water resources for a typical river basin in an arid region of China based on the ecological water requirements (EWRs) of desert riparian vegetation  

Science.gov (United States)

Desert riparian vegetation is a natural cover promoting the stability and development of inland river ecosystems in arid regions. Calculating the ecological water requirements (EWRs) of desert riparian vegetation is an important step in achieving reasonable water utilization. Therefore, this study examined the Tarim River, located in an extremely arid region of China, and collected relevant data on hydrology, weather and vegetation using remote sensing. Subsequently, we analyzed the spatial distribution of the desert riparian vegetation in four sections of the Tarim River and calculated the EWR of the desert riparian vegetation using the phreatic evaporation model; additionally, we determined the required runoffs at five hydrologic stations based on the water balance principle. Ultimately, the necessary protection ranges and goals for desert riparian vegetation were established according to the water resource variations in the Tarim River. Our research showed that the total area of desert riparian vegetation along the Tarim River is 16,285.3 km2; this distribution area gradually decreased as the distance from the river increased, and areas varied in the different river sections. The EWRs of desert riparian vegetation from Sections 1 to 5 are 5.698 × 108, 7.585 × 108, 4.900 × 108, 4.101 × 108 m3 and 1.078 × 108 m3, respectively. Therefore, the total EWR of the study region is 23.362 × 108 m3. In terms of the transpiration law of the "unimodal type", the peak value of EWR of natural vegetation occurs in July, and the decreasing trend appears in the other months. Based on the water balance principle, the required runoffs in Alar, Xinquman, Yingbaza, Wusiman and Qiala were determined to be 47.105 × 108, 35.174 × 108, 22.734 × 108, 15.775 × 108 and 7.707 × 108 m3, respectively. According to the water resource frequency and the EWR of the desert riparian vegetation along the Tarim River, we divided the region into three protection ranges: key protection (8.9-11.8 km from the river), basic protection (15.8-21.8 km from the river) and influence protection (43.0 km from the river). This research not only provides a reasonable calculation method for EWR on the scale of a river basin but also supports the healthy development of the desert riparian vegetation ecosystem and helps to achieve the optimal water allocation for this river.

Ling, Hongbo; Guo, Bin; Xu, Hailiang; Fu, Jinyi

2014-11-01

45

A review of fire effects on vegetation and soils in the Great Basin region: response and ecological site characteristics  

Science.gov (United States)

This review synthesizes the state of knowledge on fire effects on vegetation and soils in semi-arid ecosystems in the Great Basin Region, including the central and northern Great Basin and Range, Columbia River Basin, and the Snake River Plain. We summarize available literature related to: (1) the effects of environmental gradients, ecological site, and vegetation characteristics on resilience to disturbance and resistance to invasive species; (2) the effects of fire on individual plant species and communities, biological soil crusts, seed banks, soil nutrients, and hydrology; and (3) the role of fire severity, fire versus fire surrogate treatments, and post-fire grazing in determining ecosystem response. From this, we identify knowledge gaps and present a framework for predicting plant successional trajectories following wild and prescribed fires and fire surrogate treatments. Possibly the three most important ecological site characteristics that influence a site’s resilience (ability of the ecological site to recover from disturbance) and resistance to invasive species are soil temperature/moisture regimes and the composition and structure of vegetation on the ecological site just prior to the disturbance event.

Miller, Richard F.; Chambers, Jeanne C.; Pyke, David A.; Pierson, Fred B.; Williams, C. Jason

2013-01-01

46

Vegetation Dynamics Depending on Ecological Particularities of Bozanta Mare (Maramures County-Romania Tailing Pound. Case Study  

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Full Text Available The present study follows an ecological demarch of reintegration in the scenary through revegetation of an anthropic ground, consisting in a waste pond formed from the flotation activity of non-ferrous ores. Problem statement: To support the formation of a compact vegetal layer, having an anti-errosion and a restoration role, a preliminary study was required regarding the spontaneous settlement of different vegetal species. We have followed the specific floristic composition and the biodiversity on the waste pond, the manner of association of plant species, and the possible interractions with other species from the biocenosis (microorganisms and fungi. We have also studied the pace at which vegetal species settle, as well as the reciprocal influence, from the point of view of vegetation, with the neighbouring area, since the desideratum is the settlement of a vegetation similar to the natural one. Approach: The aim of the research is to draw a list of the vegetal taxa installed on the pond, as well as to detect some succession stages or some possible vegetal associations. We have established the share of different species in the vegetal layer on the waste pond through an analysis of the ecological preferences, of the geographical origin of plant species, of the cariological and bioform profile. All this was done to compare the possible vegetal associations which settle on such anthropic grounds with the neighbouring vegetation. The approach used was the classical one in fitosociology, recommended by the Central European Fitosociological School adapted to the pedo-climatic conditions in Romania. Results: Over 50 species of plants and fungi spontaniously settled have been listed, and we have followed their association as well as their distribution, compared to the microclimatical conditions of the waste pond. In this way,we have distinguished species with a large potential of revegetating highly polluted with heavy metals waste ponds and sites. Conclusions/Recommendations: Starting from this study, we may establish a formula of sustaining the vegetation and using the interractions among species in order to stimulate the settlement of a dense vegetation which might ensure anti-errosion protection and landscape integration.

Monica Marian

2009-01-01

47

Measurement and modelling of evapotranspiration in three fynbos vegetation types  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english Many studies have investigated the water relations of indigenous plants in the fynbos shrublands of the Cape, South Africa. These have mainly focused on understanding the mechanisms by which individual plant species respond to droughts, the frequency and severity of which is expected to increase due [...] to climate change. However, comparatively little information exists on the dynamics of water use by indigenous plants in the region, and, in particular, how water use varies seasonally and between sites. In this study we determined water use by 3 fynbos vegetation types growing at 4 different sites, namely: (i) lowland Atlantis Sand Plain fynbos growing on deep sandy soils, (ii) Kogelberg Sandstone fynbos growing in a riparian zone on deep alluvial soils, (iii) dryland Kogelberg Sandstone fynbos growing on shallow sandy soils at a montane site, and (iv) alluvial Swartland fynbos growing in clayey soils. Evapotranspiration (ET) was quantified at each site during specific periods using a boundary layer scintillometer and energy balance system. A simple dual source model in which the stand ET was calculated as the algebraic sum of outputs from soil evaporation and transpiration sub-models was used to scale up the ET measurements to annual values. The data showed large differences in ET depending on site characteristics and on plant attributes. Dense stands of riparian Sandstone Fynbos had an annual ET of 1 460 mm which exceeded the reference ET of 1 346 mm. Dryland Sandstone Fynbos used only 551 mm of water per year while the Sand Plain Fynbos' annual ET was 1 031 mm, which was similar to the reference ET of 1 059 mm. We conclude that some indigenous plant species use large volumes of water which should be accounted for in, e.g., groundwater recharge estimates, and calculations of incremental water gains after clearing alien invasive plants, among other applications

S, Dzikiti; NZ, Jovanovic; R, Bugan; S, Israel; DC, Le Maitre.

2014-04-03

48

Vegetation change and emerging research feedback for Korean National Long Term Ecological Research (KNLTER  

Directory of Open Access Journals (Sweden)

Full Text Available Various responses of forest ecosystems to climate change underscore the need to improve our understanding of theenvironmentally-driven changes in forests, most effectively by long-term monitoring protocols. We have explored vegetationdynamics based on changes in community structure, species composition, diversity and demographics in fourKorean National Long Term Ecological Research (KNLTER sites--Mt. Nam, Mt. Jeombong, Mt. Worak, and Mt. Jiri--between 2004 and 2009. Most of the sites and forests studied exhibited increments in total basal area, but this was notobserved in Quercus mongolica forests in Mt. Nam and Mt. Worak. Stem density exhibited various changes. Altitudegradient was the representative factor in differences in species composition. Two patterns of compositional change--convergence and divergence--were detected. The vegetation of Mt. Nam and Q. mongolica community of Mt. Workshowed relatively larger changes in composition. However, in the other sites, few changes were observed. Changes ofspecies richness were not notable except for Mt. Nam, where three species were added in the pine forest, whereas onespecies disappeared in the oak forest. In the oak forests, mortality rate was as follows (in descending order: Mt. Nam(25.5%, Mt. Jeombong (24.3%, Mt. Worak (16.4% and Mt. Jiri (0.8%. In the pine forest, the recruitment rate was as follows(in descending order: Mt. Nam (63.7%, Mt. Worak (12.9%, Mt. Jeombong (7.6% and Mt. Jiri (7.3%. The mortalityrate and change rate of basal area were strongly negatively correlated (r = -0.9, P = 0.002, and the recruitment rate andchange rate of density were positively correlated (r = 0.77, P = 0.026. In the KNLTER sites, larger vegetation changes wereattributed to anthropogenic activities such as salvage logging. Suppression or competition for resources would also affectthese changes. Research suggestions such as monitoring to clarify the causes of species mortality were discussed.

Yong Chan Cho

2011-03-01

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Pollination ecology of Tabebuia aurea (Manso) Benth. & Hook. and T. ochracea (Cham.) Standl. (Bignoniaceae) in Central Brazil cerrado vegetation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The pollination ecology and breeding systems of Tabebuia aurea (Manso) Benth. & Hook., and T. ochracea (Cham.) Standl. were investigated in an area of cerrado vegetation in the Federal District of Brazil. These species occur sympatrically, flower massively and synchronously for a month, during the dry season (July to September). Both have diurnal anthesis, with similar floral structures, a yellow tubular corolla and produce nectar. Fourteen species of bees visited both Tabebuia species, but, ...

BARROS MARILUZA GRANJA

2001-01-01

50

Using Remote Sensing to Quantify Vegetation Change and Ecological Resilience in a Semi-Arid System  

Directory of Open Access Journals (Sweden)

Full Text Available This research extends upon land cover change studies by incorporating methodological approaches, which are compatible with heterogeneous ecosystems, are able to link landscape changes to system processes, such as climate change, and provide potential linkages to concepts of ecological resilience. The study region in southern Africa experienced a significant climatic shift in the 1970s, resulting in drier conditions. The state of these ecosystems and their response to such climatic shock is quantified in terms of vegetation amount and heterogeneity. We monitor these characteristics pre- and post-disturbance using a Landsat image series and examine the utility of continuous characterizations of land cover for measuring ecosystem resilience. Land cover change is evaluated using a mean-variance analysis in concert with a spatial persistence analysis. This investigation indicates that although the impact of the decreased precipitation is evident in the 1980s, recovery occurred by the 1990s and 2000s. We found the continuous methodological approach used holds potential for studying heterogeneous landscapes within a resilience framework.

Xia Cui

2013-04-01

51

Potential effects of large linear pipeline construction on soil and vegetation in ecologically fragile regions.  

Science.gov (United States)

Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant community. During the recovery period, the plant community in the work area of the pipeline is replaced by some species that are rare or uncommon in the resident plant community because of human disturbance, thereby increasing the plant diversity in the work area. In terms of plant succession, the duration of the recovery period has a direct effect on the composition and structure of the plant community. The findings provide a theoretical basis and scientific foundation for improving the environmental impact assessment (EIA) of oil and gas pipeline construction as it pertains to the desert steppe ecosystem, and provide a reference point for recovery and management of the eco-environment during the pipeline construction period. PMID:25112841

Xiao, Jun; Wang, Ya-Feng; Shi, Peng; Yang, Lei; Chen, Li-Ding

2014-11-01

52

The variation of components in the radiation balance over different fynbos vegetation types  

International Nuclear Information System (INIS)

The primary aim of this research is to test whether fynbos vegetation has a high reflection coefficient, and the secondary aim is to consider the vegetation at the sites where the radiation measurements were carried out in order to determine whether similar vegetation structural types have similar radiation regimes. In order to do this six sites were selected in the Cape of Good Hope Nature Reserve. At each site the radiation fluxes were measured for three days during the late summer, giving a total of eighteen days of observation. In addition to the radiation measurements structural data was collected for the vegetation at each site so that comparisons between the radiation fluxes and vegetation could be made. Floristic data was also collected, to typify the vegetation at each site. It has been found that fynbos vegetation, as represented by this study, has an unusually low reflection coefficient which varies from 0,08 -0,13. These values are below those recorded in the literature for other heathland vegetation. On the basis of a numerical classification of the vegetation structural data, it has been found that there is no clear relationship between the vegetation and the various components of the radiation balance

53

Linking variability in soil solution dissolved organic carbon to climate, soil type, and vegetation type  

Science.gov (United States)

transport of carbon plays an important role in linking the carbon cycles of terrestrial and aquatic ecosystems. There is, however, a lack of information on the factors controlling one of the main C sources of this lateral flux, i.e., the concentration of dissolved organic carbon (DOC) in soil solution across large spatial scales and under different soil, vegetation, and climate conditions. We compiled a database on DOC in soil solution down to 80 cm and analyzed it with the aim, first, to quantify the differences in DOC concentrations among terrestrial ecosystems, climate zones, soil, and vegetation types at global scale and second, to identify potential determinants of the site-to-site variability of DOC concentration in soil solution across European broadleaved and coniferous forests. We found that DOC concentrations were 75% lower in mineral than in organic soil, and temperate sites showed higher DOC concentrations than boreal and tropical sites. The majority of the variation (R2 = 0.67-0.99) in DOC concentrations in mineral European forest soils correlates with NH4+, C/N, Al, and Fe as the most important predictors. Overall, our results show that the magnitude (23% lower in broadleaved than in coniferous forests) and the controlling factors of DOC in soil solution differ between forest types, with site productivity being more important in broadleaved forests and water balance in coniferous stands.

Camino-Serrano, Marta; Gielen, Bert; Luyssaert, Sebastiaan; Ciais, Philippe; Vicca, Sara; Guenet, Bertrand; Vos, Bruno De; Cools, Nathalie; Ahrens, Bernhard; Altaf Arain, M.; Borken, Werner; Clarke, Nicholas; Clarkson, Beverley; Cummins, Thomas; Don, Axel; Pannatier, Elisabeth Graf; Laudon, Hjalmar; Moore, Tim; Nieminen, Tiina M.; Nilsson, Mats B.; Peichl, Matthias; Schwendenmann, Luitgard; Siemens, Jan; Janssens, Ivan

2014-05-01

54

VEGETATION MAPPING IN WETLANDS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone) gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of veget...

Pedrotti, F.

2004-01-01

55

VEGETATION MAPPING IN WETLANDS  

Directory of Open Access Journals (Sweden)

Full Text Available The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of vegetation series.

F. PEDROTTI

2004-01-01

56

Vegetation composition and structure of southern coastal plain pine forests: An ecological comparison  

Science.gov (United States)

Longleaf pine (Pinus palustris) ecosystems are characterized by a diverse community of native groundcover species. Critics of plantation forestry claim that loblolly (Pinus taeda) and slash pine (Pinus elliottii) forests are devoid of native groundcover due to associated management practices. As a result of these practices, some believe that ecosystem functions characteristic of longleaf pine are lost under loblolly and slash pine plantation management. Our objective was to quantify and compare vegetation composition and structure of longleaf, loblolly, and slash pine forests of differing ages, management strategies, and land-use histories. Information from this study will further our understanding and lead to inferences about functional differences among pine cover types. Vegetation and environmental data were collected in 49 overstory plots across Southlands Experiment Forest in Bainbridge, GA. Nested plots, i.e. midstory, understory, and herbaceous, were replicated four times within each overstory plot. Over 400 species were identified. Herbaceous species richness was variable for all three pine cover types. Herbaceous richness for longleaf, slash, and loblolly pine averaged 15, 13, and 12 species per m2, respectively. Longleaf pine plots had significantly more (p pine plots. Longleaf and slash pine plots were otherwise similar in species richness and stand structure, both having lower overstory density, midstory density, and midstory cover than loblolly pine plots. Multivariate analyses provided additional perspectives on vegetation patterns. Ordination and classification procedures consistently placed herbaceous plots into two groups which we refer to as longleaf pine benchmark (34 plots) and non-benchmark (15 plots). Benchmark plots typically contained numerous herbaceous species characteristic of relic longleaf pine/wiregrass communities found in the area. Conversely, non-benchmark plots contained fewer species characteristic of relic longleaf pine/wiregrass communities and more ruderal species common to highly disturbed sites. The benchmark group included 12 naturally regenerated longleaf plots and 22 loblolly, slash, and longleaf pine plantation plots encompassing a broad range of silvicultural disturbances. Non-benchmark plots included eight afforested old-field plantation plots and seven cutover plantation plots. Regardless of overstory species, all afforested old fields were low either in native species richness or in abundance. Varying degrees of this groundcover condition were also found in some cutover plantation plots that were classified as non-benchmark. Environmental variables strongly influencing vegetation patterns included agricultural history and fire frequency. Results suggest that land-use history, particularly related to agriculture, has a greater influence on groundcover composition and structure in southern pine forests than more recent forest management activities or pine cover type. Additional research is needed to identify the potential for afforested old fields to recover native herbaceous species. In the interim, high-yield plantation management should initially target old-field sites which already support reduced numbers of groundcover species. Sites which have not been farmed in the past 50-60 years should be considered for longleaf pine restoration and multiple-use objectives, since they have the greatest potential for supporting diverse native vegetation. (C) 2000 Elsevier Science B.V.

Hedman, C.W.; Grace, S.L.; King, S.E.

2000-01-01

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Nitrogen deposition effects on Mediterranean-type ecosystems: An ecological assessment  

Energy Technology Data Exchange (ETDEWEB)

We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. - Highlights: > N deposition impacts are understudied in Mediterranean ecosystems out of California. > Dry N deposition is dominant and N flushes are common after rainless periods. > Water availability and P fertility regulate ecosystem responses to N deposition. > Research is needed to determine critical loads for each region and vegetation type. - Nitrogen deposition threatens the Mediterranean regions of the world.

Ochoa-Hueso, Raul, E-mail: raul.ochoa@ccma.csic.es [Department of Plant Physiology and Ecology, Centro de Ciencias Medioambientales, Consejo Superior de Investigaciones Cientificas, C/Serrano 115 Dpdo., 28006 Madrid (Spain); Allen, Edith B. [Department of Botany and Plant Sciences and Center for Conservation Biology, University of California, Riverside, CA 92521 (United States); Branquinho, Cristina; Cruz, Cristina; Dias, Teresa [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biologia Ambiental, Campo Grande, Bloco C4, 1749-016 Lisboa (Portugal); Fenn, Mark E. [US Department of Agriculture (USDA) Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States); Manrique, Esteban [Department of Plant Physiology and Ecology, Centro de Ciencias Medioambientales, Consejo Superior de Investigaciones Cientificas, C/Serrano 115 Dpdo., 28006 Madrid (Spain); Perez-Corona, M. Esther [Department of Ecology, Faculty of Biology, Universidad Complutense de Madrid, C/Jose Antonio Novais 2, 28040 Madrid (Spain); Sheppard, Lucy J. [Centre of Ecology and Hydrology, Bush Estate, Penicuik EH26 0QB (United Kingdom); Stock, William D. [Centre for Ecosystem Management, School of Natural Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Perth, WA 6027 (Australia)

2011-10-15

58

Nitrogen deposition effects on Mediterranean-type ecosystems: An ecological assessment  

International Nuclear Information System (INIS)

We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. - Highlights: ? N deposition impacts are understudied in Mediterranean ecosystems out of California. ? Dry N deposition is dominant and N flushes are common after rainless periods. ? Water availability and P fertility regulate ecosystem responses to N deposition. ? Research is needed to determine critical loads for each region and vegetation type. - Nitrogen deposition threatens the Mediterranean regions of the world.

59

Ecological economic evaluation of the degraded natural vegetation restoration after water transfer to the lower Tarim River, Xinjiang region of northwestern China  

Science.gov (United States)

The emergency ecological water transfer has been implemented for 12 years since 2000 in the lower Tarim River with the goal of restoring the impaired ecosystem and protected habitat environment. It is necessary to evaluate the ecological economic benefits of the vegetative system in order to measure the success of the rehabilitated ecosystem. Based on a hypothesis that the growth of the natural vegetation has a hysteresis with increased groundwater level, this paper suggests that the ecological economic value of the natural vegetation response to groundwater level elevation theoretically includes two parts: the direct value resulting from the increased aboveground biomass of the natural vegetation and the potential value resulting from the natural vegetative restoration in the future. The ecological economic analysis method is applied to calculate assess the ecological economic benefits of the natural vegetative restoration in Kaogan area. The total investment cost of increased groundwater level after seven years is 867 US Dollars in the 100-metre-wide, 2000-metre-long sample belt. The direct value is 1491 US Dollars and the direct input-output ratio is 1:1.7. While the potential value is 4989 US Dollars and the total input-output ratio is 1:7.5. The results indicate that the ecological economic benefits of natural vegetative response are significant after seven years of groundwater level elevation in the lower Tarim River. It also provides a theoretical reference for quantifying the benefits of the degraded ecosystem restoration. Keywords: The lower reaches of Tarim River; ecological water transfer project; ecological economic value; the potential value

Mao, Ye; Hailiang, Xu

2013-04-01

60

Estimation of vegetation LAI from hyperspectral reflectance data: Effects of soil type and plant architecture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The retrieval of canopy biophysical variables is known to be affected by confounding factors such as plant type and background reflectance. The effects of soil type and plant architecture on the retrieval of vegetation leaf area index (LAI) from hyperspectral data were assessed in this study. In situ measurements of LAI were related to reflectances in the red and near-infrared and also to five widely used spectral vegetation indices (VIs). The study confirmed that the spectral contrast betwee...

Darvishzadeh, R.; Skidmore, A. K.; Atzberger, C.; Wieren, S. E.

2008-01-01

 
 
 
 
61

Major vegetation types, climatological data, and solar radiation calculations for Colorado's Brush Creek valley  

Energy Technology Data Exchange (ETDEWEB)

In this report we present information on the vegetative cover, climate, and solar radiation for the Brush Creek valley. A brief vegetative survey was made on October 3, 1984, to identify the vegetation types in the lowest 8 km of the valley; the reader is cautioned that this included only a small part of the Brush Creek valley. The intent was to identify the principal vegetation types, with no attempt to use available scientific sampling techniques to determine accurate relative frequencies of the vegetation types. Nevertheless, the site survey has allowed us to identify the major species of vegetation, and to make reasonably accurate differentiations of both major vegetation types on valley surfaces (the valley floor, two sidewalls, and ridgetops) and the relative abundance of major vegetation types on each surface.

Whiteman, C.D.; Lambeth, R.; Allwine, K.J.

1987-04-01

62

Preliminar evaluation of performance in topcrosses between vegetable type and grain type soybean  

Directory of Open Access Journals (Sweden)

Full Text Available Studies were conducted to evaluate the performance of topcrosses between food type soybean (with tendency to low physiological quality of the seeds with two adapted grain type, seeking to associate adequate human food characteristics with adaptability. The conclusions were: a The best topcrosses for vegetable type soybean were obtained predominantly with ´FT-2` and for seed yield with ´Doko`; b The evaluated topcrosses presented high sensibility to winter conditions in comparison to summer, consequently the selection process in the winter it must be avoided; c The selection for food type soybean it must be established in adequate values between individual plant yield and one hundred seed weight.A soja hortaliça, com sabor agradável, sementes grandes, destinada ao consumo humano direto, apresenta sementes com baixa qualidade fisiológica e alta sensibilidade ao fotoperíodo, sendo que para corrigir estes problemas foram realizados topocruzamentos entre soja tipo alimento com dois tipo grão adaptados, procurando associar características adequadas para alimento humano com adaptabilidade. As conclusões obtidas para estes topocruzamentos foram: a Os melhores topocruzamentos para tipo hortaliça foram obtidos predominantemente com ´FT-2` e para produtividade de grãos com ´Doko`; b Os topocruzamentos avaliados apresentaram alta sensibilidade as condições de inverno em comparação as de verão, com isto o processo de seleção no inverno deve ser evitado; c A seleção para soja tipo hortaliça deve ser estabelecida em valores adequados entre a produtividade por planta individual e peso de cem sementes, evitando o processo de seleção baseado em somente um caráter.

Gilberto K. Yokomizo

2000-01-01

63

Impacts of ecological water conveyance on groundwater dynamics and vegetation recovery in the lower reaches of the Tarim River in northwest China.  

Science.gov (United States)

The ecological water conveyance project (EWCP) in the lower reaches of the Tarim River provided a valuable opportunity to study hydro-ecological processes of desert riparian vegetation. Ecological effects of the EWCP were assessed at large spatial and temporal scales based on 13 years of monitoring data. This study analyzed the trends in hydrological processes and the ecological effects of the EWCP. The EWCP resulted in increased groundwater storage-expressed as a general rise in the groundwater table-and improved soil moisture conditions. The change of water conditions also directly affected vegetative cover and the phenology of herbs, trees, and shrubs. Vegetative cover of herbs was most closely correlated to groundwater depth at the last year-end (R?=?0.81), and trees and shrubs were most closely correlated to annual average groundwater depth (R?=?0.79 and 0.66, respectively). The Normalized Difference Vegetation Index (NDVI) responded to groundwater depth on a 1-year time lag. Although the EWCP improved the NDVI, the study area is still sparsely vegetated. The main limitation of the EWCP is that it can only preserve the survival of existing vegetation, but it does not effectively promote the reproduction and regeneration of natural vegetation. PMID:25074365

Hao, Xingming; Li, Weihong

2014-11-01

64

Productive vegetation: relationships between net primary productivity, vegetation types and climate change in the Wet Tropics bioregion  

International Nuclear Information System (INIS)

Full text: Full text: There is now ample evidence demonstrating the impacts of climate change on biodiversity and human society (Walther ef a/. 2002). Numerous studies have shown climate change is one of the most significant threats to tropical forests, such as the Wet Tropics Heritage Area, due to their high biodiversity and endemism (Pounds ef al. 1999; Hughes 2000; Parmesan and Yohe 2003). Williams ef al. (2003) suggested that small shifts in net primary productivity (NPP) as a result of climate change could lead to potentially massive follow-on effects for the extremely diverse and vulnerable rainforest flora and fauna. It is therefore crucial to explore the relationships between NPP and local biodiversity, especially to create models for different climate change scenarios. Nevertheless, NPP in the Wet Tropics has yet to be estimated. This is the first study to provide a general NPP estimate for the Wet Tropics bioregion using climate surrogates (Schuur 2003). This technique estimates NPP in an accurate, repeatable, and cost-effective way. NPP values were linked to vegetation types and examined under various climatic and environmental conditions. Results show a significant difference in productivity according to vegetation types and climatic variables, with temperature and rainfall seasonality as the most important determining variables. Additionally, lowland and upland vegetations showed a significant difference in productivity patterns throughout the year. Vegettivity patterns throughout the year. Vegetation types located above 1000 metres in altitude had the lowest values of mean annual productivity due to their high rainfall and low temperatures; vegetation types located below 600 metres showed increased productivity values during the wet season (December-March). Net primary productivity will certainly be impacted by changes in temperature and rainfall, due to climate change. Although an increase in NPP values can be predicted for upland areas, the more widely distributed lowlands will drastically decrease their productivity values. Information regarding the variability of net primary productivity across the Wet Tropics bioregion and its possible modifications due to climate change is crucial for management of future scenarios. The results from this study will help management agencies and conservation groups to plan accordingly

65

Using Dehydrated Vegetables in Some Brown Bread Types  

Directory of Open Access Journals (Sweden)

Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 Expanding the range of bakery products in terms of producing supplemented or dietetic products has been an increasingly important trend in contemporary baking. Bakery products as basic and popular food, could be used in the prevention of nutritive deficiencies of many important nutrients, by supplementing the products with biologically valuable ingredients. Such ingredients are dehydrated vegetables in the form of powder. For establishing the bread quality, a special importance shows it’s chemical composition, because the substances that enter in it’s constitution serve to obtaining the energy necessary to the human body. Beside the chemical composition, the bread quality and alimentary use, respectively, depends a large measure on a series of signs: flavor and taste, external appearance, crumb porosity and texture, breads’ volume. This paper belongs to a more complex study, which aims are obtaining some bread assortments with high nutritional value, and improving their sensorial and rheological features, by adding dehydrated vegetables at different levels 4% potato flakes, 2% dehydrated onion, 0.5% dehydrated garlic and 2% dehydrated leek.

Simona Man

2013-11-01

66

Ecología de la vegetación del desierto chihuahuense / Vegetation ecology of the chihuahuan desert  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish El desierto Chihuahuense (DC), el más grande del Continente Americano, está flanqueado por montañas que impiden el paso de los vientos húmedos: la Sierra Madre Oriental, la Faja Volcánica Trans-mexicana y la Sierra Madre Occidental (en México) y Las Rocallosas (en Estados Unidos); cubre una superfic [...] ie de 507,000 km², desde Nuevo México y Texas en Estados Unidos, hasta porciones de los estados de Chihuahua, Coahuila, Durango, Guanajuato, Hidalgo, Nuevo León, Querétaro, San Luis Potosí, Tamaulipas y Zacatecas, en México. El trabajo en campo consistió en la caracterización cualitativa de los principales tipos de vegetación del DC, con base en su fisonomía y en la recolección de ejemplares vegetales para su posterior identificación. Con los datos de composición y fisonomía se elaboraron perfiles semirrealistas de las principales asociaciones vegetales y de las condiciones fisiográficas y edáficas donde se desarrollaban. Las asociaciones detectadas fueron: matorral micrófilo de Larrea tridentata, matorral rosetófilo de Agave lechuguilla, matorral rosetófilo de Dasylirion spp., pastizal, chaparral, nopalera, mezquital, izotal, vegetación de dunas y vegetación halófita. Abstract in english The Chihuahuan Desert (CD), the largest in the Americas, is flanked by mountains that prevent wet winds from blowing across it; those mountain ranges are the Sierra Madre Oriental, the Trans-Mexican Volcanic Belt and the Sierra Madre Occidental in Mexico, and the Rockies in the United States. The de [...] sert covers an area of 507,000 km2, stretching from New Mexico and Texas in the United States to parts of the states of Chihuahua, Coahuila, Durango, Guanajuato, Hidalgo, Nuevo León, Querétaro, San Luis Potosi, Tamaulipas and Zacatecas in Mexico. Field work consisted of the qualitative characterization of the main vegetation types in the CH, based on their physiognomy and the collection of plant specimens for later identification. With the composition and physiognomy data, semi-realistic profiles were made of the main plant associations and the physiographic and soil conditions where they thrive. The associations detected were: Larrea tridentata microphyll scrub, Agave lechuguilla rosette scrub, Dasylirion spp. rosette scrub, grassland, chaparral, nopalera (a patch of prickly pears), mesquite, yucca, dune vegetation and halophytic vegetation.

Diódoro, Granados-Sánchez; Arturo, Sánchez-González; Ro Linnx, Granados Victorino; Amparo, Borja de la Rosa.

67

The use of high altitude remote sensing in determining existing vegetation and monitoring ecological stress  

Science.gov (United States)

High altitude color and multispectral black and white photography was used to survey existing vegetation and soil conditions on the Empire Ranch where large scale development will soon begin. Utilizing stereo pairs of the high altitude color photography, four vegetation classifications were discernable as a function of topography and foliage characteristics. In contrast to the undeveloped Ranch, the same photography was used to detect environmental changes in the Tucson metropolitan area as a result of rapid urbanization. The most prevalent change related to development is the removal of vegetation in high density areas to allow for housing starts. Erosion then occurs where vegetation has been removed.

Foster, K.; Garcia, A.

1972-01-01

68

Arctic Tundra Vegetation Functional Types Based on Photosynthetic Physiology and Optical Properties  

Science.gov (United States)

Non-vascular plants (lichens and mosses) are significant components of tundra landscapes and may respond to climate change differently from vascular plants affecting ecosystem carbon balance. Remote sensing provides critical tools for monitoring plant cover types, as optical signals provide a way to scale from plot measurements to regional estimates of biophysical properties, for which spatial-temporal patterns may be analyzed. Gas exchange measurements were collected for pure patches of key vegetation functional types (lichens, mosses, and vascular plants) in sedge tundra at Barrow, AK. These functional types were found to have three significantly different values of light use efficiency (LUE) with values of 0.013 plus or minus 0.0002, 0.0018 plus or minus 0.0002, and 0.0012 plus or minus 0.0001 mol C mol (exp -1) absorbed quanta for vascular plants, mosses and lichens, respectively. Discriminant analysis of the spectra reflectance of these patches identified five spectral bands that separated each of these vegetation functional types as well as nongreen material (bare soil, standing water, and dead leaves). These results were tested along a 100 m transect where midsummer spectral reflectance and vegetation coverage were measured at one meter intervals. Along the transect, area-averaged canopy LUE estimated from coverage fractions of the three functional types varied widely, even over short distances. The patch-level statistical discriminant functions applied to in situ hyperspectral reflectance data collected along the transect successfully unmixed cover fractions of the vegetation functional types. The unmixing functions, developed from the transect data, were applied to 30 m spatial resolution Earth Observing-1 Hyperion imaging spectrometer data to examine variability in distribution of the vegetation functional types for an area near Barrow, AK. Spatial variability of LUE was derived from the observed functional type distributions. Across this landscape, a fivefold variation in tundra LUE was observed. LUE calculated from the functional type cover fractions was also correlated to a spectral vegetation index developed to detect vegetation chlorophyll content. The concurrence of these alternate methods suggest that hyperspectral remote sensing can distinguish functionally distinct vegetation types and can be used to develop regional estimates of photosynthetic LUE in tundra landscapes.

Huemmrich, Karl Fred; Gamon, John A.; Tweedie, Craig E.; Campbell, Petya K. Entcheva; Landis, David R.; Middleton, Elizabeth M.

2013-01-01

69

Crop Type Classification Using Vegetation Indices of RapidEye Imagery  

Science.gov (United States)

Cutting-edge remote sensing technology has a significant role for managing the natural resources as well as the any other applications about the earth observation. Crop monitoring is the one of these applications since remote sensing provides us accurate, up-to-date and cost-effective information about the crop types at the different temporal and spatial resolution. In this study, the potential use of three different vegetation indices of RapidEye imagery on crop type classification as well as the effect of each indices on classification accuracy were investigated. The Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), and the Normalized Difference Red Edge Index (NDRE) are the three vegetation indices used in this study since all of these incorporated the near-infrared (NIR) band. RapidEye imagery is highly demanded and preferred for agricultural and forestry applications since it has red-edge and NIR bands. The study area is located in Aegean region of Turkey. Radial Basis Function (RBF) kernel was used here for the Support Vector Machines (SVMs) classification. Original bands of RapidEye imagery were excluded and classification was performed with only three vegetation indices. The contribution of each indices on image classification accuracy was also tested with single band classification. Highest classification accuracy of 87, 46 % was obtained using three vegetation indices. This obtained classification accuracy is higher than the classification accuracy of any dual-combination of these vegetation indices. Results demonstrate that NDRE has the highest contribution on classification accuracy compared to the other vegetation indices and the RapidEye imagery can get satisfactory results of classification accuracy without original bands.

Ustuner, M.; Sanli, F. B.; Abdikan, S.; Esetlili, M. T.; Kurucu, Y.

2014-09-01

70

Evaluation of Mediterranean-type vegetation for weedicide activity  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Important differences were found in the response of wheat and lettuce to the treatments, with wheat being generally unaffected. Conversely, a better agreement was found between the sensitivity of lettuce and P. minor. In three (C. villosa, C. ladanifer, and L. stoechas) out of the five donors bioassayed in both species, the same type of answer was found, with an amplification of the effect when P. minor was used. These results support the use of lettuce as a allelopathin indicator speci...

Dias, L. S.; Pereira, I. P.; Dias, A. S.

1995-01-01

71

SACRIFICING THE ECOLOGICAL RESOLUTION OF VEGETATION MAPS AT THE ALTAR OF THEMATIC ACCURACY: ASSESSED MAP ACCURACIES FOR HIERARCHICAL VEGETATION CLASSIFICATIONS IN THE EASTERN GREAT BASIN OF THE SOUTHWEST REGIONAL GAP ANALYSIS PROJECT (SW REGAP)  

Science.gov (United States)

The Southwest Regional Gap Analysis Project (SW ReGAP) improves upon previous GAP projects conducted in Arizona, Colorado, Nevada, New Mexico, and Utah to provide a consistent, seamless vegetation map for this large and ecologically diverse geographic region. Nevada's compone...

72

Noise- and delay-induced regime shifts in an ecological system of vegetation  

International Nuclear Information System (INIS)

In this paper, the stationary probability distribution (SPD) and mean first passage time (MFPT) in a vegetation model with time delay are investigated, where the vegetation dynamics is assumed to be disturbed by both intrinsic and extrinsic noises. The impacts of the intrinsic noise strength ?, extrinsic noise strength D, time delay ? and cross-correlation strength q between two noises on the SPD and MFPT of the regime shifts between the sustainable vegetation and barren states are discussed, respectively. Our main results are as follows. (i) The increase of ? will cause regime shifts from the barren state to the sustainable vegetation state, while the increase of D or ? will cause regime shifts from the sustainable vegetation state to the barren state. (ii) The MFPT as a function of the noise intensities (i.e., ? and D) exhibits one maximum value in the case of q 0.0), the presence of time delay can also cause the existence of extrinsic noise enhanced stability. (paper)

73

Vegetation Types Alter Soil Respiration and Its Temperature Sensitivity at the Field Scale in an Estuary Wetland  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and...

Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

2014-01-01

74

Regional vegetation die-off in response to global-change-type drought  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Future drought is projected to occur under warmer temperature conditions as climate change progresses, referred to here as global-change-type drought, yet quantitative assessments of the triggers and potential extent of drought-induced vegetation die-off remain pivotal uncertainties in assessing climate-change impacts. Of particular concern is regional-scale mortality of overstory trees, which rapidly alters ecosystem type, associated ecosystem properties, and land surface conditions for deca...

Breshears, David D.; Cobb, Neil S.; Rich, Paul M.; Price, Kevin P.; Allen, Craig D.; Balice, Randy G.; Romme, William H.; Kastens, Jude H.; Floyd, M. Lisa; Belnap, Jayne; Anderson, Jesse J.; Myers, Orrin B.; Meyer, Clifton W.

2005-01-01

75

Natura 2000 Habitats map, forest types and vegetation outline of Val Tovanella Nature Reserve  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The vegetation of Val Tovanella Nature Reserve was surveyed during the LIFE Project LIFE04NAT/IT/000190 to produce a map of Habitats of Community interest (Natura 2000 Habitats). The territory of the reserve is mostly occupied by forests, and a large number of forest types and their respective facies were recorded. Particularly important are Tilio-Acerion ravine forests, and black pine forests, which are Priority Habitat types. The forest cover includes wide silver fir and beech forests, a...

Lasen, Cesare; Scariot, Alberto; Sitzia, Tommaso

2008-01-01

76

Bank vegetation of Rimavica River from the perspective of landscape ecology  

International Nuclear Information System (INIS)

The object of our study was 5.3 km long stretch of the river Rimavica with its adjacent ecosystems. The research results show that most of the observed vegetation fulfill its function well in the country. Only certain sections require more human care, in order to strengthen their positive impact on the flow of water and other components of the ecosystem. (authors)

77

Vegetation change and emerging research feedback for Korean National Long Term Ecological Research (KNLTER)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Various responses of forest ecosystems to climate change underscore the need to improve our understanding of theenvironmentally-driven changes in forests, most effectively by long-term monitoring protocols. We have explored vegetationdynamics based on changes in community structure, species composition, diversity and demographics in fourKorean National Long Term Ecological Research (KNLTER) sites--Mt. Nam, Mt. Jeombong, Mt. Worak, and Mt. Jiri--between 2004 and 2009. Most of the sites and for...

Yong Chan Cho; Chang Seok Lee; Hyun Je Cho; Kyu Song Lee; Pil Sun Park

2011-01-01

78

A two-leaf rectangular hyperbolic model for estimating GPP across vegetation types and climate conditions  

Science.gov (United States)

are mainly three types of gross primary production (GPP), including light use efficiency (LUE) model, rectangular hyperbolic model (RHM), and process-based model (PBM). RHM is not widely used because its parameters, namely, quantum yield (?) and maximum photosynthetic rate (Pm), vary temporally with temperature and spatially with vegetation type under natural conditions. In the study, we present a temperature- and vegetation-type-adapted RHM by linking it to the Baldocchi's model to obtain the relationship between ?-Pm and Vcmax,25-temperature to overcome the shortcomings of traditional RHM. The modified RHM (MRHM) coupled with a two-leaf upscaling strategy makes it possible to accurate and fast estimation of GPP at large scale. Twenty-two CO2 eddy-covariance sites with different vegetation types, including evergreen needleleaf forest, deciduous broadleaf forest, grassland, and evergreen broadleaf forest, are used to evaluate the performance of MRHM for GPP estimation. The comparisons of the simulated GPP using MRHM with measured and Boreal Ecosystem Productivity Simulator-simulated GPP demonstrate that the MRHM can simulate GPP as accurately as PBM and in the meantime with the advantage of simplicity as LUE model. These results show the promising potential of MRHM for accurately simulating GPP with relative high computational efficiency, providing an ideal alternative tool for large-scale and long time series GPP simulations.

Wang, Fumin; Chen, Jing M.; Gonsamo, Alemu; Zhou, Bin; Cao, Feifeng; Yi, Qiuxiang

2014-07-01

79

Effects of neighboring vascular plants on the abundance of bryophytes in different vegetation types  

Science.gov (United States)

Due to the climate change, vegetation of tundra ecosystems is predicted to shift toward shrub and tree dominance, and this change may influence bryophytes. To estimate how changes in growing environment and the dominance of vascular plants influence bryophyte abundance, we compared the relationship of occurrence of bryophytes among other plant types in a five-year experiment of warming (T), fertilization (F) and T + F in two vegetation types, heath and meadow, in a subarctic-alpine ecosystem. We compared individual leaf area among shrub species to confirm that deciduous shrubs might cause severe shading effect. Effects of neighboring functional types on the performance of Hylocomium splendens was also analyzed. Results show that F and T + F treatments significantly influenced bryophyte abundance negatively. Under natural conditions, bryophytes in the heath site were negatively related to the abundance of shrubs and lichens and the relationship between lichens and bryophytes strengthened after the experimental period. After five years of experimental treatments in the meadow, a positive abundance relationship emerged between bryophytes and deciduous shrubs, evergreen shrubs and forbs. This relationship was not found in the heath site. Our study therefore shows that the abundance relationships between bryophytes and plants in two vegetation types within the same area can be different. Deciduous shrubs had larger leaf area than evergreen shrubs but did not show any shading effect on H. splendens.

Jägerbrand, Annika K.; Kudo, Gaku; Alatalo, Juha M.; Molau, Ulf

2012-07-01

80

Effect of vegetative filter strips on herbicide runoff under various types of rainfall.  

Science.gov (United States)

Narrow vegetative filter strips proved to effectively reduce herbicide runoff from cultivated fields mainly due to the ability of vegetation to delay surface runoff, promote infiltration and adsorb herbicides. A field trial was conducted from 2007 to 2009 in north-east Italy in order to evaluate the effectiveness of various types of vegetative filter strips to reduce spring-summer runoff of the herbicides mesotrione, metolachlor and terbuthylazine, widely used in maize, and to evaluate the effect of the rainfall characteristics on the runoff volume and concentration. Results show that without vegetative filter strip the herbicide load that reaches the surface water is about 5-6 g ha(-1)year(-1) for metolachlor and terbuthylazine (i.e. 0.5-0.9% of the applied rate), confirming that runoff from flat fields as in the Po Valley can have a minor effect on the water quality, and that most of the risk is posed by a few, or even just one extreme rainfall event with a return period of about 25-27 years, causing runoff with a maximum concentration of 64-77 ?g L(-1). Mesotrione instead showed rapid soil disappearance and was observed at a concentration of 1.0-3.8 ?g L(-1) only after one extreme (artificial) rainfall. Vegetative filter strips of any type are generally effective and can reduce herbicide runoff by 80-88%. Their effectiveness is steady even under severe rainfall conditions, and this supports their implementation in an environmental regulatory scheme at a catchment or regional scale. PMID:22463948

Otto, Stefan; Cardinali, Alessandra; Marotta, Ester; Paradisi, Cristina; Zanin, Giuseppe

2012-06-01

 
 
 
 
81

A Broad Approach to Abrupt Boundaries: Looking Beyond the Boundary at Soil Attributes within and Across Tropical Vegetation Types  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Most research on boundaries between vegetation types emphasizes the contrasts and similarities between conditions on either side of a boundary, but does not compare boundary to non-boundary vegetation. That is, most previous studies lack suitable controls, and may therefore overlook underlying aspects of landscape variability at a regional scale and underestimate the effects that the vegetation itself has on the soil. We compared 25 soil chemistry variables in rainforest, sclerophyll vegetati...

Warman, Laura; Bradford, Matt G.; Moles, Angela T.

2013-01-01

82

Vegetation type modifies the cycling and aromaticity of DOC and N in small-scale urban stormwater basins  

Science.gov (United States)

Urban land use can cause ecological degradation of surface waters through stormwater inputs of dissolved organic carbon (DOC) and total dissolved nitrogen (TDN). Green infrastructure practices such as small-scale (m2) vegetated stormwater basins (e.g. bioretention basins, rain gardens, bioswales) have been implemented for the past 20 years to reduce stormwater quantity and improve water quality in urban ecosystems. Although the efficacy of these practices rests on an ecological assumption that plant-soil interactions will alter the C and N cycles relative to surrounding urban infrastructure, the impact of vegetation type on the biogeochemistry of urban stormwater basins is not well understood. We hypothesized that the two most prevalent types of vegetation planted in stormwater basins in the Midwestern United States, native prairie and woody shrubs, differ in their cycling and export of C and N due to differences in relative woody and parenchymatic tissue inputs to soil organic matter, root morphology, and root exudation. We tested this hypothesis in an open-air field laboratory consisting of 9 vegetated mesocosms (3 native prairie, 3 woody shrub, 3 bare soil) designed in 2005 according to WI-DNR specifications for residential stormwater basin construction. During precipitation events in July-October 2011, we collected stormwater runoff from an adjacent tin roof (417 m2) and conducted 9 runoff applications that mimicked the rate and intensity of runoff that would be received by a small-scale (5.9 m2) stormwater basin in the urban environment during a 2.54 cm rain event. We instrumented each mesocosm to quantify (1) first flush and peak flow concentration of DOC and TDN during gravitational soil water flux (2) DOC and TDN concentration in soil pore space after gravitational water flux ceased, and (3) SUVA254 as an optical proxy for aromaticity in the first flush and peak flow of gravitational soil water flux. Results show significant differences (p<0.05) in both DOC concentration and SUVA254 at peak flow between the native prairie and bare soil. The DOC concentration at peak flow of native prairie and bare soil were 10.50 ± 1.89 mg DOC L-1 (mean ± SE) and 4.96 ± 1.55 mg DOC L-1, respectively. The SUVA254 values for prairie and bare soil at peak flow were 2.82 ± 0.24 L mg-1 C m-1 and 1.75 ± 0.27 L mg-1 C m-1, respectively. Shrubs had a DOC concentration 8.47 ±1.55 mg DOC L-1 at peak flow with a SUVA254 value of 2.68 ±0.24 L mg-1 C m-1. Additionally, we found significant differences (p<0.05) in TDN concentration at first flush, where the prairie and shrub had lower TDN concentrations than bare soil. TDN values were 2.02 ± 0.39, 1.77 ± 0.39, and 4.28 ± 0.39 mg L-1 for prairie, shrub, and bare soil, respectively. These differences in C and N cycling also translated to significant differences (p<0.05) in the DOC:TDN ratio of soil pore water, where the shrub and prairie had significantly higher DOC:TDN ratios than bare soil. DOC:TDN soil pore water ratios were 8.78 ± 0.87, 9.69 ± 0.87, and 4.49 ± 0.87 for prairie, shrub, and bare soil, respectively. We speculate that observed biogeochemical differences in drainage are due to differences in organic matter composition of root-formed macropores in the native prairie and woody shrubs, which may have been the primary pathway of DOC and TDN contributions during preferential flow processes.

Nocco, M. A.; Dolliver, H.; Balster, N. J.

2012-12-01

83

Effect of non-crop vegetation types on conservation biological control of pests in olive groves  

Directory of Open Access Journals (Sweden)

Full Text Available Conservation biological control (CBC is an environmentally sound potential alternative to the use of chemical insecticides. It involves modifications of the environment to promote natural enemy activity on pests. Despite many CBC studies increasing abundance of natural enemies, there are far fewer demonstrations of reduced pest density and very little work has been conducted in olive crops. In this study we investigated the effects of four forms of non-crop vegetation on the abundance of two important pests: the olive psyllid (Euphyllura olivina and the olive moth (Prays oleae. Areas of herbaceous vegetation and areas of woody vegetation near olive crops, and smaller patches of woody vegetation within olive groves, decreased pest abundance in the crop. Inter-row ground covers that are known to increase the abundance of some predators and parasitoids had no effect on the pests, possibly as a result of lack of synchrony between pests and natural enemies, lack of specificity or intra-guild predation. This study identifies examples of the right types of diversity for use in conservation biological control in olive production systems.

Daniel Paredes

2013-07-01

84

Soil Organic Carbon in Particle Size and Density Fractionations under Four Forest Vegetation-Land Use Types in Subtropical China  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Data on the effect of vegetation and land use type on soil organic carbon (SOC) distribution in particle-size and density fractions in the subtropical forest region in China will improve our understanding of the C sequestration potential of those different vegetation-land use types. We quantified SOC in particle size (coarse, medium and fine) and density fractions (light and heavy) under four types of common forest vegetation-land uses: an evergreen broad-leaf forest, a pine forest, a manage...

Suyun Shang; Peikun Jiang; Chang, Scott X.; Zhaoliang Song; Juan Liu; Lei Sun

2014-01-01

85

[Correspondence analysis between occurrence type of Dendrolimus punctatus and topographical and vegetative features].  

Science.gov (United States)

The relationship between the occurrence type of Dendrolimus punctatus and the geographical and vegetative features in subcompartments was analyzed using correspondence analysis and shown by a figure of cluster. The results showed that the majority subcompartments in which D. punctatus occurred frequently were at low elevation and low slope, and distributed among low hills or middle hills, while the subcompartments at high elevation or high slopes, or in low mountains or middle mountains were safe-type. The subcompartments with only one dominant species, especially Pinus elliottii, were easily attacked by D. punctatus. The subcompartments in conifer and broadleaf mixed forest had less insect pests than those in conifer mixed forest. PMID:12561192

Huang, Yingzi; Gu, Dexiang; Zhang, Wenqing; Liang, Chengfeng; Lin, Yuhong; Chen, Zhanfang; Li, Nanlin

2002-09-01

86

Ecology and management of whitefly-transmitted viruses of vegetable crops in Florida.  

Science.gov (United States)

A variety of fresh market vegetables, including watermelon and tomato are economically important crops in Florida. Whitefly-transmitted Squash vein yellowing virus (SqVYV) was first identified in squash and watermelon in Florida in 2005 and shown to cause a severe decline of watermelon vines as crops approach harvest. Florida is most economically impacted by SqVYV, although the virus has been detected more recently in Indiana and South Carolina. The origin and evolutionary history of SqVYV, one of the few members of the genus Ipomovirus within the family Potyviridae, are not known. Sequence diversity of SqVYV isolates collected at different times, from different locations and from different plant species is being analyzed for insights into the origin of the virus. More recently, Cucurbit leaf crumple virus (CuLCrV) and Cucurbit yellow stunting disorder virus (CYSDV), also whitefly-transmitted, have been detected in watermelon in Florida. Tomato yellow leaf curl virus (TYLCV) was first detected in south Florida tomato crops in 1997. Several surveys have been conducted in the region to identify alternative hosts for these four viruses. Cucurbit weeds including Balsam-apple (Momordica charantia), creeping cucumber (Melothria pendula) and smellmelon (Cucumis melo var. dudaim) provide reservoirs for SqVYV, CuLCrV and/or CYSDV. Green bean (Phaseolus vulgaris) also can be a reservoir for CuLCrV. No wild hosts of TYLCV have been reported in Florida. The effectiveness of insecticides and silver plastic mulch to manage whiteflies and mitigate TYLCV has been demonstrated and is currently being evaluated for SqVYV, CuLCrV and CYSDV. In addition, potential sources of SqVYV resistance have been identified in greenhouse and field screening of watermelon germplasm. Further studies to refine these sources of resistance are underway. Lastly, a comprehensive map of 33,560 hectares (82,928 acres) of vegetable fields in the three counties comprising the majority of the southwest Florida vegetable production area has been developed to identify 'hot spots' and reservoir crops for viruses and whiteflies, and will be useful in evaluation of management strategies to decrease virus incidence in commercial fields. PMID:21549768

Adkins, Scott; Webster, Craig G; Kousik, Chandrasekar S; Webb, Susan E; Roberts, Pamela D; Stansly, Philip A; Turechek, William W

2011-08-01

87

The influence of distinct types of aquatic vegetation on the flow field  

Science.gov (United States)

The Sustainable management of fluvial systems dealing with flood prevention, erosion protection and restoration of rivers and estuaries requires implementation of soft/green-engineering methods. In-stream aquatic vegetation can be regarded as one of these as it plays an important role for both river ecology (function) and geomorphology (form). The goal of this research is to offer insight gained from pilot experimental studies on the effects of a number of different elements modeling instream, aquatic vegetation on the local flow field. It is hypothesized that elements of the same effective "blockage" area but of distinct characteristics (structure, porosity and flexibility), will affect both the mean and fluctuating levels of the turbulent flow to a different degree. The above hypothesis is investigated through a set of rigorous set of experimental runs which are appropriately designed to assess the variability between the interaction of aquatic elements and flow, both quantitatively and qualitatively. In this investigation three elements are employed to model aquatic vegetation, namely a rigid cylinder, a porous but rigid structure and a flexible live plant (Cupressus Macrocarpa). Firstly, the flow field downstream each of the mentioned elements was measured under steady uniform flow conditions employing acoustic Doppler velocimetry. Three-dimensional flow velocities downstream the vegetation element are acquired along a measurement grid extending about five-fold the element's diameter. These measurements are analyzed to develop mean velocity and turbulent intensity profiles for all velocity components. A detailed comparison between the obtained results is demonstrative of the validity of the above hypothesis as each of the employed elements affects in a different manner and degree the flow field. Then a flow visualization technique, during which fluorescent dye is injected upstream of the element and images are captured for further analysis and comparison, was employed to visualize the flow structures shed downstream the aquatic elements. This method allows to further observe qualitatively and visually identify the different characteristics of the eddies advected downstream, conclusively confirming the results of the aforementioned experimental campaign.

Valyrakis, Manousos; Barcroft, Stephen; Yagci, Oral

2014-05-01

88

Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS in the red spectral range  

Directory of Open Access Journals (Sweden)

Full Text Available A new method for the satellite remote sensing of different types of vegetation and ocean colour is presented. In contrast to existing algorithms relying on the strong change of the reflectivity in the red and near infrared spectral region, our method analyses weak narrow-band (few nm reflectance structures (i.e. "fingerprint" structures of vegetation in the red spectral range. It is based on differential optical absorption spectroscopy (DOAS, which is usually applied for the analysis of atmospheric trace gas absorptions. Since the spectra of atmospheric absorption and vegetation reflectance are simultaneously included in the analysis, the effects of atmospheric absorptions are automatically corrected (in contrast to other algorithms. The inclusion of the vegetation spectra also significantly improves the results of the trace gas retrieval. The global maps of the results illustrate the seasonal cycles of different vegetation types. In addition to the vegetation distribution on land, they also show patterns of biological activity in the oceans. Our results indicate that improved sets of vegetation spectra might lead to more accurate and more specific identification of vegetation type in the future.

T. Wagner

2007-01-01

89

Physical activity, fruit and vegetable intake and the built environment: ecological and epidemiological studies among youth  

DEFF Research Database (Denmark)

Since the 1990’s, there has been increasing scientific interest in investigating place effects on dietary and exercise behaviors. The two overall aims of this dissertation are designed to investigate at an area level and at an individual level, how food and physical activity resources are spatially distributed by socioeconomic indicators, and whether these associations can be observed between aspects of the built environment and: a) fruit and vegetable intake, and b) vigorous physical activity in individuals. Specifically, this involves operationalization of geographical measures of exposure within neighborhood environments, with development and validation of data used to describe characteristics of exercise and dietary resources. The concept of deprivation amplification is also investigated, which suggests that individual or household deprivation is further enhanced or comprised by the lack of resources in the neighborhood, and could manifest itself in poor health behaviors. This concept is first studied at the neighborhood level, by examining the socioeconomic patterning of food and exercise resources. Next, at the individual level, I examine the combined effects of socioeconomic status and the built environment, and report on how these associations affect individual dietary and exercise behavior. Data drawn for the individually-based analyses stem from the Danish contribution to the Health Behavior in School-aged Children Study (HBSC), an international, cross-sectional population-based study investigating the health and health behaviors of 11-to-15-year old school children. Outcome measures for these studies were infrequent less than daily intake of fruit and vegetables (Paper II) and frequent vigorous physical activity of one hour or more per day (Paper IV). The individual dataset was appended with a validated and cross-referenced objected database built for these studies and contained location information about supermarkets, fast food outlets, and various exercise-supportive resources (public open space, sports facilities, street connectivity, and total length of cycling and walking paths). The neighborhood-based analyses uses validated and cross-referenced objective data about food and physical activity resources in each of the 400 neighborhoods in Copenhagen and combines them with area-level socioeconomic and demographic data derived from The National Statistics Bank of Denmark. Outcome measures for these studies were also defined as the number of supermarkets and fast food outlets in each neighborhood (Paper I) and high exposure (top 25%) to resources supportive of physical activity. Study findings are expressed as either relative risk (RR) or odds ratios (OR), with 95% confidence intervals (CI). In general, study findings indicate no clear socioeconomic patterning of food or physical activity resources by examining neighborhood units alone. For example, there was no association between areal income and supermarket exposure in Copenhagen, while low income areas were more likely to be exposed to fewer fast food outlets than high-income neighborhoods (RR = 0.66; CI: 0.46-0.97). Areas with a high proportion of residents lacking a high school diploma had greater exposure to physical activity resources such as, public open space (OR = 1.90; CI: 1.15-3.15), cycling and walking paths (OR = 3.46; CI: 1.86-6.42) and one or more sports facilities (OR = 2.05; CI: 1.36-3.10) than the referent. Areas with high proportions of children were less likely to have exposure to connected streets (OR = 0.51; 0.31-0.83) than areas with low proportions of children. Results from individual-level studies generally show that while socioeconomic status remains an important individual predictor for diet and exercise behavior, the exposure to resources in the neighborhood environment may differentially affect children according to social class background. Children from low social class backgrounds attending schools with low exposure to supermarkets had the greatest odds of infrequent vegetable (OR = 1.50; CI: 1.03-2.20) and fruit (OR = 1.43

Svastisalee, Chalida

2011-01-01

90

Soil and vegetation carbon stocks in Brazilian Western Amazonia: relationships and ecological implications for natural landscapes.  

Science.gov (United States)

The relationships between soils attributes, soil carbon stocks and vegetation carbon stocks are poorly know in Amazonia, even at regional scale. In this paper, we used the large and reliable soil database from Western Amazonia obtained from the RADAMBRASIL project and recent estimates of vegetation biomass to investigate some environmental relationships, quantifying C stocks of intact ecosystem in Western Amazonia. The results allowed separating the western Amazonia into 6 sectors, called pedo-zones: Roraima, Rio Negro Basin, Tertiary Plateaux of the Amazon, Javari-Juruá-Purus lowland, Acre Basin and Rondonia uplands. The highest C stock for the whole soil is observed in the Acre and in the Rio Negro sectors. In the former, this is due to the high nutrient status and high clay activity, whereas in the latter, it is attributed to a downward carbon movement attributed to widespread podzolization and arenization, forming spodic horizons. The youthful nature of shallow soils of the Javari-Juruá-Purus lowlands, associated with high Al, results in a high phytomass C/soil C ratio. A similar trend was observed for the shallow soils from the Roraima and Rondonia highlands. A consistent east-west decline in biomass carbon in the Rio Negro Basin sector is associated with increasing rainfall and higher sand amounts. It is related to lesser C protection and greater C loss of sandy soils, subjected to active chemical leaching and widespread podzolization. Also, these soils possess lower cation exchangeable capacity and lower water retention capacity. Zones where deeply weathered Latosols dominate have a overall pattern of high C sequestration, and greater than the shallower soils from the upper Amazon, west of Madeira and Negro rivers. This was attributed to deeper incorporation of carbon in these clayey and highly pedo-bioturbated soils. The results highlight the urgent need for refining soil data at an appropriate scale for C stocks calculations purposes in Amazonia. There is a risk of misinterpreting C stocks in Amazonia when such great pedological variability is not taken into account. PMID:17846909

Schaefer, C E G R; do Amaral, E F; de Mendonça, B A F; Oliveira, H; Lani, J L; Costa, L M; Fernandes Filho, E I

2008-05-01

91

An ecological approach to the assessment of vegetation cover on inactive uranium mill tailings sites  

International Nuclear Information System (INIS)

Vascular plants have been collected from abandoned or inactive uranium mill tailings in three mining areas in Canada. The collection was evaluated to determine some characteristics of vegetation development and to identify the plants which will persist on the sites. A total of 170 species were identified. Many of the species are widely distributed in North America, none has been reported as rare in any of the locations from which they were collected. Species richness was highest on Bancroft sites and lowest on Uranium City sites, though values were variable between sites. Forty-four per cent of the total number of species were found on only a single site. Only seven species occurred on more than half of the tailings sites and in all three mining areas. There was no difference between amended and unamended sites in terms of either species richness or species composition. There was no apparent relationship between species richness and either site size, site age or amendment history. The results of this survey suggest that the uranium mill tailings sites are at an early stage of colonization where the seed input from surrounding areas and the heterogeneity of the sites are factors determining species composition and species richness. The fate of an individual once it has reached the site will be determined by its ability to establish on the sites. A perennial growth habit and the ability to expand clonally are important characteristics of the species on the tailings. Theistics of the species on the tailings. The species on the tailings are commonly found in a variety of habitats. Consistent with the observation that the tailings sites are at a stage of early colonization, we find that the few species widely distributed across sites are all characteristic pioneering species with wide environmental tolerances. These species included Populus tremuloides, P. balsamifera, Scirpus cyperinus, Equisetum arvense, Betula papyrifera, Achillea millefolium and Typha spp. The vegetation on the tailings is likely to be characterized by these species for a long period of time. (author)

92

Browsing preference and ecological carrying capacity of sambar deer (Cervus unicolor brookei) on secondary vegetation in forest plantation.  

Science.gov (United States)

The browsing preference and ecological carrying capacity (ECC) of sambar deer (Cervus unicolor brookei) in acacia plantations for management and conservation of the ecosystem were investigated at Sabal Forest Reserve in Sarawak, Malaysia. The identification of the species browsed by the sambar deer was based on an observation of the plant parts consumed. ECC estimation was based on body weight (BW) and the physiological stages of animals browsed in six fenced 4-ha paddocks. Sambar deer were found foraging on only 29 out of 42 species of secondary vegetation in the acacia plantation. The remaining species are too high for the deer to reach. Planted species, Shorea macrophylla are not palatable to the deer. This augurs well for the integration of sambar deer into shorea plantations. The most frequently exploited plants were Ficus spp. Sambar deer preferred woody species more than non-woody species and they are browser animals. By producing metabolizable energy of 19?000 to 27?000 MJ/ha, the ECC was five head/ha to 5.25 head/ha. Given its contribution to the conservation of wildlife and its capacity to sustain the ecosystem, the sambar deer integrated farming system offers a promising strategy for the future of tropical forestry management. PMID:25163638

Ismail, Dahlan; Jiwan, Dawend

2015-02-01

93

Pollination ecology of Tabebuia aurea (Manso Benth. & Hook. and T. ochracea (Cham. Standl. (Bignoniaceae in Central Brazil cerrado vegetation  

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Full Text Available The pollination ecology and breeding systems of Tabebuia aurea (Manso Benth. & Hook., and T. ochracea (Cham. Standl. were investigated in an area of cerrado vegetation in the Federal District of Brazil. These species occur sympatrically, flower massively and synchronously for a month, during the dry season (July to September. Both have diurnal anthesis, with similar floral structures, a yellow tubular corolla and produce nectar. Fourteen species of bees visited both Tabebuia species, but, only three Centris species and Bombus morio, were considered potential pollinators, because of their high frequency on the flowers and their efficiency in carrying pollen. Tests on the breeding systems of T. aurea and T. ochracea demonstrated that boths species are self-incompatible, with late-acting self-incompatibility. The proportion of fruit set from cross pollination (T. aurea 17.2% and T. ochracea 12.3% in both species was low considering the great number of flowers displayed. This suggests a lack of maternal resources for fruit-set. The great amount of seeds per fruit (about 92 in T. aurea and 285 in T. ochracea may represent an investment of maternal resources allocated on higher quality of fertilized ovules.

BARROS MARILUZA GRANJA

2001-01-01

94

Selection of candidate salad vegetables for controlled ecological life support system  

Science.gov (United States)

Higher plants, as one of the essential biological components of CELSS, can supply food, oxygen and water for human crews during future long-duration space missions and Lunar/Mars habitats. In order to select suitable leaf vegetable varieties for our CELSS Experimental Facility (CEF), five varieties of lettuce (“Nenlvnaiyou”, “Dasusheng”, “Naichoutai”, “Dongfangkaixuan” and “Siji”), two of spinach (“Daye” and “Quanneng”), one of rape (“Jingyou No. 1”) and one of common sowthistle were grown and compared on the basis of edible biomass, and nutrient content. In addition, two series of experiments were conducted to study single leaf photosynthetic rates and transpiration rates at 30 days after planting, one which used various concentrations of CO2 (500, 1000, 1500 and 2000 ?mol mol-1) and another which used various light intensities (100, 300, 500 and 700 ?mol m-2 s-1). Results showed that lettuce cvs. “Nenlvnaiyou”, “Siji” and “Dasusheng” produced higher yields of edible biomass; common sowthisle would be a good source of ?-carotene for the diet. Based on the collective findings, we selected three varieties of lettuce (“Nenlvnaiyou”, “Dasusheng” and “Siji”) and one of common sowthistle as the candidate crops for further research in our CEF. In addition, elevated CO2 concentration increased the rates of photosynthesis and transpiration, and elevated light intensity increased the rate of photosynthesis for these varieties. These results can be useful for determining optimal conditions for controlling CO2 and water fluxes between the crops and the overall CELSS.

Qin, L.; Guo, S.; Ai, W.; Tang, Y.

95

Effects of storage time and temperature on the characteristics of vegetable-type soybean grain minimally processed  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of this study was to evaluate the effects of storage time and temperature on the characteristics of vegetable-type soybean grain (cultivar BRS 267) minimally processed and to define the best conditions for its storage. The evaluation was performed by measurement of vitamin C levels, weight loss and color parameters (L*, a*, and b*). The time of storage of vegetable-type soybean grains minimally processed and storage in Styrofoam trays and wrapped with PVC film, caused a decrease...

Karina Czaikoski; Mercedes Concórdia Carrão-Panizzi; Josemeyre Bonifácio da Silva; Elza Iouko Ida

2012-01-01

96

Evaluation of vegetable production management practices to reduce the ecological risk of pesticides.  

Science.gov (United States)

The ability of agricultural management practices to reduce the ecological risks of pesticides was evaluated. Risk quotients, a mathematical description of the relationship between exposure and toxicity, and hazard ratings, a rank of the potential risk of pesticides to aquatic environments, were calculated for conventional and alternative cultivation practices for tomatoes: Poly-Bare, raised beds covered with polyethylene mulch with bare-soil furrows; Poly-Rye, raised beds covered with polyethylene mulch with cereal rye (Secale cereale) grown in the furrows; and Vetch, raised beds and furrows planted with hairy vetch seed (Vicia villosa). Evaluations were conducted using measured pesticide concentrations in runoff at the edge-of-field and estimated environmental concentrations in an adjacent creek and a theoretical pond receiving the runoff. Runoff from Poly-Bare presented the greatest risk to ecosystem health and to sensitive organisms, whereas the use of Vetch minimized these risks. Previous studies have shown that harvest yields were maintained and that runoff volume, soil loss, and off-site transport of pesticides measured in runoff were reduced using the alternative management practices (Poly-Rye and Vetch). Together, these results indicate that the alternative management practices (Poly-Rye and Vetch) have a less adverse impact on the environment than the conventional management practice (Poly-Bare) while providing growers with an acceptable economic return. In addition, the present study demonstrates the need to consider the management practice when assessing the potential risks and hazards for certain pesticides. PMID:17941735

Rice, Pamela J; Hapeman, Cathleen J; McConnell, Laura L; Sadeghi, Ali M; Teasdale, John R; Coffman, C Benjamin; McCarty, Gregory W; Abdul-Baki, Aref A; Starr, James L

2007-11-01

97

VEGETABLE BUT NOT FRUIT CONSUMPTION REDUCES THE RISK OF TYPE 2 DIABETES IN CHINESE WOMEN1  

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We examined associations between fruit and vegetable intake and the incidence of type 2 diabetes (T2D5) in a population-based prospective study of 64,191 women with no history of T2D or other chronic diseases at study recruitment and with valid dietary information. Dietary intake was assessed by in-person interviews using a validated food frequency questionnaire. During 297,755 person-years of follow-up, 1,608 new cases of T2D were documented. A Cox regression model was employed to evaluate t...

Villegas, Raquel; Shu, Xiao Ou; Gao, Yu-tang; Yang, Gong; Elasy, Tom; Li, Honglan; Zheng, Wei

2008-01-01

98

Evaluation of the shelf-life of vegetable-type soybean pods  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The shelf-life of the vegetable-type soybean pods stored under different conditions was evaluated by chemical characteristics and color. The pods were harvested in the R6 stage and stored either at 30 or 7ºC for 9 d. After the storage period, the pods were blanched and threshed, and the immature green grains were used for the analysis. The protein content decreased after 6 d of storage at 7ºC. There was no difference in the lipid content after the storage at 30 and 7ºC for 9 d. The starch ...

Andréia Cristina Santana; Mercedes Concórdia Carrão-Panizzi; José Marcos Gontijo Mandarino; Rodrigo Santos Leite; Josemeyre Bonifácio da Silva; Elza Iouko Ida

2012-01-01

99

Change of land use classes and vegetation types between 1927 and 2013 south of Linköping  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In 1927, the forest in Östergötland was inventoried for the first time by Riksskogstaxeringen. The original, hand-written field protocols have recently been digitized. This made it possible to repeat the fieldwork in the same transects and using the same methodology. The purpose of this study was to re-inventory an area in Sweden south of Linköping to assess changes in land use classes and vegetation types. Another purpose was to identify practical problems with the re-inventory as well as...

Lo?nander, Johanna

2013-01-01

100

Classification of the vegetation of the A land type in the Mooi River catchment area, Transvaal Plantegroeiklassifikasie van die A-landtipe van die Mooirivier - opvanggebied, Transvaal  

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Full Text Available The aim of this study was to identify, characterize and interpret ecologically, by using habitat characteristics, the major vege­tation units and their variations of the A land type. Five plant communities were successfully distinguished by applying a numerical classification and Braun-Blanquet procedures. The plant communities could easily be correlated with specific habitat types. A clear distinction could be made between plant communities of the upland and lowland areas. Vegetation gradients and associated gradients in habitat were identified by using an ordination technique. The study emphasized the importance of topography and soil type for the delimitation of management units for farming or nature conservation practices.Die doel van hierdie studie was om hoofplantegroei-eenhede en hulle variasies, van die A-landtipe, te identifiseer, karakteriseer en aan die hand van die habitat ekologies te interpreteer. Vyf plantgemeenskappe is deur die toepassing van 'n numeriese klassifikasie en Braun-Blanquet-prosedures geidentifiseer en elk is met ’n spesifieke habitat gekorreleer. 'n Duidelike onderskeid is tussen die hoogliggende en die laagliggende plantgemeenskappe gemaak. Plantegroeigradiënte en geassosieerde gradiënte in habitat is deur toepassing van ’n ordeningstegniek geidentifiseer. Die studie beklemtoon die belangrikheid van topografie en grondtipe vir die afbakening van plantegroei-bestuurseenhede vir boerdery of natuurbewaring.

H. Bezuidenhout

1991-07-01

 
 
 
 
101

Variation in net greenhouse gas balance across high Arctic vegetation types  

Science.gov (United States)

Climate in high-latitude environments is predicted to undergo the most pronounced warming and increase in precipitation. In warmer and wetter soils, the net balance of greenhouse gases (GHGs) such as CO2, CH4 and N2O could be altered, Changes in GHG dynamics, however, may not be uniform across the arctic landscape, where different vegetation types are distributed along moisture gradients. To predict the future contribution of Arctic ecosystems to global climate, it is important to understand the interactions between vegetation type and net GHG balance. Little research, however, has explored spatial variability in net GHG emissions from high-Arctic landscapes, especially in polar barrens that dominate the region. Most studies concentrated either on CO2 fluxes, or were performed in low-Arctic ecosystems and polar oases. In 2008 and 2009, we measured CO2, CH4 and N2O fluxes using static chamber techniques at Cape Bounty, Melville Island, Nunavut, Canada. Measurements were performed using transparent static chambers (to measure NEP, or opaque static chambers (for CH4, N2O and ecosystem respiration) in three major plant community types across a moisture gradient: polar semi-desert (PD), mid-moisture tundra (MM) and wet sedge meadow (WS). CO2 fluxes were measured with a VAISALA infrared gas analyzer, while trace gas fluxes were measured in air samples collected over 40 minutes and stored in pre-evacuated glass vials. In 2008, only the WS community was a net CO2sink, whereas in 2009 all vegetation types were CO2 sources, with MM emitting almost ten-fold more carbon than the other two plant communities. WS released the most N2O and CH4, followed by MM communities, while PD soils were net CH4 sinks. There was little discernible influence of environmental factors on N2O fluxes. Emissions of CH4 and N2O, tended to be higher in the warmer year 2008. On a given land area, depending on the climate of a given season and on the relative cover of the different vegetation types, CH4 flux can result either in carbon efflux or uptake (4.12x10-3 g C m-2 season-1 in 2008 vs. -12.69x10-3 g C m-2 season-1 in 2009 for the entire Cape Bounty area). The CH4 effluxes are small compared to more southern ecosystems, but uptake values are significant, comparable even to tropical ecosystems. Given the vast expanses of polar deserts, and the more potent nature of CH4 as a GHG, changes in the spatial extent of the different vegetation types could have a significant impact on net climate forcing attributed to high-Arctic ecosystems.

Scott, N. A.; Wagner, I.; Neil, A.

2012-12-01

102

Species composition and temporal activity of Arctiinae (Lepidoptera: Erebidae) in two cerrado vegetation types  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Arctiinae moths include nearly 11,000 species worldwide, of which approximately 700 species occur in the Brazilian Cerrado. The aim of this study was to describe the species composition of Arctiinae, as well as the variation in annual and nightly moth activity, in two Cerrado vegetation types. We sa [...] mpled moths one night per month from September 2008 to June 2009, in the gallery forest and in the cerrado sensu stricto in the Jardim Botânico de Brasília. We collected 395 tiger moths belonging to 65 morphospecies; 74% of the species belonged to the tribe Arctiini and 26% to Lithosiini. Thirty-one species (47.7%) occurred only in the gallery forest, 13 (20%) occurred only in the cerrado sensu stricto, and 21 (32.3%) occurred in both vegetation types. Additionally, we found the greatest species richness between 7:00 p.m. and 8:00 p.m., and these hours were associated with 21 and 22 species, respectively. Most species (51.8%) were active for up to three hours during the night. In general, the species composition differed between the dry and rainy seasons, and the similarity of the fauna also varied hourly. Based on our results, we suggest that rapid inventories of Arctiinae be performed in both rainy and dry seasons, and sampling should be carried out the entire night.

Scheila, Scherrer; Viviane G., Ferro; Marina N., Ramos; Ivone R., Diniz.

2013-04-01

103

Categorizing Grassland Vegetation with Full-Waveform Airborne Laser Scanning: A Feasibility Study for Detecting Natura 2000 Habitat Types  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There is increasing demand for reliable, high-resolution vegetation maps covering large areas. Airborne laser scanning data is available for large areas with high resolution and supports automatic processing, therefore, it is well suited for habitat mapping. Lowland hay meadows are widespread habitat types in European grasslands, and also have one of the highest species richness. The objective of this study was to test the applicability of airborne laser scanning for vegetation mapping of dif...

András Zlinszky; Anke Schroiff; Adam Kania; Balázs Deák; Werner Mücke; Ágnes Vári; Balázs Székely; Norbert Pfeifer

2014-01-01

104

Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS) in the red spectral range  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new method for the satellite remote sensing of different types of vegetation and ocean colour is presented. In contrast to existing algorithms relying on the strong change of the reflectivity in the red and near infrared spectral region, our method analyses weak narrow-band (few nm) reflectance structures (i.e. "fingerprint" structures) of vegetation in the red spectral range. It is based on differential optical absorption spectroscopy (DOAS), which is usually applied for the anal...

Wagner, T.; Beirle, S.; Deutschmann, T.; Grzegorski, M.; Platt, U.

2007-01-01

105

Vegetation types alter soil respiration and its temperature sensitivity at the field scale in an estuary wetland.  

Science.gov (United States)

Vegetation type plays an important role in regulating the temporal and spatial variation of soil respiration. Therefore, vegetation patchiness may cause high uncertainties in the estimates of soil respiration for scaling field measurements to ecosystem level. Few studies provide insights regarding the influence of vegetation types on soil respiration and its temperature sensitivity in an estuary wetland. In order to enhance the understanding of this issue, we focused on the growing season and investigated how the soil respiration and its temperature sensitivity are affected by the different vegetation (Phragmites australis, Suaeda salsa and bare soil) in the Yellow River Estuary. During the growing season, there were significant linear relationships between soil respiration rates and shoot and root biomass, respectively. On the diurnal timescale, daytime soil respiration was more dependent on net photosynthesis. A positive correlation between soil respiration and net photosynthesis at the Phragmites australis site was found. There were exponential correlations between soil respiration and soil temperature, and the fitted Q10 values varied among different vegetation types (1.81, 2.15 and 3.43 for Phragmites australis, Suaeda salsa and bare soil sites, respectively). During the growing season, the mean soil respiration was consistently higher at the Phragmites australis site (1.11 µmol CO2 m(-2) s(-1)), followed by the Suaeda salsa site (0.77 µmol CO2 m(-2) s(-1)) and the bare soil site (0.41 µmol CO2 m(-2) s(-1)). The mean monthly soil respiration was positively correlated with shoot and root biomass, total C, and total N among the three vegetation patches. Our results suggest that vegetation patchiness at a field scale might have a large impact on ecosystem-scale soil respiration. Therefore, it is necessary to consider the differences in vegetation types when using models to evaluate soil respiration in an estuary wetland. PMID:24608636

Han, Guangxuan; Xing, Qinghui; Luo, Yiqi; Rafique, Rashad; Yu, Junbao; Mikle, Nate

2014-01-01

106

Prioritydirections of development of jscrosneft: alternative types of fueland ecology.  

Directory of Open Access Journals (Sweden)

Full Text Available In this article possibility of an exit of Rosneft on the market of alternative types of fuel is considered. The attention is paid that, according to a large number of experts, there is a probability of that in the near future environmentally friendly and inexhaustible fuel will come to alternative to habitual motor fuel – hydrogen. In article all possible ways and cost of production of hydrogen, experience of use of hydrogen engines in automotive industry and possibility of the offer and advance in the hydrogen market, as alternative type of fuel, to clients of Rosneft are attentively analyzed.

Irina Pryadko

2013-12-01

107

Survey to determine the adequacy of existing conserved areas in relation to vegetation types. A preliminary report.  

Directory of Open Access Journals (Sweden)

Full Text Available

The report is a broad survey of the conservation status of South African vegetation. Data and maps show the distribution and total areas of conserved lands by the various conservation agencies, the size structure of nature reserves, the areas and percentages of conserved areas in relation to the 70 veld types and seven main vegetation types into which South Africa was divided by Acocks (1953, and important conservation requirements in the Bantu Homelands. Major conservation deficiencies lie in the Karoo and Karroid Bushveld and Grassland Types of vegetation, where 42 veld types have none or virtually no conservation, and in the Tropical Bush and Savanna Types to which-belong nine of the 10 remaining veld types extremely lacking in conservation. Additional reserves are needed' to conserve certain important and local ecosystems and species in the remaining 18 veld types, especially the Sclerophyllous Bush (Macchia or Fynbos and Temperate and Transitional Forest and Scrub Types, and in certain Coastal Tropical Forest and Thornveld Types. Apart from minor deficiencies, the conservation status is outstanding for six of these 18 veld types (up to 47 per cent under conservation, and very good for another six veld types.

D. Edwards

1974-07-01

108

Effects of storage time and temperature on the characteristics of vegetable-type soybean grain minimally processed  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this study was to evaluate the effects of storage time and temperature on the characteristics of vegetable-type soybean grain (cultivar BRS 267 minimally processed and to define the best conditions for its storage. The evaluation was performed by measurement of vitamin C levels, weight loss and color parameters (L*, a*, and b*. The time of storage of vegetable-type soybean grains minimally processed and storage in Styrofoam trays and wrapped with PVC film, caused a decreased in vitamin C levels and color parameters and increased weight loss. This process was intensified with higher temperature at 25 °C than 5°C. To maintain appropriate levels of vitamin C, weight and color of vegetable-type soybean grains minimally processed and storage in trays wrapped in plastic wrap, recommended storage for 3 days at 5°C.

Karina Czaikoski

2012-08-01

109

Effects of storage time and temperature on the characteristics of vegetable-type soybean grain minimally processed  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english The objective of this study was to evaluate the effects of storage time and temperature on the characteristics of vegetable-type soybean grain (cultivar BRS 267) minimally processed and to define the best conditions for its storage. The evaluation was performed by measurement of vitamin C levels, we [...] ight loss and color parameters (L*, a*, and b*). The time of storage of vegetable-type soybean grains minimally processed and storage in Styrofoam trays and wrapped with PVC film, caused a decreased in vitamin C levels and color parameters and increased weight loss. This process was intensified with higher temperature at 25 °C than 5°C. To maintain appropriate levels of vitamin C, weight and color of vegetable-type soybean grains minimally processed and storage in trays wrapped in plastic wrap, recommended storage for 3 days at 5°C.

Karina, Czaikoski; Mercedes Concórdia, Carrão-Panizzi; Josemeyre Bonifácio da, Silva; Elza Iouko, Ida.

2012-08-01

110

Significance of diet type and diet quality for ecological diversity of African ungulates  

Digital Repository Infrastructure Vision for European Research (DRIVER)

1.We test two nutritional hypotheses for the ecological diversity of ungulates, the browser/grazer (diet type) and diet quality models, among free-ranging herbivores in a South African savanna, the Kruger National Park. Tests are based on assessment of relationships between diet type and diet quality with body mass and hypsodonty, two morphological features that have been associated with both elements. 2.We use stable carbon isotope ratios of faeces to reconstruct diet in terms of proporti...

Codron, D.; Lee-thorp, J. A.; Sponheimer, M.; Codron, J.; Ruiter, D. J.; Brink, J. S.

2007-01-01

111

On the potential vegetation feedbacks that enhance phosphorus availability – insights from a process-based model linking geological and ecological timescales  

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We find that active P uptake is an essential mechanism for sustaining P availability on long timescales, whereas biotic de-occlusion might serve as a buffer on timescales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modelling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth, and that vegetation on old soils has a smaller biomass production rate when P becomes limiting. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and ecological timescales under different environmental settings.

C. Buendía

2014-07-01

112

Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.  

Science.gov (United States)

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km(2) in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed. PMID:24699917

Li, XingRong; Zhang, ZhiShan; Tan, HuiJuan; Gao, YanHong; Liu, LiChao; Wang, XingPing

2014-05-01

113

Plant Traits Demonstrate That Temperate and Tropical Giant Eucalypt Forests Are Ecologically Convergent with Rainforest Not Savanna  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ecological theory differentiates rainforest and open vegetation in many regions as functionally divergent alternative stable states with transitional (ecotonal) vegetation between the two forming transient unstable states. This transitional vegetation is of considerable significance, not only as a test case for theories of vegetation dynamics, but also because this type of vegetation is of major economic importance, and is home to a suite of species of conservation significance, including the...

Tng, David Y. P.; Jordan, Greg J.; Bowman, David M. J. S.

2013-01-01

114

Screening for clostridium botulinum type A, B, and E in cooked chilled foods containing vegetables and raw material using polymerase chain reaction and molecular probes.  

Science.gov (United States)

A molecular method was used for the detection of Clostridium botulinum spores of type A, B, and E in commercial cooked and pasteurized vegetable purées and in the raw materials (vegetables and other ingredients). The method allowed the detection of less than 8 spores/g of product for C. botulinum type A, less than 1 spore/g for proteolytic type B, less than 21 spores/g for nonproteolytic type B, and less than 0.1 spore/g for type E. Thirty-seven samples of raw vegetables and ingredients were tested for the presence of C. botulinum type A, B, and E; 88 and 90 samples of vegetable purées were tested, respectively, for the presence of C. botulinum type A and B and for the presence of C. botulinum type E. All samples were negative, suggesting that the prevalence of C. botulinum in these vegetable purées and the raw ingredients is probably low. PMID:11271768

Braconnier, A; Broussolle, V; Perelle, S; Fach, P; Nguyen-The, C; Carlin, F

2001-02-01

115

Environment effects on wood density of vegetation types in Minas Gerais State – Brazil  

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Full Text Available The objective was to verify the general behavior of wood density of native tree species in forest types in Minas Gerais state. The trees scaling data were obtained from the Forest Inventory of Minas Gerais State. Were used data from 1988 trees distributed in different forest formations. From each tree, five discs of wood were removed, at the 0, 25, 50, 75 and 100% of the total height. The wood basic density of each disk was determined according to NBR 7190/1997. The ombrophylous forest, semideciduous forest, savanna woodland, typical savanna and deciduous forest presented average wood density of 0.502, 0.561, 0.585, 0.612 and 0.675 g.cm-3, respectively, all statistically different. It was found a clear and consistent relation between wood density and environment characteristics that affect the different vegetation types in Minas Gerais State. The forest formations present environmental conditions so typical that they affect the floristic composition and also the cambial and physiological activity of plants, causing particular wood densities to forests formations.

Antônio Donizette de Oliveira

2012-06-01

116

Regular, high, and moderate intake of vegetables rich in antioxidants may reduce cataract risk in Central African type 2 diabetics  

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Full Text Available Moise Mvitu,1 Benjamin Longo-Mbenza,2 Dieudonné Tulomba,3 Augustin Nge31Department of Ophthalmology, University of Kinshasa, Democratic Republic of Congo; 2Faculty of Health Sciences, Walter Sisulu University, South Africa; 3Biostatistics Unit, Lomo Medical Center and Heart of Africa Center of Cardiology, Kinshasa, Democratic Republic of CongoBackground: Antioxidant nutrients found in popularly consumed vegetables, including red beans, are thought to prevent diabetic complications. In this study, we assessed the frequency and contributing factors of intake of fruits and vegetables rich in antioxidants, and we determined their impact on the prevention of diabetes-related cataract extraction.Methods: This was a cross-sectional study, run in Congo among 244 people with type 2 diabetes mellitus. An intake of ?three servings of vegetables rich in antioxidants/day, intake of red beans, consumption of fruit, and cataract extraction were considered as dependent variables.Results: No patient reported a fruit intake. Intake of red beans was reported by 64 patients (26.2%, while 77 patients (31.6% reported ?three servings of vegetables rich in antioxidants. High socioeconomic status (OR = 2.3; 95% CI: 1.1–12.5; P = 0.030 and moderate alcohol intake (OR = 4; 95% CI: 1.1–17.4; P = 0.049 were the independent determinants of eating ?three servings of vegetables rich in antioxidants. Red beans intake (OR = 0.282; 95% CI: 0.115–0.687; P > 0.01 and eating ?three servings of vegetables rich in antioxidants (OR = 0.256; 95% CI: 0.097–0.671; P = 0.006 were identified as independent and protective factors against the presence of cataracts (9.8% n = 24, whereas type 2 diabetes mellitus duration ?3 years was the independent risk factor for cataract extraction (OR = 6.3; 95% CI: 2.1–19.2; P > 0.001 in the model with red beans intake and OR = 7.1; 95% CI: 2.3–22.2; P > 0.001 in the model with ?three servings of vegetables rich in antioxidants.Conclusion: Red beans intake and adequate quantity of intake of vegetables rich in antioxidants were found to be associated with reduced risk of cataract in these Congolese with type 2 diabetes mellitus. Education on nutrition and health promotion programs are needed to encourage people to eat vegetables and fruit.Keywords: red beans, cataract extraction, socioeconomic status, public health implications

Mvitu M

2012-06-01

117

Estado ecológico de ríos y vegetación ribereña en el contexto de la nueva Ley General de Aguas de México / Ecological status of rivers and riparian vegetation within the new General Mexican Water's Law context  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Los ríos son unidades vitales en el funcionamiento de las cuencas que, debido al transporte y a la circulación cíclica del agua, permiten la existencia de los seres vivos. Poseen gran valor ecológico y ambiental dada su influencia sobre otros ecosistemas y los beneficios que proporcionan al hombre, [...] tanto para consumo como para riego y uso en los ámbitos agrícola e industrial. Sin embargo, casi todos los ríos de México presentan algún tipo de deterioro. Alrededor de 73 % de los sistemas acuáticos muestran contaminación, lo que empobrece la salud de estos ecosistemas. El objetivo de este trabajo es proponer que en la formulación de la nueva ley general de aguas se considere la regulación de la vegetación ribereña, pues su influencia en el mantenimiento y en la rehabilitación del estado ecológico de los ríos es fundamental. Se sugiere que la nueva ley contenga una sección de protección ambiental en la que se incluya a la vegetación ribereña como elemento clave para proteger, conservar y restaurar los ríos. Asimismo, que la delimitación de dicha vegetación se apegue a las condiciones naturales de inundación del cauce, con una frecuencia de una vez cada ocho años, de acuerdo con la variabilidad del flujo. Además, su manejo debe tomar en cuenta la reforestación y el mantenimiento de especies vegetales nativas de cada región. Abstract in english Rives are vital units in the functioning of the watersheds that, due to the transportation and circulation of water, allow the existence of life. They are of great ecological and environmental value because of their influence on other ecosystems as well as the benefits they give to humankind, not on [...] ly in the consumption for irrigation but also in the use in the agricultural and industrial areas. However, almost all the rivers in Mexico show a certain type of deterioration. About 70 % of the aquatic systems shows contamination which diminishes the health of these ecosystems. The objective of this work is to propose that the riparian vegetation should be included in the making of the new general law of water because its influence on the maintenance and rehabilitation of the ecological state of rivers is fundamental. It has been suggested a new law that contains a section of environmental protection which includes the riparian vegetation as a key element to protect, preserve, and restore rivers. Likewise, the boundaries of this vegetation should be according to the natural conditions of flooding in the bed of the river, with a once-in-every eight years- frequency, according to the variability of flow. In addition, its handling must consider the reforestation and maintenance of native vegetation species in each region.

Mayra, MENDOZA CARIÑO; Abel, QUEVEDO NOLASCO; Ángel, BRAVO VINAJA; Héctor, FLORES MAGDALENO; María de Lourdes, DE LA ISLA DE BAUER; Francisco, GAVI REYES; Bertha Patricia, ZAMORA MORALES.

118

Ecology of Nematodes Under Influence of Cucurbita spp. and Different Fertilizer Types  

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In a field study conducted in Georgia, cucurbit plants with high (Cucurbita andreana) and low (Cucurbita maxima) concentrations of cucurbitacins were used in combination with two types of fertilizers to investigate their effects on the community of soil nematodes. Ecological measures of soil nematode community structure such as total nematode abundance, number of genera, trophic diversity, trophic group proportions, fungivore/bacterivore ratio, and modified maturity index were assessed and co...

Porazinska, D. L.; Coleman, D. C.

1995-01-01

119

Functional analysis and modelling of vegetation: plant functional types in a mesocosmos experiment and a mechanistic model  

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The focus of this thesis lies on the functional analysis and modelling of vegetation. A statistical method for the optimisation of plant functional types is developed in the first part. The fourth corner method by Pierre Legendre et al. was adapted to the task of grouping of plant functional types. New null models are developed for this randomisation method and their statistical properties are investigated. The mechanistical model LEGOMODEL is used to simulate the succession of plant function...

Lehsten, Veiko

2005-01-01

120

Cavity types and microclimate: implications for ecological, evolutionary, and conservation studies.  

Science.gov (United States)

The abiotic conditions of the immediate environment of organisms are key factors for a better understanding of ecological and evolutionary processes. Yet, information in this regard is biased towards some habitat types, landscapes, and organisms. Here, we present a 2-year comparative study of the microclimatic properties (temperature, relative humidity, and their fluctuation) of three cavity types (nest boxes, cavities in bridges, and burrows in sandy cliffs) in an arid environment. We found marked and consistent months-long differences in microclimate among the three cavity types. Nest boxes were colder than the other cavity types, with temperature oscillations being an order of magnitude higher than in other cavity types. In contrast, microclimate was very stable in burrows and cavities in bridges, the former being generally warmer and drier than the latter. We also discuss the biological implications of microclimatic conditions and its variation in different cavity types by presenting two case studies, namely the temperature-humidity index and water vapor pressure during the hatching period of an endotherm and the chilling period during the diapause of an ectotherm ectoparasite. We stress the need for comparative studies of the same organisms subjected to different microclimates given the important ecological, evolutionary, and conservation implications. PMID:24573376

Amat-Valero, M; Calero-Torralbo, M A; Václav, R; Valera, F

2014-11-01

 
 
 
 
121

A comparative analysis of MODIS based spectral indices for drought monitoring over fire prone vegetation types  

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Drought is a complex natural hazard with severe impacts on ecosystems. Several studies have highlighted links between drought spatio-temporal patterns and wildfire behaviour. Recent research showed drought can affect the development of catastrophic fires through influence on the spatial connectivity of dry fuel patches. Wildfires that are initiated at isolated ignition points (‘within patch scale’) can propagate non-linearly across landscapes (“among-patches”) if fuels are sufficiently dry and connected. Consequently, accurate mapping of drought at fine spatial resolution represents a priority to monitor “among-patches” continuity of flammable fuels in fire prone regions. Traditional methods of drought monitoring are based on meteorological indices (MI) calculated from weather stations data. The network of weather stations is often sparse and inadequate to produce fine spatial resolution surfaces of MI especially across remote forested areas. Spectral indices (SI) based on satellite data provide sound and cost-effective alternatives to MI, offering spatially dense information regularly recorded over large areas across a wide range of wavelengths. Since a considerable number of SI have been proposed as drought monitoring tool, the selection of the most appropriate index for a specific region represents an essential operation to ensure efficiency in drought mapping. In this study we propose a comprehensive analysis to evaluate the performance of a wide range of Vis, NIR and SWIR based SI towards drought condition monitoring over fire prone vegetation types, using the Sydney Basin bioregion (Australia) as case study. All spectral indices were derived from reflectance data sets obtained from MODIS Terra time series (2000-2009). The relationships between SI and drought conditions were analysed using a meteorological index (Standardized Precipitation Index, SPI) as rainfall deficiency indicator. The spatial and temporal co-variability between SPI and spectral indices was analysed and the sensitivity of MODIS indices to drought-related vegetation conditions was tested against a series of dry/wet years. Strong relationships between MODIS data and drought conditions were found. All spectral indices showed strong temporal and spatial correlations with SPI, with higher sensitivity to drought among SWIR based indices. The results revealed also that the spectral index routinely used by bushfire authorities in the Sydney Basin for drought monitoring is not the best indicator available, and there are potentials for the development of an enhanced MODIS-based monitoring tool. Our findings confirmed that extensive comparative analysis is necessary prior to implementation of SI in drought monitoring systems.

Caccamo, G.; Chisholm, L. A.; Bradstock, R.; Puotinen, M. L.

2010-12-01

122

Biodiesel classification by base stock type (vegetable oil) using near infrared spectroscopy data  

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The use of biofuels, such as bioethanol or biodiesel, has rapidly increased in the last few years. Near infrared (near-IR, NIR, or NIRS) spectroscopy (>4000 cm{sup -1}) has previously been reported as a cheap and fast alternative for biodiesel quality control when compared with infrared, Raman, or nuclear magnetic resonance (NMR) methods; in addition, NIR can easily be done in real time (on-line). In this proof-of-principle paper, we attempt to find a correlation between the near infrared spectrum of a biodiesel sample and its base stock. This correlation is used to classify fuel samples into 10 groups according to their origin (vegetable oil): sunflower, coconut, palm, soy/soya, cottonseed, castor, Jatropha, etc. Principal component analysis (PCA) is used for outlier detection and dimensionality reduction of the NIR spectral data. Four different multivariate data analysis techniques are used to solve the classification problem, including regularized discriminant analysis (RDA), partial least squares method/projection on latent structures (PLS-DA), K-nearest neighbors (KNN) technique, and support vector machines (SVMs). Classifying biodiesel by feedstock (base stock) type can be successfully solved with modern machine learning techniques and NIR spectroscopy data. KNN and SVM methods were found to be highly effective for biodiesel classification by feedstock oil type. A classification error (E) of less than 5% can be reached using an SVM-based approach. If computational time is an important consideration, the KNN technique (E = 6.2%) can be recommended for practical (industrial) implementation. Comparison with gasoline and motor oil data shows the relative simplicity of this methodology for biodiesel classification.

Balabin, Roman M., E-mail: balabin@org.chem.ethz.ch [Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich (Switzerland); Safieva, Ravilya Z. [Gubkin Russian State University of Oil and Gas, 119991 Moscow (Russian Federation)

2011-03-18

123

Detection of Helicobacter pylori in Various Types of Vegetables and Salads  

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Full Text Available Background:: There is a possibility for the presence of Helicobacter pylori in vegetables due to their close contact with polluted water, soil and feces. Objectives:: This study was carried out to detect the presence of H. pylori in vegetables and salads in Iran. Materials and Methods:: In total, 460 vegetable and salad samples were collected and transferred immediately to the laboratory. All samples were cultured and tested for the presence of H. pylori using the Polymerase Chain Reaction technique. Results:: The results showed that 44 of 460 samples (9.56% were positive for H. pylori using the culture method. The Polymerase Chain Reaction technique showed that 50 of 460 samples (10.86% were positive for H. pylori. Un-washed leek, traditional salad, un-washed basil and un-washed lettuce were the most commonly contaminated samples. The presence of the bacteria in various vegetables was statistically significant (P < 0.05. Conclusions:: Vegetables are a new source of H. pylori and accurate washing of vegetables improves such contaminations. Keywords: Helicobacter pylori; Vegetables; Culture; Polymerase Chain Reaction

Shahrzad Atapoor

2008-05-01

124

Ocena ranljivosti prsti in vegetacije = Evaluation of the vulnerability of soils and vegetation  

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Application of methodologyfor environmental vulnerability studies of two landscape- formingcomponents, soils and natural vegetation, is presented. Evaluation ofenvironmental vulnerability from the view of particular landscape-formingcomponent can be adjusted to different spatial levels: smallerlandscape-ecological units or larger, but still rather homogeneouslandscape-ecological types. With sufficient data it is possible quiteprecisely to evaluate environmental vulnerability on the level of l...

Barbara Lampi?

2002-01-01

125

Ecological Impacts of the Cerro Grande Fire: Predicting Elk Movement and Distribution Patterns in Response to Vegetative Recovery through Simulation Modeling October 2005  

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In May 2000, the Cerro Grande Fire burned approximately 17,200 ha in north-central New Mexico as the result of an escaped prescribed burn initiated by Bandelier National Monument. The interaction of large-scale fires, vegetation, and elk is an important management issue, but few studies have addressed the ecological implications of vegetative succession and landscape heterogeneity on ungulate populations following large-scale disturbance events. Primary objectives of this research were to identify elk movement pathways on local and landscape scales, to determine environmental factors that influence elk movement, and to evaluate movement and distribution patterns in relation to spatial and temporal aspects of the Cerro Grande Fire. Data collection and assimilation reflect the collaborative efforts of National Park Service, U.S. Forest Service, and Department of Energy (Los Alamos National Laboratory) personnel. Geographic positioning system (GPS) collars were used to track 54 elk over a period of 3+ years and locational data were incorporated into a multi-layered geographic information system (GIS) for analysis. Preliminary tests of GPS collar accuracy indicated a strong effect of 2D fixes on position acquisition rates (PARs) depending on time of day and season of year. Slope, aspect, elevation, and land cover type affected dilution of precision (DOP) values for both 2D and 3D fixes, although significant relationships varied from positive to negative making it difficult to delineate the mechanism behind significant responses. Two-dimensional fixes accounted for 34% of all successfully acquired locations and may affect results in which those data were used. Overall position acquisition rate was 93.3% and mean DOP values were consistently in the range of 4.0 to 6.0 leading to the conclusion collar accuracy was acceptable for modeling purposes. SAVANNA, a spatially explicit, process-oriented ecosystem model, was used to simulate successional dynamics. Inputs to the SAVANNA included a land cover map, long-term weather data, soil maps, and a digital elevation model. Parameterization and calibration were conducted using field plots. Model predictions of herbaceous biomass production and weather were consistent with available data and spatial interpolations of snow were considered reasonable for this study. Dynamic outputs generated by SAVANNA were integrated with static variables, movement rules, and parameters developed for the individual-based model through the application of a habitat suitability index. Model validation indicated reasonable model fit when compared to an independent test set. The finished model was applied to 2 realistic management scenarios for the Jemez Mountains and management implications were discussed. Ongoing validation of the individual-based model presented in this dissertation provides an adaptive management tool that integrates interdisciplinary experience and scientific information, which allows users to make predictions about the impact of alternative management policies.

S.P. Rupp

2005-10-01

126

Environmental controls and the influence of vegetation type, fine roots and rhizomorphs on diel and seasonal variation in soil respiration.  

Science.gov (United States)

Characterization of spatial and temporal variation of soil respiration coupled with fine root and rhizomorph dynamics is necessary to understand the mechanisms that regulate soil respiration. A dense wireless network array of soil CO2 sensors in combination with minirhizotron tubes was used to continuously measure soil respiration over 1 yr in a mixed conifer forest in California, USA, in two adjacent areas with different vegetation types: an area with woody vegetation (Wv) and an area with scattered herbaceous vegetation (Hv). Annual soil respiration rates and the lengths of fine roots and rhizomorphs were greater at Wv than at Hv. Soil respiration was positively correlated with fine roots and rhizomorphs at Wv but only with fine roots at Hv. Diel and seasonal soil respiration patterns were decoupled with soil temperature at Wv but not at Hv. When decoupled, higher soil respiration rates were observed at increasing temperatures, demonstrating a hysteresis effect. The diel hysteresis at Wv was explained by including the temperature-dependent component of soil respiration and the variation dependent on photosynthetically active radiation. The results show that vegetation type and fine root and rhizomorph dynamics influence soil respiration in addition to changes in light, temperature and moisture. PMID:19086292

Vargas, Rodrigo; Allen, Michael F

2008-07-01

127

Soil permeability as a function of vegetation type and soil water content.  

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Soil permeability is important for estimating the rate of mass transport of 222Rn through soils and into basements (Nazaroff 1992). We measured permeability and soil water content on a set of nine plots consisting of three plots vegetated with common barley (Hordeum vulgare), three plots vegetated with Russian thistle (Salsola kali), and three bare plots. Soil moisture was consistently highest on the bare plots and lowest on the Russian thistle plots. Plots with vegetation had lower soil water content during the growing season. Permeability was consistently higher on Russian thistle plots. ANOVA showed that both soil water content and presence of Russian thistle had a significant impact on permeability but that presence of barley did not. The effect of vegetation and moisture on permeability may have significant effects on 222Rn transport in soils. PMID:8181941

Morris, R C; Fraley, L

1994-06-01

128

Soil permeability as a function of vegetation type and soil water content  

International Nuclear Information System (INIS)

Soil permeability is important for estimating the rate of mass transport of 222Rn through soils and into basements. We measured permeability and soil water content on a set of nine plots consisting of three plots vegetated with common barley (Hordeum vulgare), three plots vegetated with Russian thistle (Salsola kali), and three bare plots. Soil moisture was consistently highest on the bare plots and lowest on the Russian thistle plots. Plots with vegetation had lower soil water content during the growing season. Permeability was consistently higher on Russian thistle plots. ANOVA showed that both soil water content and presence of Russian thistle had a significant impact on permeability but that presence of barley did not. The effect of vegetation and moisture on permeability may have significant effects on 222Rn transport in soils. 18 refs., 8 figs., 1 tab

129

Energy partitioning and environmental influence factors in different vegetation types in the GEWEX Asian Monsoon Experiment  

Science.gov (United States)

Environmental influences upon energy balance in areas of different vegetation types (i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand) in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature ( T), water vapor pressure deficit (VPD), soil moisture (SM), and precipitation (PPT). During May-October, the net radiation flux ( R n) (in W·m-2) was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the R n partitioned into latent heat flux ( ?E/ R n) was greater than that partitioned into sensible heat flux ( H/ R n) at Tak and at Kog-Ma. In contrast, ?E/ R n was lower than H/ R n at Arvaikheer, H/ R n was less than ?E/ R n between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R n partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer halfhourly values. At a seasonal scale energy partitions were linearly correlated (usually p<0.05) with T, VPD, and SM. The ?E/ R n increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, ?E/ R n generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, ?E/ R n was enhanced with increases of SM and T, but was decreased with VPD.

Liu, Fengshan; Tao, Fulu; Li, Shenggong; Zhang, Shuai; Xiao, Dengpan; Wang, Meng

2014-12-01

130

Ecological transcriptomics of lake-type and riverine sockeye salmon (Oncorhynchus nerka  

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Full Text Available Abstract Background There are a growing number of genomes sequenced with tentative functions assigned to a large proportion of the individual genes. Model organisms in laboratory settings form the basis for the assignment of gene function, and the ecological context of gene function is lacking. This work addresses this shortcoming by investigating expressed genes of sockeye salmon (Oncorhynchus nerka muscle tissue. We compared morphology and gene expression in natural juvenile sockeye populations related to river and lake habitats. Based on previously documented divergent morphology, feeding strategy, and predation in association with these distinct environments, we expect that burst swimming is favored in riverine population and continuous swimming is favored in lake-type population. In turn we predict that morphology and expressed genes promote burst swimming in riverine sockeye and continuous swimming in lake-type sockeye. Results We found the riverine sockeye population had deep, robust bodies and lake-type had shallow, streamlined bodies. Gene expression patterns were measured using a 16 k microarray, discovering 141 genes with significant differential expression. Overall, the identity and function of these genes was consistent with our hypothesis. In addition, Gene Ontology (GO enrichment analyses with a larger set of differentially expressed genes found the "biosynthesis" category enriched for the riverine population and the "metabolism" category enriched for the lake-type population. Conclusions This study provides a framework for understanding sockeye life history from a transcriptomic perspective and a starting point for more extensive, targeted studies determining the ecological context of genes.

Pavey Scott A

2011-12-01

131

Spatial and temporal patterns of greenness on the Yamal Peninsula, Russia: interactions of ecological and social factors affecting the Arctic normalized difference vegetation index  

International Nuclear Information System (INIS)

The causes of a greening trend detected in the Arctic using the normalized difference vegetation index (NDVI) are still poorly understood. Changes in NDVI are a result of multiple ecological and social factors that affect tundra net primary productivity. Here we use a 25 year time series of AVHRR-derived NDVI data (AVHRR: advanced very high resolution radiometer), climate analysis, a global geographic information database and ground-based studies to examine the spatial and temporal patterns of vegetation greenness on the Yamal Peninsula, Russia. We assess the effects of climate change, gas-field development, reindeer grazing and permafrost degradation. In contrast to the case for Arctic North America, there has not been a significant trend in summer temperature or NDVI, and much of the pattern of NDVI in this region is due to disturbances. There has been a 37% change in early-summer coastal sea-ice concentration, a 4% increase in summer land temperatures and a 7% change in the average time-integrated NDVI over the length of the satellite observations. Gas-field infrastructure is not currently extensive enough to affect regional NDVI patterns. The effect of reindeer is difficult to quantitatively assess because of the lack of control areas where reindeer are excluded. Many of the greenest landscapes on the Yamal are associated with landslides and drainage networks that have resulted from ongoing rapid permafrost degradation. A warming climate and enhanced winter snow awarming climate and enhanced winter snow are likely to exacerbate positive feedbacks between climate and permafrost thawing. We present a diagram that summarizes the social and ecological factors that influence Arctic NDVI. The NDVI should be viewed as a powerful monitoring tool that integrates the cumulative effect of a multitude of factors affecting Arctic land-cover change.

132

Pool-type fishways: two different morpho-ecological cyprinid species facing plunging and streaming flows.  

Science.gov (United States)

Fish are particularly sensitive to connectivity loss as their ability to reach spawning grounds is seriously affected. The most common way to circumvent a barrier to longitudinal connectivity, and to mitigate its impacts, is to implement a fish passage device. However, these structures are often non-effective for species with different morphological and ecological characteristics so there is a need to determine optimum dimensioning values and hydraulic parameters. The aim of this work is to study the behaviour and performance of two species with different ecological characteristics (Iberian barbel Luciobarbus bocagei-bottom oriented, and Iberian chub Squalius pyrenaicus-water column) in a full-scale experimental pool-type fishway that offers two different flow regimes-plunging and streaming. Results showed that both species passed through the surface notch more readily during streaming flow than during plunging flow. The surface oriented species used the surface notch more readily in streaming flow, and both species were more successful in moving upstream in streaming flow than in plunging flow. Streaming flow enhances upstream movement of both species, and seems the most suitable for fishways in river systems where a wide range of fish morpho-ecological traits are found. PMID:23741465

Branco, Paulo; Santos, José M; Katopodis, Christos; Pinheiro, António; Ferreira, Maria T

2013-01-01

133

Habitat suitability and ecological niches of different plankton functional types in the global ocean  

Science.gov (United States)

Marine plankton play a central role in the biogeochemical cycling of important elements such as carbon, nitrogen, and sulphur. While our knowledge about marine ecosystem structure and functioning is still scarce and episodic, several recent observational studies confirm that marine ecosystems have been changing due to recent climate change, overfishing, and coastal eutrophication. In order to better understand marine ecosystem dynamics, the MAREDAT initiative has recently collected abundance and biomass data for 5 autotrophic (diatoms, Phaeocystis, coccolithophores, nitrogen fixers, picophytoplankton), and 6 heterotrophic plankton functional types (PFTs; bacteria, micro-, meso- and macrozooplankton, foraminifera and pteropods). Species distribution models (SDMs) are statistical tools that can be used to derive information about species habitats in space and time. They have been used extensively for a wide range of ecological applications in terrestrial ecosystems, but here we present the first global application in the marine realm, which was made possible by the MAREDAT data synthesis effort. We use a maximum entropy SDM to simulate global habitat suitability, habitat extent and ecological niches for different PFTs in the modern ocean. Present habitat suitability is derived from presence-only MAREDAT data and the observed annual and monthly mean levels of physiologically relevant variables such as SST, nutrient concentration or photosynthetic active radiation received in the mixed layer. This information can then be used to derive ecological niches for different species or taxa within each PFT, and to compare the ecological niches of different PFTs. While these results still need verification because data was not available for all ocean regions for all PFTs, they can give a first indication what present and future plankton habitats may look like, and what consequences we may have to expect for future marine ecosystem functioning and service provision in a warmer world.

Vogt, Meike; Brun, Philipp; Payne, Mark R.; O'Brien, Colleen J.; Bednaršek, Nina; Buitenhuis, Erik T.; Doney, Scott C.; Leblanc, Karine; Le Quéré, Corinne; Luo, Yawei; Moriarty, Róisín; O'Brien, Todd D.; Schiebel, Ralf; Swan, Chantal

2013-04-01

134

The historical ecology of Namibian rangelands: vegetation change since 1876 in response to local and global drivers.  

Science.gov (United States)

The influence of both local and global drivers on long-term changes in the vegetation of Namibia's extensive rangelands was investigated. Fifty-two historical photographs of the Palgrave Expedition of 1876 were re-photographed and used to document changes over more than 130 years, in grass, shrub and tree cover within three major biomes along a 1200km climatic gradient in central and southern Namibia. We showed that patterns of change are correlated with mean annual precipitation (MAP) and that below a threshold of around 250mm, vegetation has remained remarkably stable regardless of land-use or tenure regime. Above this threshold, an increase in tree cover is linked to the rainfall gradient, the legacies of historical events in the late 19th century, subsequent transformations in land-use and increased atmospheric CO(2). We discuss these findings in relation to pastoral and settler societies, paleo- and historical climatic trends and predictions of vegetation change under future global warming scenarios. We argue that changes in land-use associated with colonialism (decimation of megaherbivores and wildlife browsers; fire suppression, cattle ranching), as well as the effects of CO(2) fertilisation provide the most parsimonious explanations for vegetation change. We found no evidence that aridification, as projected under future climate change scenarios, has started in the region. This study provided empirical evidence and theoretical insights into the relative importance of local and global drivers of change in the savanna environments of central and southern Namibia and global savanna ecosystems more generally. PMID:22188617

Rohde, Richard F; Hoffman, M Timm

2012-02-01

135

Wild fire effects on floristic diversity in three thermo-Mediterranean vegetation types in a small islet of eastern Aegean sea  

Science.gov (United States)

Sclerophyllus scrub formations, the main vegetation type in many islands of the Aegean area, are characterized by their high biodiversity. Dominant shrub species of sclerophyllus formations are well adapted to dry season conditions by various anatomical and physiological mechanisms. As a result, their biomass acts as very flammable fine fuel, and consequently wild fires are very common in these ecosystems. Wildfire effects on vegetation and biodiversity in the Mediterranean basin have been studied and the results are diverse depending mainly on vegetation type and frequency of fire. The aim of this study was to evaluate the effects of wildfire on floristic diversity and species composition in three thermo-Mediterranean vegetation types 1) Sacropoterium spinosum phrygana, 2) low formations of Cistus creticus and 3) low formations of Cistus creticus in abandoned terraces. The research was conducted in Enoussa islet, which is located northeastern of Chios Island, in May 2013 (one year after the fire). Vegetation sampling was performed along five transects placed in recently burned and in adjacent unburned sites of each vegetation type. The plant cover and the floristic composition were measured, while diversity, evenness and dominance indices were determined for the vegetation data. Vegetation cover and the floristic diversity were significant lower and higher respectively in burned areas in comparison to the unburned. The woody species followed by the annual grasses and the annual forbs dominated in both burned and unburned areas. However, the woody species were significantly decreased in the burned areas in all vegetation types, while the annual grasses only in the burned areas of Sacropoterium spinosum phrygana and Cistus creticus in abandoned terraces. Inversely, the annual forbs significantly increased in the burned sites of Cistus creticus formations. The highest value of Morisita-Horn Index of similarity between burned and unburned sites (beta diversity) was observed for the Sacropoterium spinosum phrygana (0.83) indicating limited effect of fire on the species composition of this vegetation type.

Abraham, Eleni; Kyriazopoulos, Apostolos; Korakis, George; Parissi, Zoi; Chouvardas, Dimitrios

2014-05-01

136

Physical rehabilitation of students of medical groups with the disease vegetative-vascular dystonia for mixed type.  

Directory of Open Access Journals (Sweden)

Full Text Available Consider the problem of declining levels of health of students I-II courses that are assigned to special medical group. Substantiated the importance of including health improvement-rehabilitation program for students with the disease vegetative-vascular dystonia of mixed type. Define oriented content rehabilitation programs for this group of individuals. The program improves the functional and psychological status of students, to carry out prevention of autonomic crises. Proved the prevalence and increase with each passing year the number of people with vascular dystonia of mixed type of students - 50-55%.

?lchovik Alina Vitalievna

2011-10-01

137

A new quantitative classification of ecological types in the bromeliad genus Tillandsia (Bromeliaceae based on trichomes  

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Full Text Available Using collection specimens, we measured the density and wing area of trichomes in 37 species of the bromeliad genus Tillandsia, specifically the abaxial proximal, abaxial distal, adaxial proximal and adaxial distal parts of the leaf. The product of the trichome "wing" area by the number of trichomes (means produced a pure number (T that was correlated to ecological features. The correlation was positive with respect to arid environments (xeric Tillands and negative with respect to humid environments (mesic Tillands. Bulbous, and particularly myrmecophytic species and species with tanks, represented particular categories. Other intermediate types were identified based on the T number, totalling five ecological types. In comparison with other systems of ecological typification for Tillands and other Bromeliaceae, the present system offers measurable data whose analysis is reproducible. Rev. Biol. Trop. 56 (1: 191-203. Epub 2008 March 31.Medimos el número por milímetro cuadrado y el área del "ala" (parte móvil de los tricomas en las partes adaxial próxima y distal, y adaxial próxima y distal, de la hoja de 37 especies de bromelias del género Tillandsia. El producto del área del ala para el número de los tricomas (promedio produjo un número puro (T. Hallamos que T se correlaciona con las características ecológicas de las tilandsias investigadas. La correlación es positiva con respecto a ambientes áridos (especies xéricas y negativa con respecto a los ambientes húmedos (especies mésicas. Las especies con bulbo, y particularmente las asociadas con hormigas y especies con de tanque representan categorías particulares. Identificamos otros tipos intermedios, agradando así cinco tipos ecológicos. En comparación con otros sistemas de tipificación ecológica, este sistema ofrece la ventaja de ser reproducible y cuantitativo.

Mosti Stefano

2008-03-01

138

Fruit and vegetable intake and type 2 diabetes : EPIC-InterAct prospective study and meta-analysis  

DEFF Research Database (Denmark)

Fruit and vegetable intake (FVI) may reduce the risk of type 2 diabetes (T2D), but the epidemiological evidence is inconclusive. The aim of this study is to examine the prospective association of FVI with T2D and conduct an updated meta-analysis. In the European Prospective Investigation into Cancer-InterAct (EPIC-InterAct) prospective case-cohort study nested within eight European countries, a representative sample of 16?154 participants and 12?403 incident cases of T2D were identified from 340?234 individuals with 3.99 million person-years of follow-up. For the meta-analysis we identified prospective studies on FVI and T2D risk by systematic searches of MEDLINE and EMBASE until April 2011. In EPIC-InterAct, estimated FVI by dietary questionnaires varied more than twofold between countries. In adjusted analyses the hazard ratio (95% confidence interval) comparing the highest with lowest quartile of reported intake was 0.90 (0.80-1.01) for FVI; 0.89 (0.76-1.04) for fruit and 0.94 (0.84-1.05) for vegetables. Among FV subtypes, only root vegetables were inversely associated with diabetes 0.87 (0.77-0.99). In meta-analysis using pooled data from five studies including EPIC-InterAct, comparing the highest with lowest category for FVI was associated with a lower relative risk of diabetes (0.93 (0.87-1.00)). Fruit or vegetables separately were not associated with diabetes. Among FV subtypes, only green leafy vegetable (GLV) intake (relative risk: 0.84 (0.74-0.94)) was inversely associated with diabetes. Subtypes of vegetables, such as root vegetables or GLVs may be beneficial for the prevention of diabetes, while total FVI may exert a weaker overall effect.European Journal of Clinical Nutrition advance online publication, 1 August 2012; doi:10.1038/ejcn.2012.85.

Cooper, A J; Forouhi, N G

2012-01-01

139

Morpho?ecological characterization of the peniche?baleal dune system (portuguese west coast  

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Full Text Available the Peniche?Baleal coastal dune system has a strategic importance on regional development, marked by considerable investment in tourism and recreational sectors. the increasing human impact on this coastal dune system caused by human trampling tends to modify its geomorphological and ecological degradation, namely sand dune vegetation reduction. the morpho?ecological characterization of the coastal dune system was accomplished by six morpho?ecological profiles as well as data from field surveys that allowed the (i haracterisation of foredune morphology and coastal dune system morphology; (ii identification of different morpho?ecological coastal dunes types; (iii identification of sand dune vegetation diversity and main spatial mosaics; (iv identification of sand dune species of the different morpho?ecological costal dunes types. as a result, sand dune vegetation shows high biodiversity and good conservation conditions especially landward. it is possible to identify two important Portuguese endemic sand dune species – Armeria welwitschii and Verbascum litigiosum – with legal protection status.

Raquel Paixão

2013-06-01

140

Residues and potential ecological risks of veterinary antibiotics in manures and composts associated with protected vegetable farming.  

Science.gov (United States)

Veterinary antibiotics (VAs) are emerging contaminants and enter into soil principally by agricultural application of organic fertilizer. A total of 33 solid animal manures and 17 compost samples from protected vegetable farms in nine areas of China were analyzed for the antibiotic classes of tetracyclines, fluoroquinolones, sulfonamides, and macrolides (17 substances in total). Oxytetracycline was found as a dominant compound in the samples, and its highest concentration reached 416.8 mg kg(-1) in a chicken manure sample from Shouguang, Shandong Province. Among the samples, animal manures (especially pig manure) contained higher VA residues than composts. However, fluoroquinolones exhibited higher persistence in the compost samples than other antibiotic classes. This is particularly the case in the rice husk compost, which contained the highest level of ofloxacin and ciprofloxacin (1334.5 and 1717.4 ?g kg(-1) on average, respectively). The veterinary antibiotic profile in the risk husk compost had a good relationship with that in the corresponding manures. The refined commercial compost had the lowest VA residues among the compost samples in general. This implied that composting process might be important to reduce the antibiotic residue. High residue of antibiotics in soil was assumed to be a hazard to ecosystem. This is especially noticeable under current application rates (150 t ha(-1) a(-1)) in protected vegetable farming because over half of the samples exhibited a risk quotient (RQ) >1 for one or more antibiotics. PMID:25354434

Zhang, Haibo; Luo, Yongming; Wu, Longhua; Huang, Yujuan; Christie, Peter

2014-10-30

 
 
 
 
141

Epidemiology and ecology of type 1 diabetes mellitus in children and adolescents of Krasnodar Region  

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Full Text Available Aims. to investigate the influence of environmental pollution on epidemiology of type 1 diabetes mellitus (T1DM in children and adolescents of Krasnodar Region.Materials and Methos. Epidemiologic study was based on regional T1DM register data and official reports by medical facilities (form #112. Environmental survey was conducted according to the method of Shashel et al.Results. Epidemiologic study revealed increasing prevalence of T1DM among children and adolescents of Krasnodar Region for the period from 2000 to 2012 yy. Average prevalence of T1DM was estimated at 68.08 (children and 135.78 (adolescents, and incidence at 10.08 and 17.01 per 100 000 inhabitants, respectively. Epidemiologic trend quantitatively correlates with ecological disturbance in resident areas of the population in question. Areas recognized as adverse environment reported a 2.8–3.2-fold increase in T1DM appealability as measured against neighboring areas with favourable ecologic environment. Conclusion. Higher levels of environmental pollution drive both incidence and prevalence of T1DM in children and adolescents of Krasnodar Region, plausibly through induction of autoimmune process in the pancreas.

Irina Yur'evna Chernyak

2013-11-01

142

Untangling the role of elevation, aspect, and vegetation type on ecohydrological dynamics along a climate gradient in the Alps  

Science.gov (United States)

Vegetation dynamics and performance are strongly influenced by environmental conditions. Specifically, light, precipitation, and air temperature exert a predominant role. These climatic variables covariate with elevation and aspect in areas of complex terrain. Quantification of specific elevation and aspect effects on vegetation productivity and mass and energy fluxes can lead to a better understating of environment-driven distribution of vegetation and parsimonious up-scaling parameterizations useful in hydrological applications. A detailed characterization of climatic differences with elevation is however a daunting task. In this study, two synthetic climate gradients, constructed using hourly meteorological data and a stochastic weather generator, AWE-GEN, are used to force a mechanistic ecohydrological model, Tethys-Chloris, and quantify energy, carbon, and water fluxes for three generic Plant Functional Types (PFTs). One gradient is representative of a dry, sheltered alpine valley (Valais), whereas the other one characterizes a wet, exposed mountain side (Bernese Oberland). Thirty year long time series of cross-correlated precipitation, air temperature, relative humidity, wind speed, solar radiation, and atmospheric pressure for elevation bands from 500 up to 3500 m a.s.l. are generated to represent the climatic differences. The incoming radiation is successively recalculated for different combinations of aspect and slope. Under these specific climatic forcing conditions, the response of deciduous and evergreen trees, and grass typical of the Alpine system is investigated. The parameterization of the ecohydrological model was tested to reproduce vegetation productivity and energy fluxes for several locations in an Alpine climate or similar conditions (Fluxnet dataset) and to correctly simulate snowpack dynamics for forested and open sites worldwide (Snowmip-2 dataset). The three PFTs evolve at different elevations and aspects for dry and wet conditions. Results indicate that differences in hydrological fluxes across PFTs are more evident for the dry, water-limited scenario, rather than for the wet scenario. The optimum for vegetation productivity shifts from low elevations of 500-1000 m in wet conditions to higher elevations (of about 1800-2200 m) for the dry altitudinal gradient. By intercepting snow and shading ground surface, PFTs affect differently snow cover distribution and seasonal duration. The overall role of elevation was found to be predominant when compared to the role of aspect, regardless of the climate type. Nonetheless, we speculate that this is not always the case and the role of aspect, or contributing area might become the dominant control for different ecosystems.

Fatichi, S.; Ivanov, V. Y.; Rimkus, S.; Caporali, E.; Burlando, P.

2012-04-01

143

Landscape object-based analysis of wetland plant functional types: the effects of spatial scale, vegetation classes and classifier methods  

Science.gov (United States)

Remote sensing-based vegetation classifications representing plant function such as photosynthesis and productivity are challenging in wetlands with complex cover and difficult field access. Recent advances in object-based image analysis (OBIA) and machine-learning algorithms offer new classification tools; however, few comparisons of different algorithms and spatial scales have been discussed to date. We applied OBIA to delineate wetland plant functional types (PFTs) for Poyang Lake, the largest freshwater lake in China and Ramsar wetland conservation site, from 30-m Landsat TM scene at the peak of spring growing season. We targeted major PFTs (C3 grasses, C3 forbs and different types of C4 grasses and aquatic vegetation) that are both key players in system's biogeochemical cycles and critical providers of waterbird habitat. Classification results were compared among: a) several object segmentation scales (with average object sizes 900-9000 m2); b) several families of statistical classifiers (including Bayesian, Logistic, Neural Network, Decision Trees and Support Vector Machines) and c) two hierarchical levels of vegetation classification, a generalized 3-class set and more detailed 6-class set. We found that classification benefited from object-based approach which allowed including object shape, texture and context descriptors in classification. While a number of classifiers achieved high accuracy at the finest pixel-equivalent segmentation scale, the highest accuracies and best agreement among algorithms occurred at coarser object scales. No single classifier was consistently superior across all scales, although selected algorithms of Neural Network, Logistic and K-Nearest Neighbors families frequently provided the best discrimination of classes at different scales. The choice of vegetation categories also affected classification accuracy. The 6-class set allowed for higher individual class accuracies but lower overall accuracies than the 3-class set because individual classes differed in scales at which they were best discriminated from others. Main classification challenges included a) presence of C3 grasses in C4-grass areas, particularly following harvesting of C4 reeds and b) mixtures of emergent, floating and submerged aquatic plants at sub-object and sub-pixel scales. We conclude that OBIA with advanced statistical classifiers offers useful instruments for landscape vegetation analyses, and that spatial scale considerations are critical in mapping PFTs, while multi-scale comparisons can be used to guide class selection. Future work will further apply fuzzy classification and field-collected spectral data for PFT analysis and compare results with MODIS PFT products.

Dronova, I.; Gong, P.; Wang, L.; Clinton, N.; Fu, W.; Qi, S.

2011-12-01

144

On the potential vegetation feedbacks that enhance phosphorus availability - insights from a process-based model linking geological and ecological timescales  

Science.gov (United States)

In old and heavily weathered soils, the availability of P might be so small that the primary production of plants is limited. However, plants have evolved several mechanisms to actively take up P from the soil or mine it to overcome this limitation. These mechanisms involve the active uptake of P mediated by mycorrhiza, biotic de-occlusion through root clusters, and the biotic enhancement of weathering through root exudation. The objective of this paper is to investigate how and where these processes contribute to alleviate P limitation on primary productivity. To do so, we propose a process-based model accounting for the major processes of the carbon, water, and P cycles including chemical weathering at the global scale. Implementing P limitation on biomass synthesis allows the assessment of the efficiencies of biomass production across different ecosystems. We use simulation experiments to assess the relative importance of the different uptake mechanisms to alleviate P limitation on biomass production. We find that active P uptake is an essential mechanism for sustaining P availability on long timescales, whereas biotic de-occlusion might serve as a buffer on timescales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modelling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth), and that vegetation on old soils has a smaller biomass production rate when P becomes limiting. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and ecological timescales under different environmental settings.

Buendía, C.; Arens, S.; Hickler, T.; Higgins, S. I.; Porada, P.; Kleidon, A.

2014-07-01

145

Tidal Creek Morphology and Sediment Type Influence Spatial Trends in Salt Marsh Vegetation  

DEFF Research Database (Denmark)

Zonal patterns of salt marsh plants and physical conditions have been addressed primarily across the elevation gradient from inland to coastline rather than across tidal creeks in relation to their hydro-geomorphic processes such as bar formation and bank erosion. We found at a Danish marsh that by shaping major geomorphic features and providing sediments to the adjacent sites, fluvial-geomorphic processes of tidal creeks exert fundamental controls on the cross-channel distribution of abiotic and biotic factors. These results point to a need for biogeomorphic and landscape ecological perspectives to fully understand the underlying structure and geographic variability in salt marshes.

Kim, Daehyun; Cairns, David M.

2013-01-01

146

Differences in organotin accumulation among ecological migratory types of the Japanese eel Anguilla japonica  

Science.gov (United States)

In order to examine the ecological risks caused by organotin compounds (OTs) in diadromous fish migrating between sea and freshwater, tributyltin (TBT) and triphenyltin (TPT) compounds, and their breakdown products, were determined in the catadromous eel Anguilla japonica having sea, estuarine and river life histories, collected in Japanese sea, brackish and fresh waters. Ontogenic changes in otolith strontium (Sr) and calcium (Ca) concentrations were examined along life history transect to discriminate the migration type. There were generally three different patterns, which were categorized 'sea eels' (spent most of their life in the sea and did not enter freshwater), 'estuarine eels' (inhabited estuaries or switched between different habitats), and 'river eels' (entered and remained in freshwater river habitats after arrival in the estuary) according to the otolith Sr:Ca ratio. There were generally no significant correlations between TBT and TPT accumulation and various biological characteristics such as total length (TL), body weight (BW), age and sex in A. japonica. The concentrations of TBT and TPT in silver eels (mature eels) were significantly higher than those in yellow eels (immature eels), and the percentages of TBT and TPT were also higher in silver eels than in yellow eels. A positive correlation was found between TBT concentration and the gonad-somatic index (GSI). It is thus considered that silver eels have a higher risk of contamination by TBT than yellow eels. TBT and TPT concentrations in sea eels were significantly higher than those in river eels. In contrast, no significant differences were observed in TBT and TPT concentrations in estuarine eels compared to sea and river eels. These results suggest that sea eels have a higher ecological risk of OT contamination than river eels during their life history, and the risk of OTs in estuarine eels is considered to be intermediate between that of sea and river eels. Positive linear relationships were found between Sr:Ca ratios and the concentrations of TBT and TPT. Therefore, these results suggest that the ecological risk of OTs increase, as the sea residence period in the eel become longer. Even at the same maturation stage, TBT and TPT concentrations in sea eels were significantly higher than those in river eels. Thus, it is clear that migratory type is a more important factor for OT accumulation than maturation stage.

Ohji, Madoka; Harino, Hiroya; Arai, Takaomi

2006-08-01

147

Relationships between vegetation and terrain variables in southeastern Arizona. Ph.D. Thesis  

Science.gov (United States)

The author has identified the following significant results. Relationships were established between eight terrain variables and plant species and 31 vegetation types. Certain plant species are better than others for differentiating or discriminating groups of specified terrain variables. Certain terrain variables are better than others for differentiating or discriminating groups of vegetation types. Stepwise discriminant analysis was shown to be a useful tool in plant ecological studies.

Mouat, D. A. (principal investigator)

1974-01-01

148

Pollination ecology of Tabebuia aurea (Manso) Benth. & Hook. and T. ochracea (Cham.) Standl. (Bignoniaceae) in Central Brazil cerrado vegetation Ecologia da polinização de Tabebuia aurea (Manso) Benth. & Hook. e T. ochracea (Cham.) Standl. (Bignoniaceae) em cerrado do Brasil Central  

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The pollination ecology and breeding systems of Tabebuia aurea (Manso) Benth. & Hook., and T. ochracea (Cham.) Standl. were investigated in an area of cerrado vegetation in the Federal District of Brazil. These species occur sympatrically, flower massively and synchronously for a month, during the dry season (July to September). Both have diurnal anthesis, with similar floral structures, a yellow tubular corolla and produce nectar. Fourteen species of bees visited both Tabebuia species, but, ...

MARILUZA GRANJA BARROS

2001-01-01

149

Distribution of phytoplankton functional types in high-nitrate, low-chlorophyll waters in a new diagnostic ecological indicator model  

Science.gov (United States)

Modeling and monitoring plankton functional types (PFTs) is challenged by the insufficient amount of field measurements of ground truths in both plankton models and bio-optical algorithms. In this study, we combine remote sensing data and a dynamic plankton model to simulate an ecologically sound spatial and temporal distribution of phyto-PFTs. We apply an innovative ecological indicator approach to modeling PFTs and focus on resolving the question of diatom-coccolithophore coexistence in the subpolar high-nitrate and low-chlorophyll regions. We choose an artificial neural network as our modeling framework because it has the potential to interpret complex nonlinear interactions governing complex adaptive systems, of which marine ecosystems are a prime example. Using ecological indicators that fulfill the criteria of measurability, sensitivity and specificity, we demonstrate that our diagnostic model correctly interprets some basic ecological rules similar to ones emerging from dynamic models. Our time series highlight a dynamic phyto-PFT community composition in all high-latitude areas and indicate seasonal coexistence of diatoms and coccolithophores. This observation, though consistent with in situ and remote sensing measurements, has so far not been captured by state-of-the-art dynamic models, which struggle to resolve this "paradox of the plankton". We conclude that an ecological indicator approach is useful for ecological modeling of phytoplankton and potentially higher trophic levels. Finally, we speculate that it could serve as a powerful tool in advancing ecosystem-based management of marine resources.

Palacz, A. P.; St. John, M. A.; Brewin, R. J. W.; Hirata, T.; Gregg, W. W.

2013-11-01

150

Distribution of phytoplankton functional types in high-nitrate low-chlorophyll waters in a new diagnostic ecological indicator model  

DEFF Research Database (Denmark)

Modeling and monitoring plankton functional types (PFTs) is challenged by insufficient amount of field measurements to ground-truth both plankton models and bio-optical algorithms. In this study, we combine remote sensing data and a dynamic plankton model to simulate an ecologically-sound spatial and temporal distribution of phyto-PFTs. We apply an innovative ecological indicator approach to modeling PFTs, and focus on resolving the question of diatom-coccolithophore co-existence in the subpolar high-nitrate and low-chlorophyll regions. We choose an artificial neural network as our modeling framework because it has the potential to interpret complex nonlinear interactions governing complex adaptive systems, of which marine ecosystems are a prime example. Using ecological indicators that fulfill the criteria of measurability, sensitivity and specificity, we demonstrate that our diagnostic model correctly interprets some basic ecological rules similar to ones emerging from dynamic models. Our time series highlight a dynamic phyto-PFT community composition in all high latitude areas, and indicate seasonal co-existence of diatoms and coccolithophores. This observation, though consistent with in situ and remote sensing measurements, was so far not captured by state-of-the-art dynamic models which struggle to resolve this "paradox of the plankton". We conclude that an ecological indicator approach is useful for ecological modeling of phytoplankton and potentially higher trophic levels. Finally, we speculate that it could serve as a powerful tool in advancing ecosystem-based management of marine resources

Palacz, Artur; St. John, Michael

2013-01-01

151

The impact of greenhouse vegetable farming duration and soil types on phytoavailability of heavy metals and their health risk in eastern China.  

Science.gov (United States)

Heavy metal contamination in vegetables from greenhouse vegetable production (GVP) in China requires major attention. For GVP sustainability at a large regional level, 441 surface GVP soil and 132 corresponding greenhouse vegetable samples were collected from six typical GVP bases in eastern China to systematically evaluate the impact of GVP duration and soil types (Anthrosols and Cambosols) on phytoavailability of four major metals, Cd, Cu, Zn, and Pb, and their health risk. The results revealed high Cd accumulation in leaf vegetables grown in Anthrosols, which might pose potential health risk. Regardless of soil types in the study region, greenhouse farming lowered soil pH and enhanced metal availability with rising GVP duration, which might exacerbate Cd phytoavailability and vegetable Cd contamination as well as potential health risk. Also, increased GVP soil organic matter contents over time, found in some locations, affected crop-depending Cu and Zn uptakes. Furthermore, due to GVP, the annual decrease rate of soil pH and increase rates of soil available metal concentrations were generally much greater in Anthrosols than those in Cambosols, which contributed a lot to high Cd uptake by leaf vegetables grown in Anthrosols and their potential health risk. From sustainable GVP perspective, fertilization strategy with reduced frequency and rate is especially important and effective for abating soil and vegetable contamination by heavy metals under greenhouse farming. PMID:24331873

Yang, Lanqin; Huang, Biao; Hu, Wenyou; Chen, Yong; Mao, Mingcui; Yao, Lipeng

2014-05-01

152

Pollen-based quantitative reconstructions of Holocene regional vegetation cover (plant-functional types and land-cover types) in Europe suitable for climate modelling.  

Science.gov (United States)

We present quantitative reconstructions of regional vegetation cover in north-western Europe, western Europe north of the Alps, and eastern Europe for five time windows in the Holocene [around 6k, 3k, 0.5k, 0.2k, and 0.05k calendar years before present (bp)] at a 1° × 1° spatial scale with the objective of producing vegetation descriptions suitable for climate modelling. The REVEALS model was applied on 636 pollen records from lakes and bogs to reconstruct the past cover of 25 plant taxa grouped into 10 plant-functional types and three land-cover types [evergreen trees, summer-green (deciduous) trees, and open land]. The model corrects for some of the biases in pollen percentages by using pollen productivity estimates and fall speeds of pollen, and by applying simple but robust models of pollen dispersal and deposition. The emerging patterns of tree migration and deforestation between 6k bp and modern time in the REVEALS estimates agree with our general understanding of the vegetation history of Europe based on pollen percentages. However, the degree of anthropogenic deforestation (i.e. cover of cultivated and grazing land) at 3k, 0.5k, and 0.2k bp is significantly higher than deduced from pollen percentages. This is also the case at 6k in some parts of Europe, in particular Britain and Ireland. Furthermore, the relationship between summer-green and evergreen trees, and between individual tree taxa, differs significantly when expressed as pollen percentages or as REVEALS estimates of tree cover. For instance, when Pinus is dominant over Picea as pollen percentages, Picea is dominant over Pinus as REVEALS estimates. These differences play a major role in the reconstruction of European landscapes and for the study of land cover-climate interactions, biodiversity and human resources. PMID:25204435

Trondman, A-K; Gaillard, M-J; Mazier, F; Sugita, S; Fyfe, R; Nielsen, A B; Twiddle, C; Barratt, P; Birks, H J B; Bjune, A E; Björkman, L; Broström, A; Caseldine, C; David, R; Dodson, J; Dörfler, W; Fischer, E; van Geel, B; Giesecke, T; Hultberg, T; Kalnina, L; Kangur, M; van der Knaap, P; Koff, T; Kuneš, P; Lagerås, P; Lata?owa, M; Lechterbeck, J; Leroyer, C; Leydet, M; Lindbladh, M; Marquer, L; Mitchell, F J G; Odgaard, B V; Peglar, S M; Persson, T; Poska, A; Rösch, M; Seppä, H; Veski, S; Wick, L

2015-02-01

153

Série temporal de índice de vegetação sobre diferentes tipologias vegetais no Rio Grande do Sul / Time series of vegetation index for different vegetation types in Rio Grande do Sul  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Com este trabalho objetivou-se identificar a dinâmica fenológica das principais tipologias vegetais do Rio Grande do Sul, para o período de 2000 a 2010, utilizando-se dados de Enhanced Vegetation Index, através da transformada de ondaleta. A identificação da fenologia em ciclos ou padrões sazonais e [...] m séries temporais de índices de vegetação, obtidos por sensores orbitais, permite a observação de anomalias e os efeitos de mudanças climáticas ou ambientais. Um perfil temporal do Enhanced Vegetation Index foi construído para o Rio Grande do Sul e retiradas amostras para quatro tipologias vegetais: campo nativo, floresta ombrófila mista, cultivo de soja e de arroz. Essas amostras foram submetidas à transformada de ondaleta, que permitiu a decomposição da série e apresentação dos dados em relação ao tempo e frequência com que os eventos fenológicos ocorreram. Os dados apresentaram regularidade na dinâmica das tipologias vegetais testadas, com ciclos anuais de maior vigor e crescimento vegetal nas estações de primavera e verão e menor no outono e inverno. Abstract in english The objective of this study was the identification of the phenology dynamics of the main types of vegetation of Rio Grande do Sul state, for the period from 2000 to 2010, using Enhanced Vegetation Index data through the wavelet transform. The identification of cycles or seasonal patterns in time ser [...] ies of vegetation indices obtained by orbital sensors allows the observation of anomalies and effects of climate and environmental change. A temporal profile of Enhanced Vegetation Index was built for the Rio Grande do Sul region, where samples of the four main plant typologies were selected: native grassland, mixed ombrophilous forest, soybean and rice crop. These samples were submitted to the wavelet transform, which allowed the decomposition of the series and presentation of data in relation to time and frequency with which the phenological events have occurred. The data showed regularity in the dynamics of vegetation types tested, with annual cycles of plant growth and higher Enhanced Vegetation Index values in spring and summer and lower Enhanced Vegetation Index values in autumn and winter.

Tatiana M., Kuplich; Andreise, Moreira; Denise C., Fontana.

1116-11-01

154

Feed intake and activity level of two broiler genotypes foraging different types of vegetation in the finishing period  

DEFF Research Database (Denmark)

A study was performed with 2 broiler genotypes (slow and medium growth) restricted in supplementary feed and foraging 2 different mixed vegetations (grass/clover or chicory) to identify possible benefits of herbage on nutrition during the finishing period (80 to 113 d of age). Three hundred birds were included in a 2 × 2 factorial design with groups of 25 birds replicated 3 times. The use of outdoor areas, performance, and forage intake were investigated. To identify possible differences in foraging activity, the use of the range was monitored one day per week at 4 different times of the day. Feed intake from foraging was estimated by killing 4 birds per plot (2 males and 2 females) in the morning and in the evening on 3 d during the experiment and measuring crop content. Vegetation type did not influence broiler use of the free-range area, feed intake, or performance. Differences in the use of the range area, activity level, and feed content in the crops were observed in relation to genotype, sex, age of broilers, and also the time of day. Foraging activity was positively correlated with age. Medium-growth broilers spent more time inside and closer to the broiler houses during the day with increased foraging activity during evenings, in contrast to the slow-growing broilers that showed a more uniform activity during the day. Based on the measurement of crop content it was estimated that the slow-growing genotype had a daily intake of 5 to 8 g of forage per day, whereas the medium-growing genotype had an intake of 9 g for females and 20 g for males. In conclusion, limitation of supplemented protein feed in the finishing period may be acceptable for broilers that have access to highly nutritious vegetation.

Almeida, Gustavo Fonseca; Hinrichsen, Lena Karina

2012-01-01

155

Ecological and socioeconomic correlates of fruit, juice, and vegetable consumption among African-American boys. — Measures of the Food Environment  

Science.gov (United States)

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156

Vegetation associated with the occurrence of the Brenton blue butterfly  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english The Brenton blue butterfly, Orachrysops niobe (Trimen), is critically endangered and known only from one site near Knysna in the Western Cape province of South Africa, now proclaimed as the Brenton Blue Butterfly Reserve (BBBR). We have explored associations between vegetation types and the presence [...] of O. niobe's only host plant, Indigofera erecta (Thunb.), using Braun-Blanquet vegetation classification and ordination techniques as part of a broader research project at the BBBR. Positive correlations are demonstrated between the occurrence of I. erecta and certain thicket vegetation types dominated by Pterocelastrus tricuspidatus (candlewood trees). Ordinations using soil analysis and slope data have not detected significant environmental gradients influencing vegetation types. The high degree of vegetation heterogeneity at the BBBR appears to be driven in part by various disturbance histories. Historical ecological events at the site such as fire and megaherbivore impacts, and their role in sustaining the ideal habitat for I. erecta and O. niobe, are discussed. Management techniques for the BBBR such as controlled fires or the cutting of paths through the vegetation are evaluated and an optimum future management strategy is recommended. This is the most comprehensive vegetation study ever carried out at the habitat of an endangered butterfly in South Africa, and breaks new ground by using vegetation analysis to develop a well-informed management plan for conservation of this species. It has significance for the management of small sites where many such endangered butterflies occur.

D.A., Edge; S.S., Cilliers; R.F., Terblanche.

2008-12-01

157

Design and Development of a Spectral Library for Different Vegetation and Landcover Types for Arctic, Antarctic and Chihuahua Desert Ecosystem  

Science.gov (United States)

All objects on the Earth's surface absorb and reflect portions of the electromagnetic spectrum. Depending on the composition of the material, every material has its characteristic spectral profile. The characteristic spectral profile for vegetation is often used to study how vegetation patterns at large spatial scales affect ecosystem structure and function. Analysis of spectroscopic data from the laboratory, and from various other platforms like aircraft or spacecraft, requires a knowledge base that consists of different characteristic spectral profiles for known different materials. This study reports on establishment of an online and searchable spectral library for a range of plant species and landcover types in the Arctic, Anatarctic and Chihuahuan desert ecosystems. Field data were collected from Arctic Alaska, the Antarctic Peninsula and the Chihuahuan desert in the visible to near infrared (IR) range using a handheld portable spectrometer. The data have been archived in a database created using postgre sql with have been made publicly available on a plone web-interface. This poster describes the data collected in more detail and offers instruction to users who wish to make use of this free online resource.

Matharasi, K.; Goswami, S.; Gamon, J.; Vargas, S.; Marin, R.; Lin, D.; Tweedie, C. E.

2008-12-01

158

Vegetation patterns and dynamics on a rock glacier in the Northern Apennines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The vegetation colonizing a rock glacier in the north-western cirque of M. Giovo (Northern Apennines) was recorded according to the Braun-Blanquet method. Numerical methods were employed both to classify and to order the phytosociological relevés. Relevés were classified by average linkage based on the similarity ratio. Four main vegetation types were so identified. They were ecologically characterized by an indirect gradient analysis based on correspondence analysis. Furthermore, dynamic c...

Tomaselli, M.; Agostini, N.

1990-01-01

159

Mapping the spectral variability in photosynthetic and non-photosynthetic vegetation, soils, and shade using AVIRIS  

Science.gov (United States)

The primary objective of this research was to map as many spectrally distinct types of green vegetation (GV), non-photosynthetic vegetation (NPV), shade, and soil (endmembers) in an Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) scene as is warranted by the spectral variability of the data. Once determined, a secondary objective was to interpret these endmembers and their abundances spatially and spectrally in an ecological context.

Roberts, Dar A.; Smith, Milton O.; Sabol, Donald E.; Adams, John B.; Ustin, Susan L.

1992-01-01

160

Ocena ranljivosti prsti in vegetacije = Evaluation of the vulnerability of soils and vegetation  

Directory of Open Access Journals (Sweden)

Full Text Available Application of methodologyfor environmental vulnerability studies of two landscape- formingcomponents, soils and natural vegetation, is presented. Evaluation ofenvironmental vulnerability from the view of particular landscape-formingcomponent can be adjusted to different spatial levels: smallerlandscape-ecological units or larger, but still rather homogeneouslandscape-ecological types. With sufficient data it is possible quiteprecisely to evaluate environmental vulnerability on the level of landscapeunits. On the level of landscape-ecological types the generalisation ismuch more significant. Despite this the environmental vulnerability studiesgive usoverview over the state of the environment and the impact of humanpressures.

Barbara Lampi?

2002-01-01

 
 
 
 
161

Nitrogen–use efficiency in different vegetation type at Cikaniki Research Station, Halimun-Salak Mountain National Park, West Java  

Directory of Open Access Journals (Sweden)

Full Text Available A research about nitrogen–use efficiency (NUE and trees identification was conducted at different vegetation type at Cikaniki, Halimun-Salak National Park, West Java. Plot quadrate methods (20 x 50 m was used to analyze trees vegetation and Kjeldahl methods was used to analyze leaf nitrogen. The width and length of the leaf was also measured to obtain the leaf surface area. The result showed that there are 61 individual trees which consisted of 24 species was identified. The species which have 5 highest important value are Altingia excelsa (64,657, Castanopsis javanica (39,698, Platea latifolia (27,684, Garcinia rostrata (21,151, and Schima walichii (16,049. Futhermore Eugenia lineata (13,967, Melanochyla caesa (12,241, Quercus lineata (10,766, platea excelsa (10,766 have lower important value. Other trees have important value less than 10. Morphological and nitrogen content analyze were done on 4 species : Quercus lineata, G. rostrata, A. excelsa, and E. lineata. Among them, Quercus lineata has highest specific leaf area (SLA (0,01153, followed by G. rostrata (0,00821, A. excelsa (0,00579, and E. lineata (0,00984 g/cm2. The highest number of stomata was found on A. excelsa (85,10/mm2, followed by E. lineata (74,40/mm2, Q. lineata (53,70/mm2, and G. rostrata (18,4 /mm2. The emergent species (A. excelsa and Q. lineata have higher nitrogen content than the underlayer species (G. rostrata and E. lineata. A. excelsa have highest nitrogen use efficiency (28,19% compare to E. lineata (23,81% , Q. lineata (19,09%, and G. rostrata (14,87%. Although not significant, emergen species have higher NUE than underlayer species.

SUHARNO

2007-10-01

162

Residuos de plaguicidas organoclorados en 4 tipos de aceites vegetales / Organochlorine pesticide residues in 4 types of vegetable oils.  

Scientific Electronic Library Online (English)

Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish Esta investigación tuvo como objetivos identificar y cuantificar residuos de los plaguicidas organoclorados (POC) hexaclorobenceno (HCB), lindano, cis-clordano, heptacloro, aldrín, dieldrín, endrín y o,p’-diclorodifeniltricloroetano (o,p’-DDT) en aceites de maíz, soya, girasol y mezclas de aceites, [...] que se expenden en la ciudad de Maracaibo, Venezuela. Se analizaron 30 muestras de 4 tipos de aceites de 10 marcas comerciales. La extracción de residuos de POC se realizó según la técnica de la AOAC. Para la identificación y cuantificación se utilizó un cromatógrafo de gases con detector de captura electrónica (GC-ECD), y para la confirmación, un cromatógrafo de gases acoplado a un espectrómetro de masas (GCMS). Todos los residuos de POC investigados fueron detectados en las muestras analizadas. Se detectaron en mayor concentración (mg/ g) aldrín (0,0088), lindano (0,0054) y o,p’-DDT (0,0035). El análisis estadístico demostró diferencias significativas (P Abstract in english The present study had as objectives to identify and to quantify organochlorine pesticide residues (OCP) hexachlorobenzene (HCB), lindane, cis-chlordane, heptachlor, aldrín, dieldrín, endrín and o,p’-DDT in vegetable oils of corn, soybean, sunflower and mixtures of oils, sold in the city of Maracaibo [...] , Venezuela. 30 samples of 4 types of vegetable oils of 10 commercial brands were analyzed. The extraction of OCP residues was done according to the Official Method of AOAC. A gas chromatograph with an electronic capture detector (GC-ECD) was used for identification and quantification of OCP residues and confirmation was done with a gas chromatograph coupled with a mass spectrometer (GC-MS). All the OCP residues investigated were detected in the analyzed samples. Aldrin (0.0088), lindane (0.0054) and o,p’-DDT (0.0035) were the OCP residues detected in higher concentrations (mg/g). The statistical analysis showed significant differences (P

María, Piñero González; Pedro, Izquierdo Córser; María, Allara Cagnasso; Aiza, García Urdaneta.

2007-12-01

163

Does sleep aggravate tension-type headache?: An investigation using computerized ecological momentary assessment and actigraphy  

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Full Text Available Abstract Background Both insufficient sleep and oversleeping have been reported as precipitating and aggravating factors of tension-type headache (TTH. However, previous studies relied on recalled self-reports, and the relationship has not been confirmed prospectively and objectively in a daily life situation. Recently, ecological momentary assessment (EMA using electronic diaries, i.e., computerized EMA, is used to record subjective symptoms with the advantages of avoiding recall bias and faked compliance in daily settings. In addition, actigraphy has become an established method to assess sleep outside laboratories. Therefore, the aim of this study was to investigate the within-individual effect of sleep on the following momentary headache intensity in TTH patients during their daily lives utilizing EMA and actigraphy. Methods Twenty-seven patients with TTH wore watch-type computers as electronic diaries for seven consecutive days and recorded their momentary headache intensity using a visual analog scale of 0-100 approximately every six hours, on waking up, when going to bed, and at the time of headache exacerbations. They also recorded their self-report of sleep quality, hours of sleep and number of awakenings with the computers when they woke up. Physical activity was continuously recorded by an actigraph inside the watch-type computers. Activity data were analyzed by Cole's algorithm to obtain total sleep time, sleep efficiency, sleep latency, wake time after sleep onset and number of awakenings for each night. Multilevel modeling was used to test the effect of each subjective and objective sleep-related variable on momentary headache intensity on the following day. Results Objectively measured total sleep time was significantly positively associated with momentary headache intensity on the following day, while self-reported sleep quality was significantly negatively associated with momentary headache intensity on the following day. Conclusions Using computerized EMA and actigraphy, longer sleep and worse sleep quality were shown to be related to more intense headache intensity on within-individual basis and they may be precipitating or aggravating factors of TTH.

Komaki Gen

2011-08-01

164

Evolutionary Ecology of Human Papillomavirus: Trade-offs, Coexistence, and Origins of High-Risk and Low-Risk Types  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background.?We address the ecological and evolutionary dynamics of human papillomavirus (HPV) that lead to the dichotomy between high-risk (HR) and low-risk (LR) types. We hypothesize that HPV faces an evolutionary tradeoff between persistence and per-contact transmission probability. High virion production enhances transmissibility but also provokes an immune response leading to clearance and limited persistence. Alternatively, low virion production increases persistence at the cost of dim...

Orlando, Paul A.; Gatenby, Robert A.; Giuliano, Anna R.; Brown, Joel S.

2011-01-01

165

[Saturin - effective vegetative remedy in treatment of type 2 diabetes mellitus].  

Science.gov (United States)

A chemical investigation of plant Satureja hortensis L. - garden savory (GS) has been carried out. It is established that the GS is rich in phenolic compounds. Flavonoids apigenin, luteolin, cinaroside, luteolin-glucuronide, luteolin-rutinoside, isoroifolin and phenylcarbonic acids - chlorogenic acid and rosmarinic acid were isolated from the leaves of the plant. The total content of flavonoids and phenylcarbonic acids in GS is 1,6-1,7%. The leaves of GS contain up to 1% essential oil consisting mainly of thymol and methyl carvacrol. Dry aqueous extract of GS leaves, which retains the full range of substances of raw plant material has been obtained. Pharmacological investigation of the GS extract was carried out on intact animals and animals with experimental alloxan diabetes. Antidiabetic Arfasetine was chosen as a reference drug. The study revealed that the GS extract exhibits hypoglycemic activity significantly reducing blood sugar levels and is safe in the long run. Drug dosage form named saturin - capsules containing 0,33 g of dried aqueous extract of GS leaves, has been developed. Clinical trials of Saturin confirmed its effiacy in diabetes mellitus type 2. The drug is registered by the Ministry of Health, Labour and Social Welfare of Georgia (Registration Certificate ?003658) and approved for use in type 2 diabetes either independently or in combination with other hypoglycemic agents. Saturin is manufactured at the Experimental and Production Facility of the Institute of Pharmacochemistry. PMID:22466541

Kemertelidze, E; Sagareishvili, T; Syrov, V; Khushbaktova, Z; Tsutskiridze, L; Kurashvili, R

2012-02-01

166

The soil carbon/nitrogen ratio and moisture affect microbial community structures in alkaline permafrost-affected soils with different vegetation types on the Tibetan plateau.  

Science.gov (United States)

In the Tibetan permafrost region, vegetation types and soil properties have been affected by permafrost degradation, but little is known about the corresponding patterns of their soil microbial communities. Thus, we analyzed the effects of vegetation types and their covariant soil properties on bacterial and fungal community structure and membership and bacterial community-level physiological patterns. Pyrosequencing and Biolog EcoPlates were used to analyze 19 permafrost-affected soil samples from four principal vegetation types: swamp meadow (SM), meadow (M), steppe (S) and desert steppe (DS). Proteobacteria, Acidobacteria, Bacteroidetes and Actinobacteria dominated bacterial communities and the main fungal phyla were Ascomycota, Basidiomycota and Mucoromycotina. The ratios of Proteobacteria/Acidobacteria decreased in the order: SM>M>S>DS, whereas the Ascomycota/Basidiomycota ratios increased. The distributions of carbon and nitrogen cycling bacterial genera detected were related to soil properties. The bacterial communities in SM/M soils degraded amines/amino acids very rapidly, while polymers were degraded rapidly by S/DS communities. UniFrac analysis of bacterial communities detected differences among vegetation types. The fungal UniFrac community patterns of SM differed from the others. Redundancy analysis showed that the carbon/nitrogen ratio had the main effect on bacteria community structures and their diversity in alkaline soil, whereas soil moisture was mainly responsible for structuring fungal communities. Thus, microbial communities and their functioning are probably affected by soil environmental change in response to permafrost degradation. PMID:24463013

Zhang, Xinfang; Xu, Shijian; Li, Changming; Zhao, Lin; Feng, Huyuan; Yue, Guangyang; Ren, Zhengwei; Cheng, Guogdong

2014-01-01

167

Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes  

Directory of Open Access Journals (Sweden)

Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. There still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 72 site-years for 58 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SR MAT, irrespective of the type of ecosystem and biome. This convergence is to be theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SR MAT corrected for a factor related to P/PET. Our finding indicates that it is sufficient to measure SR MAT for obtaining a highly constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution and interannual variation of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatio-temporal resolution of a major component of the global carbon cycle.

M. Bahn

2009-12-01

168

Soil respiration at mean annual temperature predicts annual total across vegetation types and biomes  

Science.gov (United States)

Soil respiration (SR) constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. There still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 72 site-years for 58 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SR MAT), irrespective of the type of ecosystem and biome. This convergence is to be theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10). We further show that for seasonally dry sites where annual precipitation (P) is lower than potential evapotranspiration (PET), annual SR can be predicted from wet season SR MAT corrected for a factor related to P/PET. Our finding indicates that it is sufficient to measure SR MAT for obtaining a highly constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution and interannual variation of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatio-temporal resolution of a major component of the global carbon cycle.

Bahn, M.; Reichstein, M.; Davidson, E. A.; Grünzweig, J.; Jung, M.; Carbone, M. S.; Epron, D.; Misson, L.; Nouvellon, Y.; Roupsard, O.; Savage, K.; Trumbore, S. E.; Gimeno, C.; Curiel Yuste, J.; Tang, J.; Vargas, R.; Janssens, I. A.

2009-12-01

169

Relationship between tourism development and vegetated landscapes in Luya Mountain Nature Reserve, Shanxi, China.  

Science.gov (United States)

The relationship between tourism development and vegetated landscapes is analyzed for the Luya Mountain Nature Reserve (LMNR), Shanxi, China, in this study. Indices such as Sensitive Level (SL), Landscape Importance Value (LIV), information index of biodiversity (H'), Shade-tolerant Species Proportion (SSP), and Tourism Influencing Index (TII) are used to characterize vegetated landscapes, the impact of tourism, and their relationship. Their relationship is studied by Two-Way Indicator Species Analysis (TWINSPAN) and Detrended Correspondence Analysis (DCA). TWINSPAN gives correct and rapid partition to the classification, and DCA ordination shows the changing tendency of all vegetation types based on tourism development. These results reflect the ecological relationship between tourism development and vegetated landscapes. In Luya Mountain Nature Reserve, most plant communities are in good or medium condition, which shows that these vegetated landscapes can support more tourism. However, the occurrence of the bad condition shows that there is a severe contradiction between tourism development and vegetated landscapes. PMID:16027998

Cheng, Zhan-Hong; Zhang, Jin-Tun

2005-09-01

170

On variability of evapotranspiration : the role of surface type and vegetation  

DEFF Research Database (Denmark)

This dissertation is part of the long-term catchment-scale hydrological observatory, HOBE, situated in the Skjern River catchment covering 2500 km2 on the western coast of Denmark. To gain a more detailed knowledge of how evapotranspiration is controlled by the local surface and weather patterns, eddy-covariance systems was installed over the tree dominant surface types in the catchment; an agricultural field, a spruce [Picea abies (L.) H. Karst] plantation and a meadow site. Measurements started in late 2008, and the full evaporation and energy balances for the years 2009-2011 forms the basis for this study. At the spruce plantation additional separate measurements of transpiration, interception evaporation and forest floor evaporation was performed. Transpiration was measured in the growing season of 2010 using Granier type TDP sap flux probes, interception was measured using net precipitation gauges for the years of 2010 and 2011 and forest floor evaporation was measured on a campaign basis by weighing cut out sections for forest floor. The cumulative measured evapotranspiration from the three surfaces showed large differences. 2009 was an unusually dry year with much lower than normal rates of precipitation in April, May and June, while 2010 and 2011 where normal years in terms of precipitation. The meadow site and agricultural site had the largest evapotranspiration in dry year of 2009 at 512 and 470 mm respectively, while the normal years 2010 and 2011 saw 446 and 455 mm for the meadow and 406 and 400 mm for the agricultural site. The spruce plantation showed the opposite pattern. In 2009 the ET was 494 mm while in 2010 and 2011 the sum was 545 and 544 mm respectively. In all years the agricultural site had less evapotranspiration than the natural surfaces. In the dry year 2009 the meadow had slightly more evapotranspiration than spruce plantation, while in the normal years 2010 and 2011 the forest had considerably more evapotranspiration than either the Meadows or the Farm. At the agricultural site, transpiration was the most important component of the evapotranspiration. The rate of evapotranspiration was controlled by crop development and by the available energy. At the meadow site soil evaporation and evaporation from free water surfaces was the most important parts of the evapotranspiration. The rate of evapotranspiration was controlled by the water level in the Skjern River which influenced the ground water level in the meadows and by the available energy. At the spruce plantation transpiration and terception evaporation were both important. The rate of transpiration was heavily influenced by stomatal control in response to high vapor pressure deficits. In addition soil moisture stress had a limiting effect during prolonged dry periods. Interception evaporation was controlled by the amount and duration of precipitation. During rain, advection was found to comprise about half the energy balance of the spruce plantation in summer and the majority the energy balance in winter. On average, 19% of the precipitation evaporated during rain in summer, and 12% of the precipitation evaporated during rain in winter. Canopy structure in the forest were found to affect both transpiration and interception evaporation. Young stands with an open canopy structure transpired at about 30% higher rate than mature stands with a close canopy structure; the young stands had an interception evaporation of 31% of the gross precipitation, while the mature stands had an interception evaporation of 34% of the gross precipitation. Within the mature stands there was an edge effect with trees next to access roads and aisles being responsible for a disproportionally large part of the stand transpiration.

Ringgaard, Rasmus

2012-01-01

171

Some Ecological Aspects of Little Honeybee (Apis florea F. and Type of Sugar Contents in Honey in Northeast Thailand  

Directory of Open Access Journals (Sweden)

Full Text Available This research was carried out at Khon Kaen and Maha Sarakham Provinces in northeastern region of Thailand. The work designed to investigate ecological locations and types of sugar in honey of Little Honeybee (Apis florea F.. The results showed that there were four types of ecological locations found, i.e. cropland and degradation forest, orchard farm, villages, and housing area of government?s official. Five types of sugar contents in honey were found with majority of fructose followed by glucose, lactose, maltose, and least with sucrose. The highest amounts of sugar in honey were highest in June followed by February, December, January, March, September, April, October and November. All types of sugar had no effect on egg rate, worker, and drone cells except fructose where it had highly significant effect on number of queen cells. A range of 1-1.05 (g ml-1 of total sugar had highly significant effect on number of queen cells, but with higher range number of queen cells was declined

Ch. Onlamai

2004-01-01

172

Consequences and feedbacks on CO2 fluxes of climate change impacts on alpine vegetation  

Science.gov (United States)

The vegetation in a high alpine site of the European Alps experienced changes in area between 1953 and 2003 as a result of climate change (Cannone et al. 2007). Shrubs showed rapid expansion rates of 5.6% per decade at altitudes between 2400 m and 2500 m. Above 2500 m, vegetation coverage exhibited unexpected patterns of regression associated with increased precipitation and permafrost degradation. The warming of air temperature induced a cascade effect, with changes in the all ecological series (from the shrubland to the nival snowbed vegetation), with the arrival of the alpine shrubland and upward displacement of the alpine grassland (especially between 2230 and 2500 m). During the growing season 2008 (since the late-spring snowmelt to the start of the continuous snow cover in fall) we analyzed and measured the CO2 fluxes associated to the vegetation types exhibiting the highest changes since 1953 until today. In particular, we monitored two different ecological types of shrubland vegetations (the chionophilous alpine shrubs dominated by Rhododendron ferrugineum and the wind-swept community of dwarf shrubs dominated by Loiseleuria procumbens), the climax alpine grassland (dominated by Carex curvula), the pioneer discontinuous alpine vegetation, the snowbed vegetation (dominated by Salix herbacea) and the barren ground. CO2 fluxes (i.e. net ecosystem exchange, ecosystem photosynthesis and ecosystem respiration), biomass, soil C and N were measured for all these vegetation types. Implications of the changes occurred to the CO2 fluxes above 2200 m a.s.l. in response to the areal changes of spatial distribution of the investigated vegetation types and their potential feedbacks are discussed. Nicoletta Cannone, Sergio Sgorbati, and Mauro Guglielmin 2007. Unexpected impacts of climate change on alpine vegetation. Front Ecol Environ 2007; 5(7): 360-364

Cannone, N.; Guglielmin, M.

2009-04-01

173

Vegetation classification, mapping, and monitoring at Voyageurs National Park, Minnesota: An application of the U.S. National Vegetation Classification  

Science.gov (United States)

Question: How can the U.S. National Vegetation Classification (USNVC) serve as an effective tool for classifying and mapping vegetation, and inform assessments and monitoring? Location: Voyageurs National Park, northern Minnesota, U.S.A and environs. The park contains 54 243 ha of terrestrial habitat in the sub-boreal region of North America. Methods: We classified and mapped the natural vegetation using the USNVC, with 'alliance' and 'association' as base units. We compiled 259 classification plots and 1251 accuracy assessment test plots. Both plot and type ordinations were used to analyse vegetation and environmental patterns. Color infrared aerial photography (1:15840 scale) was used for mapping. Polygons were manually drawn, then transferred into digital form. Classification and mapping products are stored in publicly available databases. Past fire and logging events were used to assess distribution of forest types. Results and Discussion: Ordination and cluster analyses confirmed 49 associations and 42 alliances, with three associations ranked as globally vulnerable to extirpation. Ordination provided a useful summary of vegetation and ecological gradients. Overall map accuracy was 82.4%. Pinus banksiana - Picea mariana forests were less frequent in areas unburned since the 1930s. Conclusion: The USNVC provides a consistent ecological tool for summarizing and mapping vegetation. The products provide a baseline for assessing forests and wetlands, including fire management. The standardized classification and map units provide local to continental perspectives on park resources through linkages to state, provincial, and national classifications in the U.S. and Canada, and to NatureServe's Ecological Systems classification. ?? IAVS; Opulus Press.

Faber-Langendoen, D.; Aaseng, N.; Hop, K.; Lew-Smith, M.; Drake, J.

2007-01-01

174

Pool-Type Fishways: Two Different Morpho-Ecological Cyprinid Species Facing Plunging and Streaming Flows  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Fish are particularly sensitive to connectivity loss as their ability to reach spawning grounds is seriously affected. The most common way to circumvent a barrier to longitudinal connectivity, and to mitigate its impacts, is to implement a fish passage device. However, these structures are often non-effective for species with different morphological and ecological characteristics so there is a need to determine optimum dimensioning values and hydraulic parameters. The aim of this work is to s...

Branco, Paulo; Santos, Jose? M.; Katopodis, Christos; Pinheiro, Anto?nio; Ferreira, Maria T.

2013-01-01

175

The identification of selected vegetation types in Arizona through the photointerpretation of intermediate scale aerial photography. M.S. Thesis  

Science.gov (United States)

The author has identified the following significant results. Nine photography interpretation tests were performed with a total of 19 different interpreters. Three tests were conducted with black and white intermediate scale photography and six tests with color infrared intermediate scale photography. The black and white test results show that the interpretation of vegetation mapped at the association level of classification is reliable for all the classes used at 61%. The color infrared tests indicate that the association level of mapping is unsatisfactory for vegetation interpretation of classes 1 and 6. Students' t-test indicated that intermediate scale black and white photography is significantly better than this particular color infrared photography for the interpretation of southeastern Arizona vegetation mapped at the association level.

Ross, G. F. (principal investigator)

1973-01-01

176

Trophodynamics of current use pesticides and ecological relationships in the Bathurst region vegetation-caribou-wolf food chain of the Canadian Arctic.  

Science.gov (United States)

The bioaccumulation of current use pesticides (CUPs) and stable isotopes of carbon and nitrogen were investigated in vegetation-caribou-wolf food chain in the Bathurst region (Nunavut, Canada). Volumetric bioconcentration factors (BCF(v)) in vegetation were generally greatest for dacthal (10-12)???endosulfan sulfate (10-11)?>?ß-endosulfan (>9.0-9.7)???pentachloronitrobenzene (PCNB; 8.4-9.6)?>??-endosulfan (8.3-9.3)?>?chlorpyrifos (8.0-8.7) >chlorothalonil (7.6-8.3). The BCF(v) values in vegetation were significantly correlated with the logarithm of the octanol-air partition coefficients (log?K(OA)) of CUPs (r(2) ?=?0.90, p?=?0.0040), although dacthal was an outlier and not included in this relationship. Most biomagnification factors (BMFs) for CUPs in caribou:diet comparisons were significantly less than 1. Similarly, the majority of wolf:caribou BMFs were either significantly less than 1 or were not statistically greater than 1. Significant trophic magnification factors (TMFs) were all less than 1, indicating that these CUPs exhibit trophic dilution through this terrestrial food chain. The log K(OA) reasonably predicted bioconcentration in vegetation for most CUPs but was not correlated with BMFs or TMFs in mammals. Our results, along with those of metabolic studies, suggest that mammals actively metabolize these CUPs, limiting their biomagnification potential despite entry into the food chain through effective bioconcentration in vegetation. PMID:24975230

Morris, Adam D; Muir, Derek C G; Solomon, Keith R; Teixeira, Camilla; Duric, Mark; Wang, Xiaowa

2014-09-01

177

Does the endangered Knysna seahorse, Hippocampus capensis, have a preference for aquatic vegetation type, cover or height?  

Directory of Open Access Journals (Sweden)

Full Text Available The Knysna seahorse,Hippocampus capensis, is an endangered teleost confined to three South African estuaries. Its abundance within these systems is low and distributions are patchy. Consequently, monitoring population sizes is labour-intensive. The aim of this study was to establish if Knynsa seahorses are associated with specific regions within the estuaries, on which conservation efforts could concentrate. The relationship of Knysna seahorses with aquatic vegetation was analysed in the Knysna Estuary (the largest of the three estuarine systems inhabited by H. capensis to determine whether this species shows a preference for a particular plant species, vegetation density or vegetation height. Seahorses were associated with five dominant aquatic plants: Zostera capensis, Caulerpa filiformis, Codium extricatum, Halophila ovalis and Ruppia cirrhosa. Together, these comprised 96% of the submerged objects with which seahorses were associated. The relative abundance of plant species changed along the estuary, but seahorses were present throughout the system, except at the estuary mouth, which was characterized by low plant densities and strong currents. No significant difference was found between the proportion of plant species present in a particular region of the estuary and the proportion of plants that seahorses used as holdfasts. However, when Z. capensis and C. filiformis were present at the same sites, adult seahorses preferred C. filiformis as holdfast. Adult seahorse density (individuals/m2 was significantly correlated with percentage vegetation cover and with holdfast length, but juvenile seahorse density was not. Nonetheless, significantly more adult and juvenile seahorses were found at sites characterized by high vegetation cover (>75% than at sites with lower cover. Our results indicate that although there is some evidence that Knynsa seahorses prefer certain plant species over others, they are likely to be encountered anywhere in the estuary where aquatic plants are present. Conservation efforts in the Knysna Estuary should thus concentrate on such vegetated areas, which comprise approximately 11% of the total submerged surface area.

Thomas Hecht

2011-10-01

178

Composição da entomofauna da Floresta Nacional do Araripe em diferentes vegetações e estações do ano / Composition of entomofauna on the Araripe National Forest in different vegetation types and year seasons  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A ocorrência de insetos tem grande significado ecológico e está relacionada com os fatores ambientais, disponibilidade de alimento e abrigo. Para avaliar a composição da entomofauna, em diferentes tipos de vegetação (Cerrado, Carrasco e Mata Úmida) e estações do ano na Floresta Nacional do Araripe, [...] Crato, Ceará, nordeste brasileiro, foram realizadas coletas semanais na estação seca (setembro a dezembro) e chuvosa (abril a julho), por meio de armadilhas McPhail, de solo e bandejas amarelas. Os insetos da ordem Coleoptera são numerosos, na estação seca, agindo como polinizadores, fitófagos e detritívoros, além de decompositores de matéria orgânica, na estação chuvosa. Os Diptera são numerosos na estação chuvosa, quando são encontradas moscas frugívoras, decompositoras de carcaças de animais, de matéria orgânica e predadoras; os da família Calliphoridae predominam no Cerrado; da família Tachinidae, no Carrasco, e da Tephritidae, na Mata Úmida. Os Orthoptera Gryllidae predominam na Mata Úmida e os Hymenoptera Formicidae, no Carrasco e Cerrado na estação seca. Portanto, cada grupo de insetos desempenha um papel ecológico sobre as vegetações, nas diferentes estações do ano. Abstract in english The occurrence of insects has great ecological significance and is related to environmental factors, food availability, and refuge. We assess the composition of the entomofauna in different vegetation types (cerrado, carrasco and humid forest), and seasons in the Araripe National Forest, Crato-CE, b [...] y weekly collections made in the dry season (September to December) and in the rainy season (April to July), through McPhail, pitfall and yellow tray traps. Many Coleoptera occur in the dry season, acting as pollinators, phytophagous, detritivore and decomposers of organic matter in the rainy season. Already, the Diptera is abundant in the rainy season, when fruit flies are found, decomposing animal carcasses, organic matter and predators. The Calliphoridae family predominate in the Cerrado, the Tachinidae in the Carrasco and Tephritidae in the Humid Forest. The Orthoptera Gryllidae predominate in the Humid Forest and the Hymenoptera Formicidae in the Carrasco and Cerrado in the dry season. Therefore, there is a satisfactory balance in the structure and functioning of the Araripe National Forest as each group plays an important ecological role on the vegetation, in the different seasons of the year.

Francisco Roberto de, Azevedo; Maria Andréia Rodrigues de, Moura; Maria Solidade Barbosa, Arrais; Daniel Rodrigues, Nere.

2011-12-01

179

Projected impacts of 21st century climate change on the distribution of potential habitat for vegetation, forest types and major conifer species across Russia.  

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Global simulations have demonstrated the potential for profound effects of GCM-projected climate change on the distribution of terrestrial ecosystems and individual species at all hierarchical levels. We modeled progressions of potential vegetation cover, forest cover and forest types in Russia in the warming climate during the 21st century. We used large-scale bioclimatic models to predict zonal vegetation (RuBCliM), and forest cover (ForCliM) and forest types. A forest type was defined as a combination of a dominant tree conifer and a ground layer. Distributions of vegetation zones (zonobiomes), conifer species and forest types were simulated based on three bioclimatic indices (1) growing degree-days above 5oC ; (2) negative degree-days below 0oC; and (3) an annual moisture index (ratio of growing degree days to annual precipitation). Additionally, the presence/absence of continuous permafrost, identified by active layer depth of 2 m, was explicitly included in the models as limiting the forests and tree species distribution in Siberia. All simulations to predict vegetation change across Russia were run by coupling our bioclimatic models with bioclimatic indices and the permafrost distribution for the baseline period 1971-2000 and for the future decades of 2011-2020, 2041-2050 and 2091-2100. To provide a range of warming we used three global climate models (CGCM3.1, HadCM3 and IPSLCM4) and three climate change scenarios (A1B, A2 and B1). The CGCM model and the B1 scenario projected the smallest temperature increases, and the IPSL model and the A2 scenario projected the greatest temperature increases. We compared the modeled vegetation and the modeled tree species distributions in the contemporary climate to actual vegetation and forest maps using Kappa (K) statistics. RuBioCliM models of Russian zonal vegetation were fairly accurate (K= 0.40). Contemporary major conifer species (Pinus sibirica, Pinus sylvestris, Larix spp., Abies sibirica and Picea obovata) distributions also showed good match with the modeled ranges for the major conifer species from 41% to 78%. Those matches would be higher if only later seral stages were considered, because historically part of the primary conifer forests have been replaced by secondary birch and aspen forests after large disturbances (clearcuts and wildfire). With these projected climates, the zonobiomes would need to shift far to the north in order to reach equilibrium with the change in climate. Under the warmer and drier projected future climate climate, most of Russia would be suitable for the forest-steppe ecotone and grasslands rather than for forests. Water stress tolerant light-needled taiga (Pinus sylvestris and Larix spp.) would have an increased advantage over water-loving dark-needled taiga (Pinus sibica, Abies sibirica, Picea obovata) in a new climate. The permafrost-tolerant L. dahurica taiga would remain the dominant forest type in the many current permafrost areas. Accumulated surface fuel loads due to increased tree mortality from drought, insects and other factors, especially at the southern forest border and in interior Siberia (Yakutia), together with an increase in severe fire weather would also lead to increases in large, high-severity fires, which are expected to facilitate vegetation progression towards equilibrium with the climate.

Tchebakova, Nadezda; Parfenova, Elena; Cantin, Alan; Shvetsov, Eugene; Soja, Amber; Conard, Susane

2013-04-01

180

[Communities of Actynomicetes fungy in three vegetation types of the Colombian Amazon: abundance, morphotypes and the 16s rDNA gene].  

Science.gov (United States)

Among soil microorganisms, Actinomycetes play an important role in the sustainability of natural and agricultural systems: decomposition of organic matter; degradation of recalcitrant compounds like lignin; nitrogen fixation; degradation of agricultural chemicals and biological control in plants and animals. We evaluated their diversity in soils under three different vegetation covers (pasture, tropical primary forest and stubble) at two depths in the Southern Colombian Amazon border. We collected five replicates per vegetation type (in each, three samples at 0-20cm and three at 20-30cm; for a total of 30 samples). Abundance and phenotypic diversity were determined by plate counting. Genomic DNA was extracted from the isolates: the 16s rDNA gene was amplified with specific primers, and its genetic diversity was estimated by means of an amplified restriction analysis (ARDRA). Actynomicetes abundance varied with vegetation and depth, possibly reflecting presence of earthworms, macro-fauna and physico-chemical characteristics associated to fertility, as well as organic matter, total bases, and optimal capacity to cationic interchange. Primary forests had the highest diversity. Sixteen morpho-types (six genera) were identified; Streptomyces was the most abundant everywhere. The heterogeneity ofARDRA patterns prevented species identification because of the intra-species variability in sequences of 16s rDNA operons. This community is a biological indicator of landscape alteration and could include new bio-active compounds of pharmaceutical interest. PMID:20073339

Cardona, Gladys Inés; Peña-Venegas, Clara Patricia; Ruiz-García, Manuel

2009-12-01

 
 
 
 
181

Geophysical Applications of Vegetation Modeling  

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This thesis describes the development and selected applications of a global vegetation model, BIOME4. The model is applied to problems in high-latitude vegetation distribution and climate, trace gas production, and isotope biogeochemistry. It demonstrates how a modeling approach, based on principles of plant physiology and ecology, can be applied to interdisciplinary problems that cannot be adequately addressed by direct observations or experiments. The work is relevant to understanding the p...

Kaplan, J. O.

2001-01-01

182

Dinâmica espaço-temporal (1962-2006) das fitofisionomias em unidade de conservação do Cerrado no sudeste do Brasil / Spatial and temporal dynamics (1962-2006) of Cerrado vegetation types in a protected area, southeastern Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Estudos recentes indicam que em áreas de Cerrado protegidas das atividades antrópicas ocorre uma evolução estrutural de fitofisionomias abertas para outras mais fechadas, com tendência ao desaparecimento das primeiras. Analisou-se a dinâmica das fisionomias do Cerrado ao longo de 44 anos, na Estação [...] Ecológica de Assis, SP, uma das poucas unidades de conservação do bioma no sudeste do Brasil, com o objetivo de caracterizar e quantificar possíveis tranformações fisionômicas no tempo e no espaço. Protegida de pressões antrópicas por longo tempo, observações de campo têm indicado um adensamento da vegetação em toda a área, rumo a um clímax de estrutura florestal. Para realizar este estudo foram utilizadas aerofotos (1962, 1984 e 1994), imagens "QuickBird" (2006) e reconhecimento de campo. Durante o período compreendido por este estudo, a área ocupada pelas fisionomias campestres foi reduzida de 23% para menos de 1% da área estudada, enquanto, no outro extremo do gradiente fisionômico, a proporção correspondente ao cerradão aumentou de 53% para 91%. O ritmo de adensamento da vegetação não foi o mesmo em toda a área, estando, aparentemente, correlacionado com a posição topográfica e diferenças edáficas. Acreditamos que as fisionomias campestres e savânicas inicialmente existentes eram mantidas em decorrência de pressões antrópicas, que impediam a evolução rumo a um clímax edafo-climático de maior fitomassa. Confirmando o que tem sido observado em outros locais, a proteção contra o fogo e a suspensão de atividades agropastoris possibilitaram uma evolução gradativa das formações abertas (campo, campo cerrado e cerrado típico) para outras mais fechadas (cerrado denso e cerradão), tendendo as primeiras ao desaparecimento, caso não ocorram novos distúrbios. As conseqüências dessas transformações, relacionadas com estratégias de manejo, conservação da biodiversidade e fixação de carbono são discutidas. Abstract in english Recent studies indicate that after protection from human pressures (fire, cattle grazing and agriculture), structural changes occur in the cerrado vegetation, changing open physiognomies into more closed savannas. We analyzed the dynamics of vegetation types along 44 years, at Assis Ecological Stati [...] on, one of the rare conservation units protecting the cerrado biome in the southeastern São Paulo State, Brazil, with the aim of characterizing and quantifying those changes in space and time. Protected against human pressures since a long time, field observations have shown an upgrade of local cerrado physiognomies, through a successional process whose structural climax can be a forest physiognomy, with a continuous arboreal stratum. The dynamics of the vegetation types was analyzed by using aerial photographs (1962, 1984 and 1994), Quick Bird satellite images (2006) and field surveys. During this 44 years period, field physiognomies were reduced from 23% to less than 1% of the total area studied. In the other extreme, woodland savanna increased from 53% to 91% of the area. Changes did not happen at the same rhythm across the area, and that is apparently correlated to microclimate and edaphyc differences. We believe that field and savannic physiognomies initially existing were mostly maintained due to heavy human pressures, constraining the secondary succession towards an edapho-climatic climax of greater biomass. Confirming the observations of cerrado areas elsewhere, protection against fire, cattle grazing and agriculture allowed the evolution of open vegetation types into more closed ones, tending to be locally extinct the first if new disturbances do not occur. Consequences of these changes related to management strategies, biodiversity conservation and carbon sink are discussed.

Eduardo Da Silva, Pinheiro; Giselda, Durigan.

2009-09-01

183

Comparison of different types of coatings in headspace solid phase micro extraction for the analysis of pesticide residues in vegetables and fruits  

International Nuclear Information System (INIS)

Despite the continuing development of solid-phase micro extraction (SPME) fiber coatings, their selection presents some difficulties for analytes in choosing the appropriate fiber for a particular application. There are many types of SPME coatings available commercially. The most widely used for determination of pesticide residues in vegetable and fruits are polydimethylsiloxane (PDMS) and polyacrylate (PA). A headspace solid phase micro extraction (HS-SPME) procedure using these two commercialized fibers (PDMS and PA) is presented for the determination of selected groups of organo chlorine and organophosphorus pesticides. The extraction performances of these compounds were compared using these two fibers. The optimal experimental procedures for the adsorption and desorption of pesticides were determined. An explanation for the extraction differences is suggested based on the different thickness, polarity of the polymeric film of fibers and the different extracting matrices. In addition, the higher detector response of the pesticides after addition of aliquots of water and an organic solvent to the vegetable and fruit samples are also discussed. The SPME fibers were reusable until a maximum of 120 extractions. Finally, the optimized procedures were applied successfully for the determination of these compounds in vegetable and fruits samples. Mean recoveries for all pesticides were between 75.0-97 % with RSD below 7 %. (author)

184

Decadal-Scale Vegetation Dynamics of Kolkata and Its Surrounding Areas, India Using Fuzzy Classification Technique  

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Full Text Available Vegetation is an important component of any ecosystem. In urban areas, presence of vegetation is essential for reducing the effects of environmental pollution and maintaining the ecological balance. In the wake of excessive growth of population, the urban vegetation with parkland, especially in developing countries, are diminishing rapidly to provide additional space to various other types of land use. However, such reductions can have serious future implications. Therefore, an assessment of the vegetation cover of urban areas is essential. In this paper, Landsat satellite imageries have been used to study the changes in the vegetation cover of Kolkata, the largest metropolis in eastern India, from 1973 to 2011. The entire area of Kolkata and its surroundings (up to a distance of 10 km has been divided into four quadrants according to the cardinal directions (northeast, southeast, southwest and northwest and six concentric rings of 2 km radius each, and from these 24 sectors (four quadrants and six concentric circles, vegetated lands have been identified for analyzing the changes during the study period. There is a constant decrease of vegetation cover from 1973 till date. The outer periphery of the city is characterized by more urban vegetation as compared to the core of the city. Apart from this, the western sector is denser in terms of vegetation than the eastern one.

Arun Mondal

2012-08-01

185

Diurnal variation of tension-type headache intensity and exacerbation: An investigation using computerized ecological momentary assessment  

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Full Text Available Abstract Backgrounds Tension-type headache is a common psychosomatic disease. However, diurnal variation of headache is yet to be clarified, perhaps due to the lack of an appropriate method to investigate it. Like other painful diseases, it would be helpful to know if there is diurnal variation in tension-type headaches, both for managing headaches and understanding their pathophysiology. The aim of this study was to determine if there is diurnal variation in the intensity and exacerbation of tension-type headache. Methods Patients (N?=?31 with tension-type headache recorded for one week their momentary headache intensity several times a day and their acute headache exacerbations using a watch-type computer as an electronic diary (computerized ecological momentary assessment. Multilevel modeling was used to test the effects of time of day on momentary headache intensity and on the occurrence of acute exacerbations. Results A significant diurnal variation in momentary headache intensity was shown (P?=?0.0005, with the weakest headaches in the morning and a peak in the late afternoon. A between-individual difference in the diurnal pattern was suggested. On-demand medication use was associated with a different diurnal pattern (P?=?0.025, suggesting that headache intensity decreases earlier in the evening in subjects who used on-demand medication, while headache subtype, prophylactic medication use, and sex were not associated with the difference. The occurrence of acute headache exacerbation also showed a significant diurnal variation, with a peak after noon (P?=?0.0015. Conclusions Tension-type headache was shown to have a significant diurnal variation. The relation to pathophysiology and psychosocial aspects needs to be further explored.

Kikuchi Hiroe

2012-09-01

186

Description and validation of an automated methodology for mapping mineralogy, vegetation, and hydrothermal alteration type from ASTER satellite imagery with examples from the San Juan Mountains, Colorado  

Science.gov (United States)

The efficacy of airborne spectroscopic, or "hyperspectral," remote sensing for geoenvironmental watershed evaluations and deposit-scale mapping of exposed mineral deposits has been demonstrated. However, the acquisition, processing, and analysis of such airborne data at regional and national scales can be time and cost prohibitive. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor carried by the NASA Earth Observing System Terra satellite was designed for mineral mapping and the acquired data can be efficiently used to generate uniform mineral maps over very large areas. Multispectral remote sensing data acquired by the ASTER sensor were analyzed to identify and map minerals, mineral groups, hydrothermal alteration types, and vegetation groups in the western San Juan Mountains, Colorado, including the Silverton and Lake City calderas. This mapping was performed in support of multidisciplinary studies involving the predictive modeling of surface water geochemistry at watershed and regional scales. Detailed maps of minerals, vegetation groups, and water were produced from an ASTER scene using spectroscopic, expert system-based analysis techniques which have been previously described. New methodologies are presented for the modeling of hydrothermal alteration type based on the Boolean combination of the detailed mineral maps, and for the entirely automated mapping of alteration types, mineral groups, and green vegetation. Results of these methodologies are compared with the more detailed maps and with previously published mineral mapping results derived from analysis of high-resolution spectroscopic data acquired by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) sensor. Such comparisons are also presented for other mineralized and (or) altered areas including the Goldfield and Cuprite mining districts, Nevada and the central Marysvale volcanic field, Wah Wah Mountains, and San Francisco Mountains, Utah. The automated mineral group mapping products described in this study are ideal for application to mineral resource and mineral-environmental assessments at regional and national scales.

Rockwell, Barnaby W.

2012-01-01

187

Establishment of experimental catchments to quantify water use by different vegetation types / Estabelecimento de microbacias experimentais para quantificar uso de água por diferentes tipos de vegetação  

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Full Text Available AbstractThis paper describes the procedure developed to select representative experimental catchments to quantify water use and water use efficiency of different vegetation types. We combined freely available information such as LANDSAT satellite images, digital elevation model, Google Earth images, streamflow and rainfall historical data, and soils and vegetation data to select the experimental catchments. Once these catchments were indentified, sub-catchments with different vegetation were delineated, which were used to define the distribution and installation of the instrumentation. Forty eight catchments and respective sub-catchments of Tasmania in Australia were analyzed and only two catchments were identified as ideal for the purposes of quantifying and comparing the historic and current water use by Eucalyptus plantation, native forest and pasture. We choose one catchment and created four experimental and instrumented sub-catchments with the following predominant land use: Eucalyptus nitens, native forest and pasture. ResumoO presente artigo descreve o procedimento desenvolvido para selecionar microbacias representativas para quantificar o uso de água e a eficiência do uso de água de diferentes tipos de vegetação. Foram combinadas informações disponíveis sem custo tais como: imagens de satélite LANDSAT, modelo digital do terreno, imagens de Google Earth, escoamento superficial e dados históricos de precipitação pluviométrica, tipos de solos e cobertura vegetal para a seleção de microbacias experimentais. Uma vez identificadas as microbacias, sub-microbacias com diferente tipos de vegetação foram delineadas, as quais foram usadas para definir a distribuição e instalação de instrumentação. Foram analisadas quarenta e oito microbacias e respectivas sub-microbacias na Tasmânia na Austrália e somente duas microbacias foram identificadas como ideais para o propósito de quantificar e comparar o histórico e atual uso de água por plantações de eucalipto, floresta nativa e pastagem. Ao final foi escolhida uma microbacia e quatro sub-microbacias experimentais instrumentadas com o uso de solo predominantemente de Eucalyptus nitens, floresta nativa e pastagem.

Almeida Auro Campi

2010-10-01

188

Diversidad de reptiles en tres tipos de vegetación del estado de Hidalgo, México Diversity of reptiles in three vegetation types of the Hidalgo state, México  

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Full Text Available La zona sureste del estado de Hidalgo presenta diversos tipos de vegetación, como el bosque mesófilo de montaña, bosque de pino-encino y bosque de pino, con alta riqueza de reptiles. En este estudio, se analizó la diversidad alfa y beta de los reptiles en los 3 tipos de vegetación presentes en la zona sureste. Durante el periodo de recolección, de junio 2008 a agosto del 2009, se realizaron 12 salidas, 1 por mes, con duración de 3 días cada una. La diversidad de reptiles está compuesta por 25 especies, incluyendo un registro nuevo para el estado, la culebra Thamnophis scaliger. El bosque mesófilo de montaña (BMM presentó la mayor riqueza, con 15 especies, seguido del bosque de pino (BP, con 13, y el bosque de pino-encino (BPE, con 12. Las asociaciones realizadas entre el BMM-BP y BMM-BPE presentaron la más alta disimilitud en especies, y el menor valor fue para el BPE-BP. Este estudio muestra la riqueza y distribución de las especies de los reptiles en los diferentes tipos de vegetación del sureste del estado y presenta nuevos registros de especies para la entidad. El conocimiento de la riqueza de especies por tipos de vegetación de este estudio sienta las bases sobre la biodiversidad, lo que ayuda a plantear estudios dirigidos a la conservación de este grupo.The southeast of Hidalgo in Mexico includes various vegetation types, such as cloud forest, pine-oak forest and pine forest, all harbouring a high species richness of reptiles. In this study we analyzed the alpha and beta diversity of reptiles in 3 vegetation types in the southeast of the state. The field work period was from June 2008 to August 2009, comprising 12 sampling periods of 3 days, 1 per month. The diversity of reptiles is composed of 25 species, reporting the snake Thamnophis scaliger as a new record for the state. The cloud forest (CF has the highest richness, with 15 species, followed by pine forest (PF, with 13, and finally, the pine-oak forest (POF, with 12 species. The associations between the CF-PF and CF-POF showed the highest dissimilarity in species, and the lowest the POF-PF. This study shows the richness and distribution species of the reptiles in the different vegetation types from southeast of the state, presents new records of species from the state and provides the basis for future studies on the biology of some species of reptiles in the area. The knowledge of species richness by vegetation types from this study provides the basis on the biodiversity that help to raise studies directed to the conservation of this group.

Raciel Cruz-Elizalde

2012-06-01

189

Soil, Vegetation, and Seed Bank of a Sonoran Desert Ecosystem Along an Exotic Plant ( Pennisetum ciliare) Treatment Gradient  

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Ecological conditions following removal of exotic plants are a key part of comprehensive environmental management strategies to combat exotic plant invasions. We examined ecological conditions following removal of the management-priority buffelgrass ( Pennisetum ciliare) in Saguaro National Park of the North American Sonoran Desert. We assessed soil, vegetation, and soil seed banks on seven buffelgrass site types: five different frequencies of buffelgrass herbicide plus hand removal treatments (ranging from 5 years of annual treatment to a single year of treatment), untreated sites, and non-invaded sites, with three replicates for each of the seven site types. The 22 measured soil properties (e.g., pH) differed little among sites. Regarding vegetation, buffelgrass cover was low (?1 % median cover), or absent, across all treated sites but was high (10-70 %) in untreated sites. Native vegetation cover, diversity, and composition were indistinguishable across site types. Species composition was dominated by native species (>93 % relative cover) across all sites except untreated buffelgrass sites. Most (38 species, 93 %) of the 41 species detected in soil seed banks were native, and native seed density did not differ significantly across sites. Results suggest that: (1) buffelgrass cover was minimal across treated sites; (2) aside from high buffelgrass cover in untreated sites, ecological conditions were largely indistinguishable across sites; (3) soil seed banks harbored ?12 species that were frequent in the aboveground vegetation; and (4) native species dominated post-treatment vegetation composition, and removing buffelgrass did not result in replacement by other exotic species.

Abella, Scott R.; Chiquoine, Lindsay P.; Backer, Dana M.

2013-10-01

190

Effects of fertilization on the vascular ground vegetation of European beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Lieb.) stands  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of this study was to assess the effects of base cation (Ca, Mg, K) and phosphorous (P) fertilization on the vascular ground vegetation in mature European beech and sessile oak stands located on acid brown soils. Two types of treatment were applied next to control plots (dolomite lime, dolomite lime + natural phosphate + potassium sulphate). Specific richness, total cover (% ), equitability coefficient as well as the Ecological Group of the ground vegetation were studied. Four ye...

Misson, Laurent; Gaëtan du Bus de Warnaffe,; Jonard, Mathieu

2001-01-01

191

To what extent did changes in July temperature influence Lateglacial vegetation patterns in NW Europe?  

Science.gov (United States)

What was the impact of July temperature changes on vegetation patterns during the Lateglacial period in north-west Europe? Chironomid-inferred mean July air temperature estimates (C-Tjul) are proxy temperature records independent of terrestrial vegetation. The relationships between Lateglacial vegetation inferred from pollen percentages and these temperature estimates are explored using data synthesised geographically from 15 sites where both pollen percentages and C-Tjul are published to assess the influence of temperature and of temperature changes on regional vegetation. Direct impacts of temperature on a species involve passing the range limits or realised niche of that species. The Bølling warming allowed vegetation to develop. The Younger Dryas cooling had direct impacts on species and vegetation types that were at a critical ecotone and thus sensitive to change. Precipitation is extremely important and its interaction with temperature controlled most of the vegetation patterns inferred from these NW European pollen data. High precipitation was important in W Norway, whereas aridity in the YD was a controlling factor in N Norway, the Netherlands, and NE Germany. Under constant climate, ecological processes occurred such as immigration, succession, and soil development that resulted in vegetation changes. Biotic interactions were also important, such as the impact of grazing by mega-herbivores during Allerød time in Ireland that may have restricted the development of birch woodland. At the coarse scale of this synthesis, July temperature alone is seen not to be a good predictor of the patterns of pollen percentages and hence of vegetation through the Lateglacial. Rather, it is the interactions of temperature and precipitation, combined with ecological processes that appear to be the major factors influencing Lateglacial palynological and vegetation patterns in NW Europe.

Birks, Hilary H.; Birks, H. John B.

2014-12-01

192

Decreased surface albedo driven by denser vegetation on the Tibetan Plateau  

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The Tibetan Plateau (TP) has fundamental ecological and environmental significance to China and Asia through its influence on regional and continental climates. In recent years, climate warming has caused unprecedented changes to land surface processes on the TP, which would unavoidably undermine the ecological and environmental functions of the TP. Among the numerous land surface processes potentially impacted by climate warming, the effect of vegetation greenness on surface energy balance is one of the most critical, but has been long ignored. In this study, we investigated the spatial and temporal patterns of land surface albedo (LSA) on the TP and evaluated the vegetation greenness in relation to patterns of LSA. We found that LSA has been decreasing in most of the vegetated grasslands on the TP from 2000 to 2013, as compared to a flat trend for desert area. The regions where LSA has been decreasing were spatially correlated to areas of increased vegetation greenness. Along rising altitude, LSA decreasing rate exhibited an overall decreasing trend. Across the TP, elevated vegetation greenness in grasslands acted as a primary factor pulling down LSA. The driving effects of vegetation greenness on LSA vary with grassland types, as revealed by a more significant relationship between vegetation greenness and LSA for the sparsely vegetated zone (i.e. steppe) than the more densely vegetated zone (i.e. meadow). Furthermore, the driving effect of vegetation greenness on LSA exhibited an obvious dependence on altitude as effects with rising altitude were relatively strong up to 3000 m, then weakened from 3500 m to 5000 m, and then the effects again increased from 5000 to 6000 m. The growing season LSA trend revealed in this study emphasizes the need to give greater attention to the growing season LSA flux in future surface energy balance studies.

Tian, Li; Zhang, Yangjian; Zhu, Juntao

2014-10-01

193

MAP OF ECOLOGICAL UNITS IN ROMANIA  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ecological units were delineated based on the ensemble of life conditions whose variety is defined by the specific association of various conditions of climate, relief and lithology, hydrology, vegetable formations and soils, including also the anthropic influence. In the Romania territory 20 ecoregions were delineated, hierarchically grouped in 10 ecological domains and 4 ecological subzones belonging to 2 ecological zones (cold temperate and temperate). Each ecological regions (ecoregio...

Florea, N.

2005-01-01

194

Dynamic monitoring of landscape patterns and ecological processes using HJ-1 and SPOT satellite data over Hulunbeier grassland, China  

Science.gov (United States)

Landscape patterns and ecological processes have been in long-term research focus in the field of landscape ecology, but how to measure their quantitative relations is still open. This work chooses the Hulunbeier grassland as the study area where ecosystem shows high vulnerability, frequent evolvement of landscape patterns and ecological processes. With remote sensing technology, the relationships between landscape patterns and ecological processes were analyzed quantitatively from multi-scale, multi-temporal and time series perspective. Firstly, the information about the current situation and change of landscape patterns and ecological processes are obtained from HJ-1 (Environmental and Disaster Small Satellite) and LANDSAT TM (Thermal Mapper) data. Secondly, SPOT NDVI (Normalized Difference Vegetation Index) data during 2000-2008 are used to analyze the dynamic changes of ecological processes, and to simulate its inter-annual variety at pixel scale. Finally, the dynamic change trends of ecological processes of grassland vegetation are described. The results indicate that the unchanged ecosystem types account for most of the study area, unused land in the central part expands continuously which results in the increase of desertification, and most ecosystem types in the eastern part are changed to grassland and woodland. Furthermore, the vegetation vulnerability is the highest in the grassland-dominated region, the second in grassland-farmland-woodland transition, and the smallest in the woodland-dominated region, where the stability is enhanced in turn. Due to the dynamic change of vegetation, it can be concluded that the study area underwent ecological processes of vegetation cover with a negative trend and a changed phenology.

Zhang, Feng; Li, Ying; Liu, Sihan; Zhao, Shaohua; Wu, Yanting

2014-03-01

195

Vegetation type and the presence of ash as factors in the evolution of soil water repellency after a forest fire  

Directory of Open Access Journals (Sweden)

Full Text Available After wildfires, burning may induce the occurrence of soil water repellency. Soil water repellency may vary in space and time in function of vegetation, the presence of ash and soil moisture. This study analyzes the evolution of fire-induced soil water repellency in function of these factors, and proposes measures to promote the restoration of fire-affected soils. Burnt and unburnt (control soil plots under pine and shrub from a recently burned area (Gorga, Alicante, SE Spain were established. Three treatments were applied: in some of the plots, the original ash layer was kept on the ground; in a second group, the ash layer was removed for simulating the effects of erosion; finally, in a third group, percolating irrigation was conducted to simulate a possible good input of water into the soil profile after burning, that could occur if the first rains were with high quantity but low intensity. During the dry season, soil moisture content was significantly lower in burned plots due to fire-induced water repellency and reduced vegetation cover. During the wet season, soil moisture decreased in the control unburnt plots due to direct evaporation of water intercepted by vegetation and consumption by roots. Fire increased soil water repellency only in plots under pine. Water repellency decreased during the wet season, disappearing in January and reappearing after declining rainfalls. This baseline recovery of soil water repellency was lower where ash removal was simulated. In unburned plots, seasonal fluctuations were less important. In general, ash removal promotes a rapid reduction of water repellency, since it can induce washing of hydrophobic compounds. Irrigation performed immediately after the fire also contributed to decreased water repellency.

P. Jiménez-Pinilla

2013-05-01

196

Effects of soil type and farm management on soil ecological functional genes and microbial activities  

Energy Technology Data Exchange (ETDEWEB)

Relationships between soil microbial diversity and soil function are the subject of much debate. Process-level analyses have shown that microbial function varies with soil type and responds to soil management. However, such measurements cannot determine the role of community structure and diversity in soil function. The goal of this study was to investigate the role of gene frequency and diversity, measured by microarray analysis, on soil processes. The study was conducted in an agro-ecosystem characterized by contrasting management practices and soil types. Eight pairs of adjacent commercial organic and conventional strawberry fields were matched for soil type, strawberry variety, and all other environmental conditions. Soil physical, chemical and biological analyses were conducted including functional gene microarrays (FGA). Soil physical and chemical characteristics were primarily determined by soil textural type (coarse vs fine-textured), but biological and FGA measures were more influenced by management (organic vs conventional). Organically managed soils consistently showed greater functional activity as well as FGA signal intensity (SI) and diversity. Overall FGA SI and diversity were correlated to total soil microbial biomass. Functional gene group SI and/or diversity were correlated to related soil chemical and biological measures such as microbial biomass, cellulose, dehydrogenase, ammonium and sulfur. Management was the dominant determinant of soil biology as measured by microbial gene frequency and diversity, which paralleled measured microbial processes.

Reeve, Jennifer [Washington State University; Schadt, Christopher Warren [ORNL; Carpenter-Boggs, Lynne [Washington State University; Kang, S. [University of Oklahoma; Zhou, Jizhong [University of Oklahoma, Norman; Reganold, John P. [Washington State University

2010-01-01

197

Agro-ecological conditions and morphoproductive properties of spelt wheat  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Experiments were conducted during 2011-2012, at three localities in Serbia (Valjevo, Nova Varoš and Nova Pazova). The seed of spelt wheat cultivar Nirvana was used, having been selected at the Institute of Field and Vegetable Crops in Novi Sad. The objective of the research was to assess the effect of agro-ecological conditions on morphological and productive properties of spelt wheat grown on different types of soils. The effect of the locality was signif...

Jankovi? S.; Ikanovi? J.; Popovi? V.; Raki? S.; Kuzevski J.

2013-01-01

198

Influence of the type of vegetable oil on the drug release profile from lipid-core nanocapsules and in vivo genotoxicity study.  

Science.gov (United States)

The use of rice bran (RB), soybean (SB) or sunflower seed (SF) oils to prepare lipid-core nanocapsules (LNCs) as controlled drug delivery systems was investigated. LNCs were prepared by interfacial deposition using the preformed polymer method. All formulations showed negative zeta potential and adequate nanotechnological characteristics (particle size 220-230? nm, polydispersity index < 0.20). The environmental safety was evaluated through an in vivo protocol (Allium cepa test) and LNCs containing RB, SB or SF oils did not present genotoxic potential. Clobetasol propionate (CP) was selected as a model drug to evaluate the influence of the type of vegetable oil on the control of the drug release from LNCs. Biphasic drug release profiles were observed for all formulations. After 168? h, the concentration of drug released from the formulation containing SF oil was lower (0.36 ?mg/mL) than from formulations containing SB (0.40? mg/mL) or RB oil (0.45 ?mg/mL). Good correlations between the consistency indices for the LNC cores and the burst and sustained drug release rate constants were obtained. Therefore, the type of the vegetal oil was shown as an important factor governing the control of drug release from LNCs. PMID:23978050

Rigo, Lucas Almeida; Frescura, Viviane; Fiel, Luana; Coradini, Karine; Ourique, Aline Ferreira; Emanuelli, Tatiana; Quatrin, Andréia; Tedesco, Solange; Silva, Cristiane B da; Guterres, Silvia Staniçuaski; Pohlmann, Adriana Raffin; Beck, Ruy Carlos Ruver

2014-11-01

199

Climate Change Impacts on Turkish Vegetation  

Science.gov (United States)

The Mediterranean has been identified as a potentially vulnerable hotspot under climate change. In Turkey, climate change projections consistently predict large temperature rises over the 21st century. With 9% of GDP and 25% of employment coming from agriculture, climate change has the potential to significantly affect both the Turkish economy and living standards. Relatively little work has been undertaken to estimate the effects and risks of climate change in Turkey, and many European studies cover do not include the whole of Turkey in their domain and so are of limited use for policy-makers. The Dynamic Global Vegetation Model LPJ-GUESS was parametrised to represent Turkish vegetation. Climate forcings were derived by interpolating meteorological data from over 600 stations from 1975-2010 to a 1km resolution. Soil depth and soil texture data from field measurements were also interpolated to a 1km grid. The model was benchmarked against vegetation type and remotely sensed biomass and tree cover data. Future climate conditions were calculated using the outputs from a set of regional model simulations. In particular the HadRM3P regional climate model was used to downscale five members of a perturbed physics ensemble of global climate projections obtained using HadCM3 general circulation model and the SRES A1B scenario. A delta change factor approach was then used in conjunction with the observed climate data to assess the impact on vegetation structure and ecological processes to the year 2100 using LPJ-GUESS. The resulting changes to productivity, vegetation structure and hydrology are discussed. Eventually these results will be combined with complementary studies concerning wildfire and erosion to produce a risk map for informing policy-makers.

Forrest, Matthew; Dönmez, Cenk; Çilek, Ahmet; Akif Erdogan, Mehmet; Buontempo, Carlo; Hickler, Thomas

2014-05-01

200

The present flora and vegetation of the moraines of the Klutlan Glacier, Yukon Territory, Canada: A study in plant succession*1  

Science.gov (United States)

The flora and vegetation of six ice-cored moraines of the Klutlan Glacier were analyzed in 65 plots by European plant-sociological techniques. The age of each plot was estimated from annual growth rings of shrubs or trees in the plots. Nine major vegetation types are distinguished: Crepis nana, Dryas drummondii, Hedysarum mackenzii, Hedysarum-Salix, Salix-Shepherdia canadensis, Picea-Salix, Picea-Arctostaphylos, Picea-Ledum, and Picea-Rhytidium. These contain plants aged 2-6, 9-23, 10-20, 24-30, 32-58, 58-80, 96-178, 177-240, and >163- >339 yr, respectively. Six other vegetation types are described from windthrow areas, drainage channels, volcanic tephra slopes, lake margins, fens, and drained lakes. The major vegetation types reflect a vegetational succession related to moraine age and stability, with the Crepis nana type as the pioneer vegetation developing through the other vegetation types to the Picea-Rhytidium type on the oldest moraines. Changes in species diversity and soil development, particularly humus accumulation, parallel the vegetational succession. This succession differs from patterns of revegetation of deglaciated landscapes in Alaska and British Columbia today and in Minnesota in late-Wisconsin times because of differences in climate, plant migration, and local ecology.

Birks, H. J. B.

1980-07-01

 
 
 
 
201

Riparian Vegetation Mapping Along the Hanford Reach  

Energy Technology Data Exchange (ETDEWEB)

During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY2002 to support development of a complete data layer describing riparian vegetation cover types on the Columbia River adjacent to the Hanford Site boundaries. Included with this report are the preliminary riparian vegetation maps and the associated metadata for that GIS layer.

FOGWELL, T.W.

2003-07-11

202

Riparian Vegetation Mapping Along the Hanford Reach  

International Nuclear Information System (INIS)

During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealongiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY2002 to support development of a complete data layer describing riparian vegetation cover types on the Columbia River adjacent to the Hanford Site boundaries. Included with this report are the preliminary riparian vegetation maps and the associated metadata for that GIS layer

203

Water deficit affects wood vessels of Croton floribundus Spreng. in different vegetation types, São Paulo State, Brazil / Déficit hídrico interfere nos vasos do lenho de Croton floribundus Spreng. em diferentes tipos de vegetação, SP, Brasil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O déficit hídrico influenciou na formação dos vasos da madeira de Croton floribundus ocorrentes em cinco áreas com as seguintes vegetações: Floresta Ombrófila, Floresta Estacional Semidecidual e Cerradão. As variações dos vasos devem-se especialmente ao déficit hídrico e número de meses com déficit [...] hídrico. Vasos de maior diâmetro ocorreram em áreas com maior déficit hídrico, o que pode indicar uma estratégia para otimizar o transporte de água em épocas favoráveis. Vasos com menores diâmetros ocorreram em áreas com menor déficit hídrico, possivelmente influenciados pelas menores temperaturas mínimas e a ocorrência de geadas, que semelhante a seca, causa a embolia dos vasos. Na Estação Ecológica de Caetetus, Floresta Estacional Semidecidual (área com maior déficit de água) observaram-se investimentos em eficiência e segurança, com a ocorrência de vasos de maior diâmetro associados a um dos menores índices de vulnerabilidade e maior proporção de vasos múltiplos de quatro ou mais elementos. Abstract in english In this paper we showed that water deficit affects the wood vessels of Croton floribundus in five areas with different vegetation types: Rain Forest, Semi-deciduous Forest and Woody Savanna. We concluded that variations in the vessels are due especially to water deficit and the number of months with [...] water deficit. Larger diameter vessels occurred in areas with higher water deficit, which may represent a strategy to optimize the water transport in favorable periods. Vessels with smaller diameters occur in areas with lower deficit, which may be related to lower minimum temperatures and frost occurrence, which like drought can cause vessel embolism. In Caetetus Ecological Station, a Semi-deciduous Forest (area of highest water deficit), we observed investments in efficiency and safety, with the occurrence of larger diameter vessels associated with one of the lowest vulnerability indexes and highest proportions of multiple vessels of four or more elements.

Eduardo Luiz, Longui; Diego, Romeiro; Luana Naves, Testoni; Osny Tadeu de, Aguiar; Roque, Cielo Filho; Israel Luiz de, Lima; Sandra Monteiro Borges, Florsheim.

2012-03-01

204

An ecological type nonlinear model for the removal of carbon dioxide from the atmosphere by introducing liquid species  

Directory of Open Access Journals (Sweden)

Full Text Available The average temperature of our planet is increasing in past several decades due to emission of global warming gases such as CO2, CH4, etc. in the atmosphere leading to undesirable environmental consequences. Therefore, it is necessary to find a mechanism by which a global warming gas can be removed from the regional atmosphere. In this paper, therefore, we proposed an ecological type nonlinear mathematical model for the removal of a global warming gas CO2 from the regional atmosphere by externally introduced liquid species, which may react with this gas and removed it by gravity. The model consists of three dependent variables namely; the concentration of carbon dioxide, the concentration of externally introduced liquid species and the concentration of particulate matters (secondary species formed due to interaction of carbon dioxide with liquid species. The local and global stability conditions are discussed using Routh-Hurwitz criteria and suitable Lyapunove's function respectively. It is shown, analytically and numerically, that the concentration of carbon dioxide decreases as the rate of introduction of externally introduced liquid species increases.

Shyam Sundar

2013-06-01

205

Response of Coprophagus Beetles (Coleoptera: Scarabaeidae on changes of vegetation structure in various habitat types at Lore Lindu National Park, Central Sulawesi  

Directory of Open Access Journals (Sweden)

Full Text Available This study analysed the response of dung beetles ? a group of beetles which play a major role in decomposition of dung and animal carcasses ? to changes of vegetation structure due to forest conversion to different human-made habitat types at the margin of Lore Lindu National Park. Therefore, dung beetles were sampled at natural forest, cacao agroforestry systems and open area. A total of 28 species of coprophagus beetle species were recorded from the sampled sites. Species richness and abundance of dung beetles, particularly of large species, decreased from forest towards agroforestry systems and open areas. However, more than 80 % of the species recorded in natural forest were found in cacao agroforestry systems Of the measured habitat parameters, particularly the number of tree species, air temperature, and canopy cover had a significant power for explaining changes in dung beetle ensembles along the gradient of land-use intensity.

CHRISTIAN H. SCHULZE

2007-01-01

206

The South African National Vegetation Database: History, development, applications, problems and future  

Directory of Open Access Journals (Sweden)

Full Text Available Southern Africa has been recognised as one of the most interesting and important areas of the world from an ecological and evolutionary point of view. The establishment and development of the National Vegetation Database (NVD of South Africa enabled South Africa to contribute to environmental planning and conservation management in this floristically unique region. In this paper, we aim to provide an update on the development of the NVD since it was last described, near its inception, more than a decade ago. The NVD was developed using the Turboveg software environment, and currently comprises 46 697 vegetation plots (relevés sharing 11 690 plant taxa and containing 968 943 species occurrence records. The NVD was primarily founded to serve vegetation classification and mapping goals but soon became recognised as an important tool in conservation assessment and target setting. The NVD has directly helped produce the National Vegetation Map, National Forest Type Classification, South African National Biodiversity Assessment and Forest Type Conservation Assessment. With further development of the NVD and more consistent handling of the legacy data (old data sets, the current limitations regarding certain types of application of the data should be significantly reduced. However, the use of the current NVD in multidisciplinary research has certainly not been fully explored. With the availability of new pools of well-trained vegetation surveyors, the NVD will continue to be purpose driven and serve the needs of biological survey in pursuit of sustainable use of the vegetation and flora resources of the southern African subcontinent.

Leslie W. Powrie

2012-01-01

207

Mapping vegetation communities in Ozark National Scenic Riverways: final technical report to the National Park Service  

Science.gov (United States)

Vegetation communities were mapped at two levels in Ozark National Scenic Riverways (ONSR) usign a hybrid combination of statistical methods and photointerpretation. The primary map includes 49 cover classes, including 24 cleasses that relate to vegetation associations currenly described by the United States National Vegetation Classification Standard (USNVC: The Nature Conservancy, 1994a). The remaining types include cultural features, ruderal communities on abandoned agricultural lands, and non-vegetated classes. Overall map classification accuarcy is 63 percent. The secondary mapping level aggregates communities with similar appearance and ecologically related associations into Community Types. The resultant 33-class Community Type map has an overall classification accuracy of 77 percent and identified groups of communities based on resource management goals within the park. Important additional products include 1) a general probability map for all vegetation associations, which can be used to assess final classification certainty, and 2) individual probability maps for each association, which can be used to identify areas that have a high likelihood of supporting a given type, beyond where that type was identified in the final map products. Other secondary map products include data layers derived from primary color-infrared imagery, secondary imagery data and digital elevation models. A field key and photo guide to associations and complete community descriptions were produced, along with a photo guide of fuel conditions. Wildland fuels data were used to generate a fuels map based upon Anderson's fuels models (1982).

Chastain, Robert A.; Struckhoff, Matthew A.; Grabner, Keith W.; Stroh, Esther D.; He, Hong; Larsen, David R.; Nigh, Timothy A.; Drake, Jim

2006-01-01

208

Macrofossil evidence for pre-settlement vegetation of Central Otago's basin floors and gorges  

International Nuclear Information System (INIS)

Composition of pre-settlement vegetation communities in the semi-arid Central Otago lowlands has been one of New Zealand's long-standing ecological puzzles. Uncertainty is due largely to a paucity of fossil data. Here, we provide new evidence for pre-settlement vegetation in the region based on analyses of plant macrofossils from 15 late Pleistocene and Holocene lowland sites. The assemblages represent two habitat types: wooded or partially wooded intermontane basin-floor wetlands, and low forest and/or shrubland habitats in the Kawarau and Clutha River gorges. In both habitat types, plant communities appear to have been predominantly woody, with significant components of herbaceous dicotyledons but few grasses. Both habitats seem to have undergone major post-settlement vegetation transformation. Several presently common taxa were rare or absent before human settlement, but others (including threatened spring annuals), now rare or extinct in the region, were formerly more common. (author). 57 refs., 5 figs., 3 tabs

209

Seasonal variation and controlling factors of soil carbon effluxes in six vegetation types in southeast of Sweden  

Energy Technology Data Exchange (ETDEWEB)

Soil carbon effluxes of a pine stand, a spruce stand, a lichen rock, two oak stands and a meadow in the Laxemar investigation area in south-eastern Sweden (57 deg 5 N, 16 deg 7 E) have been measured with the closed chamber technique at 14 occasions between 23 of March 2004 and 10th of March 2005. Soil temperature at 10 cm depth, air temperature, soil moisture and photosynthetically active radiation (PAR) were also measured. Exponential regressions with soil respiration against air and soil temperature were used to estimate soil respiration between 15th of March 2004 and 14th of March 2005. A light response curve with Gross Primary Production (GPP) against PAR and a cubic regression with GPP against air temperature were used for modelling GPP in meadow for the growing season, 15th of March to 31st of October 2004. The exponential regressions with soil respiration against air and soil temperature explained on average 30.6% and 47.6% of the variation, respectively. Soil moisture had a linear limiting effect on soil respiration for all ecosystems but spruce, where soil moisture was the limiting factor above a threshold value of about 50%vol. In the forest ecosystems, GPP of the ground vegetation were not reducing soil carbon effluxes, while in meadow it was. In meadow, the light response curve with GPP against PAR explained 32.7% of the variation in GPP while the cubic regression against air temperature explained 33.9%. No significant effect of soil moisture on GPP was detected. The exponential regression equations with air and soil temperature against soil respiration could be used to temporally extrapolate the occasional field measurements. The light response curve with GPP against PAR and the cubic regression with GPP against air temperature could also be used for temporal extrapolation. From the modelled soil respiration, annual soil respiration for the ecosystems in Laxemar, during 15th of March 2004 to 14th of March 2005, were estimated to be between 0.56 and 1.18 kg C/m2/y. Annual GPP of meadow was estimated to be between 0.49 and 0.54 kg C/m2/y, which gives a net ecosystem exchange for the meadow of between 0.38 and 0.66 kg C/m2/y, i.e. a significant loss of carbon to the atmosphere

Tagesson, Torbern (Dept. of Physical Geography and Ecosystem Analysis, Lund Univ., Lund (SE))

2007-11-15

210

Seasonal variation and controlling factors of soil carbon effluxes in six vegetation types in southeast of Sweden  

International Nuclear Information System (INIS)

Soil carbon effluxes of a pine stand, a spruce stand, a lichen rock, two oak stands and a meadow in the Laxemar investigation area in south-eastern Sweden (57 deg 5 N, 16 deg 7 E) have been measured with the closed chamber technique at 14 occasions between 23 of March 2004 and 10th of March 2005. Soil temperature at 10 cm depth, air temperature, soil moisture and photosynthetically active radiation (PAR) were also measured. Exponential regressions with soil respiration against air and soil temperature were used to estimate soil respiration between 15th of March 2004 and 14th of March 2005. A light response curve with Gross Primary Production (GPP) against PAR and a cubic regression with GPP against air temperature were used for modelling GPP in meadow for the growing season, 15th of March to 31st of October 2004. The exponential regressions with soil respiration against air and soil temperature explained on average 30.6% and 47.6% of the variation, respectively. Soil moisture had a linear limiting effect on soil respiration for all ecosystems but spruce, where soil moisture was the limiting factor above a threshold value of about 50%vol. In the forest ecosystems, GPP of the ground vegetation were not reducing soil carbon effluxes, while in meadow it was. In meadow, the light response curve with GPP against PAR explained 32.7% of the variation in GPP while the cubic regression against air temperature explained 33.9%. No significant effect of soil moisture on GPP was detected. The exponential regression equations with air and soil temperature against soil respiration could be used to temporally extrapolate the occasional field measurements. The light response curve with GPP against PAR and the cubic regression with GPP against air temperature could also be used for temporal extrapolation. From the modelled soil respiration, annual soil respiration for the ecosystems in Laxemar, during 15th of March 2004 to 14th of March 2005, were estimated to be between 0.56 and 1.18 kg C/m2/y. Annual GPP of meadow was estimated to be between 0.49 and 0.54 kg C/m2/y, which gives a net ecosystem exchange for the meadow of between 0.38 and 0.66 kg C/m2/y, i.e. a significant loss of carbon to the atmosphere

211

Wetland vegetation establishment in L-Lake  

Energy Technology Data Exchange (ETDEWEB)

Wetland vegetation was transplanted from PAR Pond to L-Lake between January and August, 1987. Approximately 100,000 individual plants representing over 40 species were transplanted along the southern shoreline. Three zones of vegetation were created: (1) submersed/floating-leaved, (2) emergent, (3) upper emergent/shrub. During the summers of 1987, 1988, 1989, the Savannah River Ecology Laboratory sampled the vegetation in 54 permanent transects located in planted (N=32) and unplanted areas (N=22). The 1989 vegetation data from L-Lake were compared to 1985 data from PAR Pond.

Kroeger, S.R.

1990-07-01

212

Wetland vegetation establishment in L-Lake  

International Nuclear Information System (INIS)

Wetland vegetation was transplanted from PAR Pond to L-Lake between January and August, 1987. Approximately 100,000 individual plants representing over 40 species were transplanted along the southern shoreline. Three zones of vegetation were created: (1) submersed/floating-leaved, (2) emergent, (3) upper emergent/shrub. During the summers of 1987, 1988, 1989, the Savannah River Ecology Laboratory sampled the vegetation in 54 permanent transects located in planted (N=32) and unplanted areas (N=22). The 1989 vegetation data from L-Lake were compared to 1985 data from PAR Pond

213

Phytogeographical and ecological characteristics of the vegetation alliance Thero-Salicornion BrBl. 33 em. Tx. 50 growing on Continental salt-affected soils (Banat - Yugoslavia)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Synecology of the communities of the alliance Thero-Salicornion BrBl. 33 em. Tx. 50 growing on continental salt-affected soils (Banat, Yugoslavia) has been characterized on the basis of area type percentages and life form explanations, using methods of indicative geobotany.

Kneževi? Aleksa S.; Boža Pal P.; Milošev Dragiša S.; Ana?kov Goran T.

2002-01-01

214

Variability of alder-dominated forest vegetation along a latitudinal gradient in Slovakia  

Directory of Open Access Journals (Sweden)

Full Text Available Syntaxonmical revision of azonal forest vegetation with dominance of Alnus glutinosa and A. incana was done along a latitudinal transect of Slovakia. A data matrix consisting of 240 phytosociological relevés was obtained in accordance with the standard Zürich-Montpellier approach. Detrended correspondence analysis was used to clarify the relationships between the vegetation composition and environmental variables, whereas one-way ANOVA was applied to quantify the differences in site requirements of particular vegetation types. The unsupervised numerical classification resulted in identification of five clusters corresponding to the traditionally described and ecologically interpretable associations within the Euro-Siberian alder carr forests of Alnion glutinosae and the European broad-leaved floodplain forests of Alnion incanae: Carici elongatae-Alnetum glutinosae Schwickerath 1933 (alder carr forests on permanently waterlogged soils, Stellario-Alnetum glutinosae Lohmeyer 1957 (riparian alder vegetation on mesic to humid sites along small brooks, Piceo-Alnetum Mráz 1959 (submontane and montane oligotrophic spruce-alder forests on waterlogged habitats, Cardamino amarae-Alnetum incanae Šomšák 1961 (grey alder vegetation in spring fed areas and Alnetum incanae Lüdi 1921 (submontane and montane streamside grey alder forests on mesic sites. They significantly (P < 0.05 differed in the Ellenberg's indicator values for nutrients, moisture, temperature and altitude. These environmental variables were also established by DCA analysis as underlying sources of variation in alder-dominated forest composition. Special attention was given to discussion of their syntaxonomy, nomenclature, floristic structure, ecological features and distribution.

Michal Slezák

2013-02-01

215

Vegetative cover for low level radioactive waste sites  

International Nuclear Information System (INIS)

Low level radioactive waste (LLRW), hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the soil cover cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation down into the waste material. Turf type grasses are normally used as the principal vegetative cover for most sites. Consequently, the sites require periodic mowing and other expensive annual maintenance practices. The purpose of this 5 year study was to evaluate alternative plant material for use on LLRW sites that can be quickly and easily established and economically maintained, retards water infiltration, provides maximum year-round evapotranspiration, is ecologically acceptable and does not harm the closure cap.The results of the study suggest that two species of bamboo (Phyllostachys bissetii and Phyllostachys rubromarginata) could be utilized to quickly establish a long lived, low maintenance, final vegetative cover for the waste sites

216

Vegetated foreshores as coastal protection strategy: Coping with uncertainties and implementation  

Science.gov (United States)

Promising Building with Nature solutions for flood protection, such as vegetated foreshores, inherently have a dynamic nature. Therefore there is a relatively large degree of uncertainty with respect to their contribution to flood protection. This hampers innovation and the implementation of vegetated foreshores in flood risk management worldwide. We aim to develop new methods to assess how, and how much vegetated foreshores can contribute to flood risk reduction. The project will lead to a better understanding of (uncertainties in) the functioning and stability of these ecosystems and the development of novel governance arrangements. This requires integration of knowledge from ecology, biogeomorphology, hydraulic engineering, and governance. By field observations on several sites and flume measurements we will analyse fundamental ecological and physical processes for various types of wetland vegetations. The knowledge obtained will be applied in one implementation case study for a location in the Netherlands where dike reinforcement is needed in the future. This case study integrates fundamental knowledge from all the disciplines. It is used to design governance and implementation arrangements, and to demonstrate how vegetated foreshores can contribute to flood risk reduction. The project will provide the knowledge, methods and tools (e.g. a maptable) required for the design and implementation of vegetated foreshores as a safe, ecologically desirable, and cost effective alternative in flood management. Strong cooperation with end-users from the private sector, government and non-governmental organizations is embedded in the project to enhance the implementation of our findings in practice. In the full-paper, we present a multidisciplinary research agenda how to address the uncertainties hampering application, how to develop probabilistic tools to derive failure chance in legally imposed terms and how to derive at suitable governance arrangements.

Borsje, Bas; Bouma, Tjeerd; De Vries, Mindert; Timmermans, Jos; Vuik, Vincent; Hermans, Leon; Hulscher, Suzanne; Jonkman, Bas

2014-05-01

217

The importance of evolutionary history in studies of plant physiological ecology: examples from cerrados and forests of central Brazil / A importância da história evolutiva em estudos de ecofisiologia vegetal: exemplos dos cerrados e florestas do Brasil Central  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Estudos que comparam a fisiologia, anatomia e ecologia das espécies têm oferecido algumas das melhores apreciações sobre as limitações adaptativas e evolucionárias em plantas. Como resultado, a abordagem comparativa tem sido cada vez mais utilizada em estudos de ecofisiologia vegetal. A alta diversi [...] dade de espécies dos biomas brasileiros fornece excelentes oportunidades para estudos de ecofisiologia vegetal comparada, uma abordagem que poderia ser melhor explorada em pesquisas que visam a compreensão da evolução da forma e função em plantas. Neste artigo nós enfatizarmos a importância de considerar a informação filogenética no desenho e analises de estudos comparativos, utilizando como exemplos espécies lenhosas do cerrado e de mata de galeria (mata ripária). O uso de pares congenéricos, cada par contendo uma espécie do cerrado e uma espécie de floresta do mesmo gênero, aumenta o poder estatístico das análises, enquanto assegura concomitantemente a independência filogenética, uma condição essencial para inferência em estudos comparativos. Por exemplo, em um estudo comparativo de nove espécies do cerrado e nove de mata, não seria possível concluir que as espécies de cerrado e de mata diferem na razão de área foliar (LAR), área foliar especifica (SLA) e altura da plântula, se as relações filogenéticas forem ignoradas. Entretanto, se utilizarmos agrupamentos genéricos para contabilizar os efeitos filogenéticos, nós vamos encontrar que as plântulas de espécies de cerrado tem menores valores de LAR, SLA e altura da plântula. Muito da inércia filogenética observada para estes atributos em plântulas parece estar relacionada ao fato de que estas características se correlacionam fortemente com a massa da semente, que estudos anteriores demonstraram ser um atributo fortemente conservado em termos filogenéticos. Estes exemplos ressaltam a importância da informação filogenética em estudos comparativos. Abstract in english Studies that compare physiology, anatomy, and ecology across species have offered some of the best insight into adaptation and evolutionary constraints in plants. As a result, the comparative approach has become increasingly used in studies of plant physiological ecology. The high species diversity [...] of Brazilian biomes provides many excellent opportunities for comparative plant ecophysiology, and could be better exploited for understanding the evolution of plant form and function. In this paper we emphasize the importance of considering phylogenetic information for the design and analysis of comparative studies, relying on examples from comparisons of woody plants from cerrado and gallery (riparian) forests. The use of congeneric species pairs, each containing one cerrado species and one forest species of the same genus, greatly improves statistical power while assuring phylogenetic independence, an essential condition for inference in comparative studies. For example, in a study of seedlings of nine cerrado species and nine forest species, when we ignore phylogenetic relationships, it is not be possible to conclude that cerrado and forest species differ with regard to leaf area ratio (LAR), specific leaf area (SLA), or seedling height. If, however, we use the generic groupings to account for phylogenetic effects, then we find that seedlings of savanna species have lower LAR, SLA, and seedling height. Much of the phylogenetic inertia observed for these traits appears related to the fact that these traits are all strongly correlated with seed mass, which has been previously shown to be strongly conserved phylogenetically. These examples emphasize the importance of phylogenetic information in comparative studies.

William A., Hoffmann; Augusto C., Franco.

2008-09-01

218

Adopting national vegetation guidelines and the National Vegetation Information System (NVIS) framework in the Northern Territory  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Guidelines and core attributes for site-based vegetation surveying and mapping developed for the Northern Territory, are relevant to botanical research, forestry typing, rangeland monitoring and reporting on the extent and condition of native and non-native vegetated landscapes. These initiatives are consistent with national vegetation guidelines and the National Vegetation Information System (NVIS) framework. This paper provides a synopsis of vegetation site data collection, classification a...

Lewis, Donna L.; Brocklehurst, Peter B.; Thackway, Richard; Hill, Jason V.

2013-01-01

219

The distribution, dominance patterns and ecological niches of plankton functional types in Dynamic Green Ocean Models and satellite estimates  

Science.gov (United States)

We compare the spatial and temporal representation of phytoplankton functional types (pPFTs) in four different Dynamic Green Ocean Models (DGOMs; CCSM-BEC, NEMURO, PISCES and PlankTOM5) to derived phytoplankton distributions from two independent satellite estimates, with a particular focus on diatom distributions. Global annual mean surface biomass estimates for diatoms vary between 0.23 mmol C m-3 and 0.77 mmol C m-3 in the models, and are comparable to a satellite-derived estimate (0.41 mmol C m-3). All models consistently simulate a higher zonal mean diatom biomass contribution in the high latitudes than in the low latitudes, but the relative diatom contribution varies substantially between models with largest differences in the high latitudes (20% to 100% of total biomass). We investigate phytoplankton distribution in terms of annual and monthly mean dominance patterns, i.e. the distribution of locations where a given PFT contributes more than 50% to total biomass. In all models, diatoms tend to dominate large areas of the high latitudes of both hemispheres, and the area of the surface ocean dominated by diatoms is significantly higher in the models than in the satellite estimates. We estimate the realized ecological niches filled by the dominant pPFT at each location as a function of annual mean surface nitrate concentration (NO3), sea surface temperature (SST), and mixed layer depth. A general additive model (GAM) is used to map the probability of dominance of all pPFTs in niche and geographic space. Models tend to simulate diatom dominance over a wider temperature and nutrient range, whereas satellites confine diatom dominance to a narrower niche of low-intermediate annual mean temperatures (annual mean SST modelled probability of dominance explains the majority of the variance in the data (65.2-66.6%). For the satellite estimates, the explained deviance is much lower (44.6% and 32.7%). The differences in the representation of diatoms among models and compared to satellite estimates highlights the need to better resolve phytoplankton succession and phenology in the models. This work is part of the marine ecosystem inter-comparison project (MAREMIP).

Vogt, M.; Hashioka, T.; Payne, M. R.; Buitenhuis, E. T.; Le Quéré, C.; Alvain, S.; Aita, M. N.; Bopp, L.; Doney, S. C.; Hirata, T.; Lima, I.; Sailley, S.; Yamanaka, Y.

2013-11-01

220

Potential natural vegetation; 1 : 500 000  

International Nuclear Information System (INIS)

Potential natural vegetation is the reflection of the present ecological landscape potential. It presents the natural vegetation, which could be formed in the territory of Slovakia in future, if man stopped to influence the vegetation cover. In the territory of Slovakia it is, with minor exceptions, mainly the forest vegetation. The alpine zone of high mountains, steep exposed rocks in lower positions, and the areas of open water tables represent the mentioned exceptions. The prevailing part of the mapped units consists of willow poplar, alder, elm, oak, oakhornbeam, beech, fir-beech, spruce and dwarf pine forests. The presented map is a follow-up to the map Potential natural vegetation at scale 1 : 500 000 (Atlas Slovenskej socialistickej republiky, SAV, SUGK, Bratislava, 1980) and Karte der natuerlichen Vegetation Europas at scale 1 : 2 500 000 (Bundesamt fuer Naturschutz - ed., Bonn, 2000). (author)

 
 
 
 
221

Desempenho de uma semeadora-adubadora para plantio direto, em dois solos com diferentes tipos de cobertura vegetal Performance of a no-tillage seeder, in two soils with different types of vegetable coverages  

Directory of Open Access Journals (Sweden)

Full Text Available O desempenho operacional de uma semeadora-adubadora de plantio direto, versão soja e milho, foi avaliado em um Podzólico Vermelho-Amarelo câmbico, fase terraço, e um Latossolo Vermelho-Amarelo, da Zona da Mata de Minas Gerais. A máquina foi testada em três tipos de cobertura do solo e em duas velocidades de trabalho. Por ocasião do plantio, foram avaliados a patinagem do trator e da semeadora-adubadora, o consumo de combustível e a potência exigida, a distribuição de fertilizante e o nível de danos às sementes. Depois do plantio, foram avaliados o número de sementes distribuídas, o estande final, a profundidade de plantio e a distribuição longitudinal da semente. A uniformidade de distribuição longitudinal foi avaliada pela porcentagem de espaçamentos aceitáveis, distribuição dupla e falhas na distribuição, e pelo coeficiente de variação dos espaçamentos entre sementes. A demanda de potência foi maior no Podzólico, por sua maior densidade e resistência à penetração. Independentemente do tratamento, o número de sementes distribuídas e o estande final não apresentaram diferenças significativas. As sementes distribuídas não tiveram sua qualidade afetada pelos dosadores da máquina. A análise de variância não indicou diferença significativa entre os porcentuais de espaçamentos aceitáveis, a distribuição dupla e as falhas.The performance of a no-tillage seeder, version soybean and corn was evaluated under two classes of soil, a cambic Red-Yellow Podzolic terrace phase and a Red-Yellow Latosol, at Zona da Mata, MG. The machine was tested under three different vegetable coverages in two work speeds. During test, tractor and planter slipping, fuel consumption and the power required by the machine, distribution fertilizer, and seeds damage were evaluated. After planting, the number of seeds by hectare, final stand, planting depth and seed longitudinal distribution, were also evaluated. The uniformity of longitudinal distribution was measured for percentage of admissible spacing, pair distribution, failures on distribution and by coefficient variation of seed spacing. The demand of power was higher on podzolic, due to its higher density and resistance to penetration. Regardless of the type of treatment, the number of seeds distributed and the final stand obtained showed no significant difference and the depth average obtained in the test was close to the values foreseen in the control. The seeds distributed were not affected by dosage mechanism. The analysis of variance indicated no significant variation between the values of admissible spacing, the pair distribution and failures.

MILSON LOPES DE OLIVEIRA

2000-07-01

222

Desempenho de uma semeadora-adubadora para plantio direto, em dois solos com diferentes tipos de cobertura vegetal / Performance of a no-tillage seeder, in two soils with different types of vegetable coverages  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O desempenho operacional de uma semeadora-adubadora de plantio direto, versão soja e milho, foi avaliado em um Podzólico Vermelho-Amarelo câmbico, fase terraço, e um Latossolo Vermelho-Amarelo, da Zona da Mata de Minas Gerais. A máquina foi testada em três tipos de cobertura do solo e em duas veloci [...] dades de trabalho. Por ocasião do plantio, foram avaliados a patinagem do trator e da semeadora-adubadora, o consumo de combustível e a potência exigida, a distribuição de fertilizante e o nível de danos às sementes. Depois do plantio, foram avaliados o número de sementes distribuídas, o estande final, a profundidade de plantio e a distribuição longitudinal da semente. A uniformidade de distribuição longitudinal foi avaliada pela porcentagem de espaçamentos aceitáveis, distribuição dupla e falhas na distribuição, e pelo coeficiente de variação dos espaçamentos entre sementes. A demanda de potência foi maior no Podzólico, por sua maior densidade e resistência à penetração. Independentemente do tratamento, o número de sementes distribuídas e o estande final não apresentaram diferenças significativas. As sementes distribuídas não tiveram sua qualidade afetada pelos dosadores da máquina. A análise de variância não indicou diferença significativa entre os porcentuais de espaçamentos aceitáveis, a distribuição dupla e as falhas. Abstract in english The performance of a no-tillage seeder, version soybean and corn was evaluated under two classes of soil, a cambic Red-Yellow Podzolic terrace phase and a Red-Yellow Latosol, at Zona da Mata, MG. The machine was tested under three different vegetable coverages in two work speeds. During test, tracto [...] r and planter slipping, fuel consumption and the power required by the machine, distribution fertilizer, and seeds damage were evaluated. After planting, the number of seeds by hectare, final stand, planting depth and seed longitudinal distribution, were also evaluated. The uniformity of longitudinal distribution was measured for percentage of admissible spacing, pair distribution, failures on distribution and by coefficient variation of seed spacing. The demand of power was higher on podzolic, due to its higher density and resistance to penetration. Regardless of the type of treatment, the number of seeds distributed and the final stand obtained showed no significant difference and the depth average obtained in the test was close to the values foreseen in the control. The seeds distributed were not affected by dosage mechanism. The analysis of variance indicated no significant variation between the values of admissible spacing, the pair distribution and failures.

MILSON LOPES DE, OLIVEIRA; LUCIANO BAIÃO, VIEIRA; EVANDRO CHARTUNI, MANTOVANI; CAETANO MARCIANO DE, SOUZA; GUTEMBERG PEREIRA, DIAS.

1455-14-01

223

Ecological Species Groups of Hornbeam Forest Ecosystems in Southern Caspian (North of Iran  

Directory of Open Access Journals (Sweden)

Full Text Available Ecological species group were developed for hornbeam forest ecosystems in North of Iran that had been moderately disturbed. Species groups were determined from field observations and sample plot data arranged and analyzed in association tables. The groups were defined on the basis of species patterns of presence, absence and coverage values. Vegetation was sampled with randomized-systematic method. Vegetation data including density and cover percentage were estimated quantitatively within each quadrate and using the two-way indicator species analysis (TWINSPAN. The objectives of the study were to develop ecological species groups for lowland ecosystems types dominated by hornbeam in north of Iran, describe the site indicator values of species groups and increase our understanding of site-species relationships in moderately disturbed landscape in Khanikan lowland forests of Mazandaran province. Five vegetation groups were identified after the application of TWINSPAN programs. They are named after the characterizing species as follows: Menta aquatica (I, Oplismenus undulatifolius (II, Carex grioletia (III, Viola odarata (IV and Rubus caesius (V. Result have showed that II, III vegetation groups and I, II vegetation groups had the most (65.5% and the least (30% of Sorenson similarity coefficient, respectively. Apparently, similarity coefficient of differentiated vegetation groups was high.

H. Jalilvand

2007-01-01

224

Ecological land classification and terrestrial environment effects assessment for the Port Hope and Port Granby projects  

International Nuclear Information System (INIS)

The Ecological Land Classification system was developed to provide a standardized methodology for describing plant communities and wildlife habitat in southern Ontario. The method employs a hierarchical classification system. It can be applied at different levels of accuracy, i.e., at regional, sub-regional, and local scales with an increasing differentiation of vegetation communities. The standardization of the approach permits a comparison of vegetation communities from different sites and an evaluation of the rarity of these communities within the province. Further, the approach facilitates the monitoring of changes in terrestrial communities with time. These characteristics make Ecological Land Classification mapping a useful tool for environmental assessment such as the ones undertaken for the Port Hope and Port Granby Long-Term Waste Management Projects, which were conducted pursuant to the Canadian Environmental Assessment Act 1992. In the context of the Environmental Assessment for the Port Hope and Port Granby Projects, an Ecological Land Classification study was undertaken to characterize the terrestrial environment at regional, local and site levels. Vegetation patches (polygons) were delineated on the basis of air photo interpretation. The individual polygons were then visited for detailed inventory and classified to the most detailed level; that is to the vegetation type. Plant communities were then compared with those listed in the Ontario Natural Heritathose listed in the Ontario Natural Heritage Information Centre database to determine their rarity and to determine where they rank as Valued Ecosystem Components. Ecological Land Classification mapping results were used in the assessment of effects to Valued Ecosystem Components. A spatial analysis of the digitized vegetation maps showed the geographic extent of habitat losses and impairments due to various project works and activities. Landscape rehabilitation strategies and concepts were subsequently developed based on Ecological Land Classification inventory data and predicted effects. (author)

225

Desempenho de um trator operando em solo com diferentes tipos de cobertura vegetal Tractor performance in soil with different types of plants covering  

Directory of Open Access Journals (Sweden)

Full Text Available A eficiência de um trator para desenvolver esforço tratório depende da interação entre o rodado e o solo, envolvendo um complexo conjunto de fatores: característica do rodado, patinagem, transferência de peso do trator, tipo de solo, umidade, estado de compactação, tipo de cobertura do solo, entre outros, que proporcionam diferentes condições de trabalho e interferem no desempenho do trator. Assim, conduziu-se o presente trabalho com o propósito de avaliar alguns desses fatores no desempenho de um trator agrícola, em área coberta com diferentes tipos de cobertura vegetal (aveia, ervilhaca, nabo, aveia e nabo e sem cobertura. O trator foi submetido a cargas por meio do acoplamento a um escarificador de arrasto e instrumentado para a obtenção da força de tração, velocidade de deslocamento, patinagem e consumo de combustível sendo os dados armazenados por meio de um sistema de aquisição de dados. A patinagem foi maior onde a massa de matéria seca era maior, porém não influenciou na potência requerida na barra de tração. A melhor eficiência de tração foi obtida nas parcelas sem cobertura. O coeficiente de tração foi maior nos tratamentos com cobertura de aveia, ervilhaca e nabo comparados com a área sem cobertura. Conclui-se que a cobertura do solo interfere na capacidade do trator em desenvolver esforço para tracionar máquinas e implementos e que o tipo de cobertura pode causar mudanças na patinagem e na eficiência tratória.The efficiency of a tractor to draft development depends on the interaction among the wheeled and the soil where it moves and it involves a complex group of factors, such as: characteristic of the tire, slip, the tractor weight transfer, soil type, water texture and soil compactation, type of soil covering, among others. The aim of this work was to evaluate the acting of an agricultural tractor in an area covered with different types of plants. It was used five types of soil covering (oat, Vicia sativa, turnip, oat and V. sativa together and without cover. A load cell, pulse sensor, flow meters and a system of data acquisition, was used. The slip was larger where the mass of dry matter was larger, even so it didn't influence in the potency requested in the drawbar and in the consumption of fuel. The best traction efficiency was obtained in the portions without covering. The traction coefficient was larger in the treatments with covering of oat, Vicia sativa and turnip, when compared with the area without covering. It is ended that the covering of the soil interferes in the capacity of the tractor in developing effort for pull machines and the covering type can intervene in the slip and tractor efficiency.

Antonio Gabriel Filho

2004-12-01

226

Past and future scenarios of the effect of carbon dioxide on plant growth and transpiration for three vegetation types of southwestern France  

Directory of Open Access Journals (Sweden)

Full Text Available The sensitivity of an operational CO2-responsive land surface model (the ISBA-A-gs model of Météo-France to the atmospheric CO2 concentration, [CO2], is investigated for 3 vegetation types (winter wheat, irrigated corn, coniferous forest. Past (1960 and future (2050 scenarios of [CO2] corresponding to 320 ppm and 550 ppm, respectively, are explored. The sensitivity study is performed for 4 annual cycles presenting contrasting conditions of precipitation regime and air temperature, based on continuous measurements performed on the SMOSREX site near Toulouse, in southwestern France. A significant CO2-driven reduction of canopy conductance is simulated for the irrigated corn and the coniferous forest. The reduction is particularly large for corn, from 2000 to 2050 (–18%, and triggers a drop in optimum irrigation (–30 mm y?1. In the case of wheat, the response is more complex, with an equal occurrence of enhanced or reduced canopy conductance.

J.-C. Calvet

2007-04-01

227

Past and future scenarios of the effect of carbon dioxide on plant growth and transpiration for three vegetation types of southwestern France  

Directory of Open Access Journals (Sweden)

Full Text Available The sensitivity of an operational CO2-responsive land surface model (the ISBA-A-gs model of Météo-France to the atmospheric CO2 concentration, (CO2, is investigated for 3 vegetation types (winter wheat, irrigated maize, coniferous forest. Past (1960 and future (2050 scenarios of (CO2 corresponding to 320 ppm and 550 ppm, respectively, are explored. The sensitivity study is performed for 4 annual cycles presenting contrasting conditions of precipitation regime and air temperature, based on continuous measurements performed on the SMOSREX site near Toulouse, in southwestern France. A significant CO2-driven reduction of canopy conductance is simulated for the irrigated maize and the coniferous forest. The reduction is particularly large for maize, from 2000 to 2050 (?18%, and triggers a drop in optimum irrigation (?30 mm y?1. In the case of wheat, the response is more complex, with an equal occurrence of enhanced or reduced canopy conductance.

J.-C. Calvet

2008-01-01

228

An integrated remote sensing approach for identifying ecological range sites. [parker mountain  

Science.gov (United States)

A model approach for identifying ecological range sites was applied to high elevation sagebrush-dominated rangelands on Parker Mountain, in south-central Utah. The approach utilizes map information derived from both high altitude color infrared photography and LANDSAT digital data, integrated with soils, geological, and precipitation maps. Identification of the ecological range site for a given area requires an evaluation of all relevant environmental factors which combine to give that site the potential to produce characteristic types and amounts of vegetation. A table is presented which allows the user to determine ecological range site based upon an integrated use of the maps which were prepared. The advantages of identifying ecological range sites through an integrated photo interpretation/LANDSAT analysis are discussed.

Jaynes, R. A.

1983-01-01

229

Ecological aspects of the use of fuels and lubricants from plant and animal sources  

International Nuclear Information System (INIS)

In attacking the problems involved in preventing or mitigating the growing ecological crisis and its consequences, the leading place is occupied by the search for an alternative ecologically clean raw material for the production of various types of energy and the manufacture of chemical products. Fuels and lubricants, whether of petroleum or synthetic origin, pose a significant threat to the environment. Here, the authors are generally speaking of ecologically dangerous products, but in many cases even toxic products. They pollute the air, soil, and water with automotive exhaust, spills of used oils, and the incineration and burial of wastes. Vegetable and animal fats do not have any of the shortcomings that are enumerated above. They are biodegradable, nontoxic, and do not form xenobiotics. The use of fats and oils as base stocks or components of fuels and lubricants may well facilitate and accelerate the solution of certain ecological problems. 26 refs., 1 fig., 3 tabs

230

Behavior of the vegetable crops section in three types of food retail stores in Campo Grande, Brazil Desempenho da seção de hortaliças em equipamentos varejistas de alimentos  

Directory of Open Access Journals (Sweden)

Full Text Available The behavior of the fresh fruits and vegetable produce section was evaluated, under the point of view of the consumer, in three types of food retail stores in Campo Grande, Brazilian southeast: a grocery store ("quitanda", a supermarket, and an open-air market. A quantitative-descriptive survey was conducted with 120 individuals, responsible for purchasing fresh fruit and vegetable produce for their homes. To accomplish that, twelve variables were investigated and adapted from the parameters used in the SERVQUAL model, in which the attributes of the retail outlet are pointed out, such as store hygiene and cleanliness and manner by which produce is displayed; employee training traits, such as courtesy and helpfulness; and quality, price range, and variety of the produce for sale. The results reveal that shopping for grocery is done weekly; 80% of the shoppers interviewed do their shopping in supermarkets and 94% do theirs in open-air markets. The open-air market had the best results in the attributes for which they were evaluated when compared with the grocery store and the supermarket. The study also points out that the older the shopper the more often he/she does grocery shopping.Neste estudo foi avaliado, sob o ponto de vista do consumidor, o desempenho da seção de hortaliças em três equipamentos varejistas de alimentos em Campo Grande(MS: uma mercearia (quitanda, um supermercado e uma feira-livre. Foi realizada uma pesquisa quantitativo-descritiva com 120 indivíduos, responsáveis pelas compras de hortaliças para suas residências. Para tanto, foram investigadas doze variáveis adaptadas das dimensões do modelo SERVQUAL, onde se destacam os atributos do equipamento varejista como higiene e limpeza da loja e exposição dos produtos; capacitação dos funcionários como atendimento e cortesia; e atributos do produto como qualidade, variedade e preço. Os resultados mostram que as compras de hortaliças são realizadas semanalmente, sendo que 80% dos consumidores as realizam em supermercados e 94% em feiras-livres. A feira livre apresentou o melhor desempenho nos atributos em que foi avaliada quando comparada com a quitanda e o supermercado. Esse estudo, também revela que, quanto maior a idade do consumidor, maior sua freqüência de compra.

Dario de O Lima-Filho

2009-03-01

231

Behavior of the vegetable crops section in three types of food retail stores in Campo Grande, Brazil / Desempenho da seção de hortaliças em equipamentos varejistas de alimentos  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Neste estudo foi avaliado, sob o ponto de vista do consumidor, o desempenho da seção de hortaliças em três equipamentos varejistas de alimentos em Campo Grande(MS): uma mercearia (quitanda), um supermercado e uma feira-livre. Foi realizada uma pesquisa quantitativo-descritiva com 120 indivíduos, res [...] ponsáveis pelas compras de hortaliças para suas residências. Para tanto, foram investigadas doze variáveis adaptadas das dimensões do modelo SERVQUAL, onde se destacam os atributos do equipamento varejista como higiene e limpeza da loja e exposição dos produtos; capacitação dos funcionários como atendimento e cortesia; e atributos do produto como qualidade, variedade e preço. Os resultados mostram que as compras de hortaliças são realizadas semanalmente, sendo que 80% dos consumidores as realizam em supermercados e 94% em feiras-livres. A feira livre apresentou o melhor desempenho nos atributos em que foi avaliada quando comparada com a quitanda e o supermercado. Esse estudo, também revela que, quanto maior a idade do consumidor, maior sua freqüência de compra. Abstract in english The behavior of the fresh fruits and vegetable produce section was evaluated, under the point of view of the consumer, in three types of food retail stores in Campo Grande, Brazilian southeast: a grocery store ("quitanda"), a supermarket, and an open-air market. A quantitative-descriptive survey was [...] conducted with 120 individuals, responsible for purchasing fresh fruit and vegetable produce for their homes. To accomplish that, twelve variables were investigated and adapted from the parameters used in the SERVQUAL model, in which the attributes of the retail outlet are pointed out, such as store hygiene and cleanliness and manner by which produce is displayed; employee training traits, such as courtesy and helpfulness; and quality, price range, and variety of the produce for sale. The results reveal that shopping for grocery is done weekly; 80% of the shoppers interviewed do their shopping in supermarkets and 94% do theirs in open-air markets. The open-air market had the best results in the attributes for which they were evaluated when compared with the grocery store and the supermarket. The study also points out that the older the shopper the more often he/she does grocery shopping.

Dario de O, Lima-Filho; Anderson S, Hokama; Caroline P, Spanhol.

2009-03-01

232

Canopy reflectance modelling of semiarid vegetation  

Science.gov (United States)

Three different types of remote sensing algorithms for estimating vegetation amount and other land surface biophysical parameters were tested for semiarid environments. These included statistical linear models, the Li-Strahler geometric-optical canopy model, and linear spectral mixture analysis. The two study areas were the National Science Foundation's Jornada Long Term Ecological Research site near Las Cruces, NM, in the northern Chihuahuan desert, and the HAPEX-Sahel site near Niamey, Niger, in West Africa, comprising semiarid rangeland and subtropical crop land. The statistical approach (simple and multiple regression) resulted in high correlations between SPOT satellite spectral reflectance and shrub and grass cover, although these correlations varied with the spatial scale of aggregation of the measurements. The Li-Strahler model produced estimated of shrub size and density for both study sites with large standard errors. In the Jornada, the estimates were accurate enough to be useful for characterizing structural differences among three shrub strata. In Niger, the range of shrub cover and size in short-fallow shrublands is so low that the necessity of spatially distributed estimation of shrub size and density is questionable. Spectral mixture analysis of multiscale, multitemporal, multispectral radiometer data and imagery for Niger showed a positive relationship between fractions of spectral endmembers and surface parameters of interest including soil cover, vegetation cover, and leaf area index.

Franklin, Janet

1994-01-01

233

Final vegetative cover for closed waste sites  

International Nuclear Information System (INIS)

Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as an interim vegetative cover for most sites. This coverage allows for required monitoring of the closure cap for settlement and maintenance activities. The purpose of this five year study was to evaluate plant materials for use on wastes sites after the post-closure care period that are quickly and easily established and economically maintained, retard water infiltration, provide maximum year-round evapotranspiration, are ecologically acceptable and do not harm the closure cap. The results of the study suggest that two species of bamboo (Phyllostachys (P.) bissetii and P. rubromarginata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites after surveillance and maintenance requirements have ceased

234

Representation of natural vegetation in protected areas: Capturing the geographic range  

Science.gov (United States)

Current conservation strategies for plant and animal species rarely address the need to protect the species throughout its geographic range thereby capturing potential genetic and ecological variation. We examined the degree that existing protected areas in the western United States satisfied this goal for four widespread vegetation cover types. We used latitude and longitude to stratify the distribution of these types into 16 cells, each of which was further stratified by up to five elevation classes. While protection of some vegetation types was high in parts of their range, it was minimal to nonexistent in other parts. While it is yet to be shown that protecting a given species throughout its geographic range is essential for its long-term existence, in the face of often unpredictable environmental changes, it seems a prudent course to follow. Our results suggest that if full range protection is a conservation goal, the existing network of protected areas may be inadequate for the task.

Scott, J.M.; Murray, M.; Wright, R.G.; Csuti, B.; Morgan, P.; Pressey, R.L.

2001-01-01

235

Pollination ecology of Tabebuia aurea (Manso) Benth. & Hook. and T. ochracea (Cham.) Standl. (Bignoniaceae) in Central Brazil cerrado vegetation / Ecologia da polinização de Tabebuia aurea (Manso) Benth. & Hook. e T. ochracea (Cham.) Standl. (Bignoniaceae) em cerrado do Brasil Central  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Foram investigadas a ecologia da polinização e a biologia reprodutiva de Tabebuia aurea (Manso) Benth. & Hook. e T. ochracea (Cham.) Standl. em uma área de cerrado em Brasília (DF) Brasil. Estas espécies ocorrem simpatricamente, florescem massiva e sincronicamente, por aproximadamente um mês, durant [...] e a estação seca (julho a setembro). Ambas espécies têm estruturas florais similares, antese diurna, corola tubular e são produtoras de néctar. Quatorze espécies de abelhas visitaram ambas Tabebuia, porém somente três espécies de Centris e Bombus morio foram consideradas polinizadores potenciais, devido a alta freqüência e à eficiência no transporte do pólen. Os testes de polinização artificial, demonstraram que T. aurea e T. ochracea são auto-incompatíveis, com auto-incompatibilidade de ação tardia. A proporção de frutos maturados resultantes de polinização cruzada foi baixa (T. aurea 17,2% e T. ochracea 12,3%) em ambas espécies, considerando o grande número de flores desabrochadas, sugerindo falta de recursos maternos. A grande quantidade de sementes por frutos (cerca de 92 em T. aurea e 285 em T. ochracea) deve representar o investimento materno nos óvulos fertilizados que possuem maior vigor. Abstract in english The pollination ecology and breeding systems of Tabebuia aurea (Manso) Benth. & Hook., and T. ochracea (Cham.) Standl. were investigated in an area of cerrado vegetation in the Federal District of Brazil. These species occur sympatrically, flower massively and synchronously for a month, during the d [...] ry season (July to September). Both have diurnal anthesis, with similar floral structures, a yellow tubular corolla and produce nectar. Fourteen species of bees visited both Tabebuia species, but, only three Centris species and Bombus morio, were considered potential pollinators, because of their high frequency on the flowers and their efficiency in carrying pollen. Tests on the breeding systems of T. aurea and T. ochracea demonstrated that boths species are self-incompatible, with late-acting self-incompatibility. The proportion of fruit set from cross pollination (T. aurea 17.2% and T. ochracea 12.3%) in both species was low considering the great number of flowers displayed. This suggests a lack of maternal resources for fruit-set. The great amount of seeds per fruit (about 92 in T. aurea and 285 in T. ochracea) may represent an investment of maternal resources allocated on higher quality of fertilized ovules.

MARILUZA GRANJA, BARROS.

2001-09-01

236

MAP OF ECOLOGICAL UNITS IN ROMANIA  

Directory of Open Access Journals (Sweden)

Full Text Available The ecological units were delineated based on the ensemble of life conditions whose variety is defined by the specific association of various conditions of climate, relief and lithology, hydrology, vegetable formations and soils, including also the anthropic influence. In the Romania territory 20 ecoregions were delineated, hierarchically grouped in 10 ecological domains and 4 ecological subzones belonging to 2 ecological zones (cold temperate and temperate. Each ecological regions (ecoregions is shortly characterized from following point of views: climatic, topographical, lithological, pedological and land use.

N. Florea

2005-10-01

237

Applications of ERTS data to coastal wetland ecology with special reference to plant community mapping and typing and impact of man. [Delaware, Maryland, Virginia, South Carolina, and Georgia  

Science.gov (United States)

Complete seasonal ERTS-1 coverage of Atlantic coastal wetlands from Delaware Bay to Georgia provides a basis for assessment of temporal data for wetland mapping, evaluation, and monitoring. Both MSS imagery and digital data have proved useful for gross wetland species delineation and determination of the upper wetland boundary. Tidal effects and (band to band or seasonal) spectral reflectance differences make it possible to type vegetatively coastal wetlands in salinity related categories. Management areas, spoil disposal sites, drainage ditches, lagoon-type developments and highway construction can be detected indicating a monitoring potential for the future. A northern test site (Maryland-Virginia) and a southern test site (Georgia-South Carolina), representing a range of coastal marshes from saline to fresh, were chosen for intensive study. Wetland maps were produced at various scales using both ERTS imagery (bands 5 and 7) and digital data (bands 4, 5 and 7).

Anderson, R. R.; Carter, V. P.; Mcginness, J.

1974-01-01

238

Vegetation state in the alienation zone after the Chernobyl accident  

International Nuclear Information System (INIS)

Vegetation state within the alienation zone on the territory of formed state farm 'Savichi' of the Bragin region was studied. 9 agroecosystem associations of the Braun-Blanguet system were selected. Their ecological, biological and economic characteristics are given. The research has shown that the content of Sr 90 in vegetative mass of most agroecosystem associations exceeded normative level. (authors)

239

Desempenho de um trator operando em solo com diferentes tipos de cobertura vegetal / Tractor performance in soil with different types of plants covering  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A eficiência de um trator para desenvolver esforço tratório depende da interação entre o rodado e o solo, envolvendo um complexo conjunto de fatores: característica do rodado, patinagem, transferência de peso do trator, tipo de solo, umidade, estado de compactação, tipo de cobertura do solo, entre o [...] utros, que proporcionam diferentes condições de trabalho e interferem no desempenho do trator. Assim, conduziu-se o presente trabalho com o propósito de avaliar alguns desses fatores no desempenho de um trator agrícola, em área coberta com diferentes tipos de cobertura vegetal (aveia, ervilhaca, nabo, aveia e nabo e sem cobertura). O trator foi submetido a cargas por meio do acoplamento a um escarificador de arrasto e instrumentado para a obtenção da força de tração, velocidade de deslocamento, patinagem e consumo de combustível sendo os dados armazenados por meio de um sistema de aquisição de dados. A patinagem foi maior onde a massa de matéria seca era maior, porém não influenciou na potência requerida na barra de tração. A melhor eficiência de tração foi obtida nas parcelas sem cobertura. O coeficiente de tração foi maior nos tratamentos com cobertura de aveia, ervilhaca e nabo comparados com a área sem cobertura. Conclui-se que a cobertura do solo interfere na capacidade do trator em desenvolver esforço para tracionar máquinas e implementos e que o tipo de cobertura pode causar mudanças na patinagem e na eficiência tratória. Abstract in english The efficiency of a tractor to draft development depends on the interaction among the wheeled and the soil where it moves and it involves a complex group of factors, such as: characteristic of the tire, slip, the tractor weight transfer, soil type, water texture and soil compactation, type of soil c [...] overing, among others. The aim of this work was to evaluate the acting of an agricultural tractor in an area covered with different types of plants. It was used five types of soil covering (oat, Vicia sativa, turnip, oat and V. sativa together and without cover). A load cell, pulse sensor, flow meters and a system of data acquisition, was used. The slip was larger where the mass of dry matter was larger, even so it didn't influence in the potency requested in the drawbar and in the consumption of fuel. The best traction efficiency was obtained in the portions without covering. The traction coefficient was larger in the treatments with covering of oat, Vicia sativa and turnip, when compared with the area without covering. It is ended that the covering of the soil interferes in the capacity of the tractor in developing effort for pull machines and the covering type can intervene in the slip and tractor efficiency.

Antonio, Gabriel Filho; Suedêmio de L., Silva; Alcir J., Modolo; João C. M. da, Silveira.

2004-12-01

240

Tipos de estacas e substratos na propagação vegetativa da menta (Mentha arvensis L.) / Types of cuttings and substrates in the vegetative propagation of mint (Mentha arvensis L.)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O trabalho teve como objetivo avaliar a propagação vegetativa da menta utilizando diferentes tipos de estacas e substratos. O experimento foi conduzido no Horto de Plantas Medicinais da Unimontes, campus Janaúba - MG. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema f [...] atorial 2 x 4 (dois tipos de estacas e quatro diferentes substratos) com quatro repetições, sendo cada parcela representada por seis estacas. Foram analisadas as variáveis comprimento de parte aérea e de raízes, massa seca de parte aérea e de raízes e número total de brotações formadas por planta. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Scott-Knott a 5% de probabilidade. A interação entre os fatores estacas e substratos não foi significativa para as variáveis estudadas, passando-se a estudar o efeito isolado de cada fator. A propagação de Mentha arvensis L. pode ser realizada tanto por estacas apicais como medianas, utilizando o substrato solo + areia + esterco bovino (2:1:1) para a produção de mudas de qualidade. Abstract in english The purpose of the study was to evaluate the vegetative propagation using different types of mint cuttings and substrates. The experiment was conducted in the Garden of Medicinal Plants of Unimontes, in Janaúba - MG. The experimental design was completely randomized (CRD) in 2 x 4 factorial schemes [...] (two types of poles and four different substrates) with four replications and each plot was represented by six cuttings. The variables analyzed were the length of the shoots and roots, the dry matter of the shoots and roots and the total number of shoots per plant. The data were subject to ANOVA and the means were compared by Scott-Knott's test at 5% of probability. The interaction among stem cuttings and substrates was not significant for the variables studied, thus, the isolated effect of each factor was studied. The propagation of Mentha arvensis L. can be performed either by apical cuttings as medians, using the substrate soil + sand + manure bovine (2:1:1) for the production of quality seedlings.

H.T.R, Amaro; J.R, Silveira; A.M.S de S, David; M.A.V de, Resende; J.A.S., Andrade.

 
 
 
 
241

Environmental Impact of Flooding in the Main (Smallwood) Reservoir of the Churchill Falls Power Plant, Labrador, Canada. I. Background and Descriptions of Flooded Conditions Related to Vegetation and Land Cover Types  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper, the first in a series provides the background of the project, reports on the early phases of construction with the descriptions of the pre and post flooded conditions related to vegetation and land cover types surrounding the reservoir. Currently there are plans to develop the so called “Lower Churchill Area” by establishing new power plants at Gull Island and at Muskrat Falls with associated reservoirs. These new plants would use the discharged water of the plant from Churchi...

Roberts, Bruce A.; Denes Bajzak

2011-01-01

242

Respostas fisiológicas da laranjeira 'Pêra' aos sistemas de manejo de cobertura permanente do solo nas entrelinhas / Physiological responses of orange trees to permanent groundcover vegetation types  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A presença de plantas de cobertura permanente nas entrelinhas dos pomares pode comprometer a absorção de água e a fisiologia das laranjeiras. O objetivo deste estudo foi caracterizar as relações entre as variáveis fisiológicas das folhas das laranjeiras e o teor de água de um Argissolo Vermelho dist [...] rófico latossólico textura arenosa/média em sistemas de cobertura permanente do solo na entrelinha com gramínea "grama mato-grosso" ou "batatais" (Paspalum notatum), leguminosa amendoim forrageiro (Arachis pintoi) e vegetação espontânea. O estudo foi realizado em um experimento de laranjeira 'Pêra', instalado em 1993, em Alto Paraná, no noroeste do Paraná. Entre 1999 a 2002, foram realizadas determinações do teor de água em camadas de solo estratificadas em 10 e 20 cm até 1 m de profundidade no centro da entrelinha e no limite da projeção da copa das laranjeiras, complementadas com medidas da taxa de fotossíntese, da condutância estomática e do potencial da água das folhas das laranjeiras. As respostas fisiológicas das folhas da laranjeira 'Pêra' apresentaram dependência específica aos teores de água das camadas de solo e dos sistemas de manejo da cobertura permanente nas entrelinhas. A condutância estomática das folhas da laranjeira dependeu dos teores de água da camada subsuperficial de textura média manejada com a leguminosa no centro da entrelinha. O potencial da água nas folhas da laranjeira mostrou-se dependente dos teores de água do solo na camada superficial arenosa sob o manejo da gramínea no centro da entrelinha e no limite da projeção da copa das laranjeiras. A manutenção das entrelinhas vegetadas com a gramínea no horizonte superficial arenoso aumentou a disponibilidade de água para as laranjeiras. Abstract in english The presence of a groundcover in-between tree rows in orange orchards can affect the water uptake and physiology of the orange trees. The objective of this study was to characterize the relationships between the physiological variables of orange leaf and soil water content in a Paleudults in groundc [...] over management systems with bahiagrass (Paspalum notatum), leguminous perennial peanut (Arachis pintoi) and spontaneous vegetation. The study was performed in in an experimental "Pêra" orange orchard established in 1993 in Alto Paraná, northwestern Paraná state, Brazil. From 1999 to 2002, the soil water content was determined in stratified soil layers up to the 1.00 m depth in-between the tree rows and within the canopy projection. The photosynthesis rate, stomatal conductance and leaf water potential of Pêra orange trees were also measured. The physiological response of the leaves of the orange trees depended specifically on the content of soil water and type of permanent groundcover vegetation in-between rows. With perennial peanut planted in-between the rows, the stomatal conductance of the orange leaves depended on the water content of the subsurface sandy clay loam soil layer. Under bahiagrass groundcover, the leaf water potential depended on the content of soil water in the sandy surface horizon in-between the rows and within the canopy projection. Bahiagrass groundcover on the sandy surface horizon increased water availability for the orange trees.

Jonez, Fidalski; Celso Jamil, Marur; Cássio Antonio, Tormena.

1307-13-01

243

Vegetative propagation in Piperaceae species  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Piperaceae species of forest remnants of Maringá, Paraná, Brazil present vegetative propagation through root or stem (stolon). This reproduction type was verified in Piper amalago L., P. arboreum Aublet, P. xylosteoides (Kunth) Steud., Peperomia parnassifolia Miq. and Ottonia martiana Miq. Root and stem branches of these species were analyzed anatomically. Results indicated that the vegetative propagation in Piperaceae should be studied in other forests. New and additional studies should be...

Luiz Antonio Souza; Ismar Sebastião Moscheta; Káthia Socorro Mathias Mourão; Adriana Lenita Meyer Albiero; Maísa de Carvalho Iwazaki; Jonathas Henrique Georg de Oliveira; Sônia Maciel da Rosa

2009-01-01

244

Ecological Distribution of Indicator Species and Effective Edaphical Factors on the Northern Iran Lowland Forests  

Directory of Open Access Journals (Sweden)

Full Text Available The objectives of this research were to identify the ecological species groups and study the relationship between topographic and edaphic factors with plant species to determine the main factors affecting the separation of vegetation types in Khanikan lowland forests of Mazandaran province (North of Iran. Vegetation was sampled with randomized-systematic method. Vegetation data including density and cover percentage were estimated quantitatively within each quadrate and using the two-way indicator species analysis (TWINSPAN. Vegetation was classified into different groups. The topographic conditions were recorded in quadrate locations. Soil samples were taken from organic horizon (litter layer and mineral layers (0-10, 10-20 and 20-30 cm. Soil acidity, bulk density, saturation moisture, electrical conductivity, organic carbon, total nitrogen, cation exchangeable capacity, available phosphorous, soil texture, lime, biomass of earthworms, litter carbon and litter nitrogen were measured. Multivariate techniques were used to analyze the collected data. The results indicated that the vegetation distribution patters were mainly related to soil characteristics such as pH, bulk density, texture, phosphorous, organic carbon, nitrogen and CEC. Totally, considering the habitat conditions and ecological needs, each plant species has a significant relation with soil properties.

Y. Kooch

2007-01-01

245

Efectos del cambio climático en la diversidad vegetal del corredor de conservación comunitaria Reserva Ecológica El Ángel- Bosque Protector Golondrinas en el norte del Ecuador / The effects of climate change on vegetative diversity in the El Angel Ecological Reserve-Golondrinas Protected Forest community conservation corridor in northern Ecuador  

Scientific Electronic Library Online (English)

Full Text Available SciELO Peru | Language: Spanish Abstract in spanish Para estimar el impacto del cambio climático en el corredor de conservación comunitaria Reserva Ecológica El Ángel - Bosque Protector Golondrinas en el norte del Ecuador se utilizó modelos de distribución potencial generados con MARS de 413 especies vegetales, usando 19 variables bioclimáticas de Wo [...] rldclim con el clima actual y para el 2080 estas mismas variables fueron estimadas de acuerdo al modelo HadCM3-A2. En base a esta información se generaron mapas de riqueza tanto para el presente como para el 2080. Para el área del corredor se han identificado zonas donde se estima que haya cambios de riqueza y donde potencialmente las especies podrían colonizar nuevas áreas o donde se extinguirán. Esto permite determinar el grado de perturbación que sufrirán los ecosistemas por efecto del cambio climático. La tendencia general de las especies estudiadas muestra que colonizarán altitudes más elevadas, cambiando la estructura de los ecosistemas naturales actuales. Toda esta información muestra que para afrontar potenciales impactos en la flora de los ecosistemas de montaña es necesario formar corredores que conecten altitudinalmente áreas naturales protegidas, que permitan la migración de especies y por ende la conservación de la biodiversidad. Abstract in english In order to estimate the impact of climate change on the El Angel Ecological Reserve - Golondrinas Protected Forest community conservation corridor, potential distribution models generated using MARS of 413 vegetative species were applied using 19 Worldclim bioclimatic variables for current climate, [...] and for the year 2080, these same variables were estimated according to the HadCM3-A2 general circulation model. Based on this information, richness maps were developed for the present and for 2080. In the area of the corridor, zones were identified where changes in richness were predicted, where species could potentially colonize, or where species could become extinct. This allows the determination of the level of disturbance that the ecosystems will suffer with climate change. The general tendency of the species studied shows that they will colonize higher altitudes thus changing the structures of current natural ecosystems. All of this information demonstrates that to deal with potential impacts on the flora of mountain ecosystems it will be necessary to create corridors that will connect protected areas located at differing altitudes and thus permit species migration that will in turn conserve biodiversity.

Tania, Delgado; David, Suárez-Duque.

2009-12-01

246

Is New Zealand vegetation really 'problematic'? Dansereau's puzzles revisited.  

Science.gov (United States)

Over four decades ago, Pierre Dansereau, the noted North American ecologist, proposed six features of New Zealand vegetation as being problematic or unusual in a global context. We examine his propositions in the light of current ecological knowledge to determine whether or not these can still be considered unusual characteristics of New Zealand vegetation. (1) 'Climatic change is still progressing' resulting in disequilibrium between species' distributions and the present climate. New data and methods of analysis now available have removed the impression that Dansereau gained of imprecise zonation, unclear vegetation/climate relations and missing vegetation types. Communities cited as having regeneration failure can now be seen as even-aged stands that developed after major disturbance, although there are other, also non-climatic, explanations. However, the cause of the Westland 'Nothofagus gap' has become more, rather than less, controversial. (2) 'Continuity of community composition defies classification' and 'Very few New Zealand associations have faithful species' are correct observations, but perhaps equally true of vegetation elsewhere. Dansereau's assertion of low species richness in New Zealand is not supported by the comparative data available. (3) 'Lack of intolerant [i.e. mid-seral] trees …' is not evident with newer information. The order of species in succession, seen as unclear by Dansereau, has been determined by a range of approaches, largely confirming each other. (4) 'Discrepancies of form and function …' in divaricate shrubs and widespread heteroblasty are still controversial, with many more explanations. Several abiotic explanations have failed to stand up to investigation. Explanations in terms of herbivory have been well supported, although the extinction of the large avian herbivores makes certainty impossible. (5) 'Incidence of hybridization …' remains problematic. We do not know whether the incidence is unusually high, as Dansereau alleged, but the limited comparative data available suggest not. (6) The 'overwhelming … competing power of exotics' is strongly context dependent. They are prominent in many non-forest habitats. It seems that they are drivers of the vegetation change in some habitats, yet passengers after disturbance in others. Invasions can be slow, and may still be very incomplete in some ecosystem types. Whether exotics will eventually take over in most communities, or whether the native species will 'laugh them to scorn' as Cockayne suggested, only time will tell. In conclusion, some aspects of New Zealand's vegetation seem less unusual with increased knowledge, but others remain 'problems'. PMID:21929714

Wilson, J Bastow; Lee, William G

2012-05-01

247

Vegetation communities associated with the 100-Area and 200-Area facilities on the Hanford Site  

International Nuclear Information System (INIS)

The Hanford Site, Benton County, Washington, lies within the broad semi-arid shrub-steppe vegetation zone of the Columbia Basin. Thirteen different habitat types on the Hanford Site have been mapped in Habitat Types on the Hanford Site: Wildlife and Plant Species of Concern (Downs et al. 1993). In a broad sense, this classification is correct. On a smaller scale, however, finer delineations are possible. This study was conducted to determine the plant communities and estimate vegetation cover in and directly adjacent to the 100 and 200 Areas, primarily in relation to waste sites, as part of a comprehensive ecological study for the Compensation Environmental Response, Compensation, and Liability Act (CERCLA) characterization of the 100 and 200 Areas. During the summer of 1993, field surveys were conducted and a map of vegetation communities in each area, including dominant species associations, was produced. The field surveys consisted of qualitative community delineations. The community delineations described were made by field reconnaissance and are qualitative in nature. The delineations were made by visually determining the dominant plant species or vegetation types and were based on the species most apparent at the time of inspection. Additionally, 38 transects were run in these plant communities to try to obtain a more accurate representation of the community. Because habitat disturbances from construction/operations activities continue to occur in these areas, users of this information should be cautious in applying these maps without a current ground survey. This work will complement large-scale habitat maps of the Hanford Site

248

The Jena Diversity-Dynamic Global Vegetation Model (JeDi-DGVM): a diverse approach to representing terrestrial biogeography and biogeochemistry based on plant functional trade-offs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Terrestrial biosphere models typically abstract the immense diversity of vegetation forms and functioning into a relatively small set of predefined semi-empirical plant functional types (PFTs). There is growing evidence, however, from the field ecology community as well as from modelling studies that current PFT schemes may not adequately represent the observed variations in plant functional traits and their effect on ecosystem functioning. In this paper, we introduce the Jena Diversit...

Pavlick, R.; Drewry, D. T.; Bohn, K.; Reu, B.; Kleidon, A.

2013-01-01

249

Evaluation of Ecological Capability of West and North West of Tehran for Ultimate Urban Development  

Directory of Open Access Journals (Sweden)

Full Text Available The goal underlying the process of evaluating ecological capability of district 22 of Tehran as the main part of west and north west of Tehran is to realize the potential capability of land within practical application to achieve communication and interaction between human activities, society and the land potential to gain land preparation. To do so, in first place, an area of 5700 hectares, as district 22, was specified, maps of sustainable ecological resources (including physiography, type of soil, type and density of vegetation, geology and petrology and unsustainable resources (including maps for water resources, wild life habitats were prepared. On second stage the maps of land form units by using geographic information system (GIS were provided by the over laying maps of slope, direction and elevation level. The environmental unit maps were prepared by overlapping the soil type and vegetation maps. In the next stage the ecological models of different stratum the environmental information included in the tables were adjusted, coded and were then confirmed with the ecological models of land applications in Iran and the ecological models of different classes of application were prepared for district 22 through a mathematical model and subsequently, the maps of application classes via GIS was prepared. The findings of the ecological potentials of district 22 shows that except the hillside parts, the region has potential classification 2 for urban development. For an outdoor recreation, the entire region is in class 1 (suitable and has first and second potential for indoor recreation. For agriculture and animal husbandry the region has the potential 5 and only in a part of the region due to depth of the soil, it has potential 4 for agricultural and animal husbandry development. The region has potential 4 for supported woods application, the reason of this figure is low amount of water reserve and special physiography of the region.

J. Nouri

2002-01-01

250

The South African National Vegetation Database: history, development, applications, problems and future  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english Southern Africa has been recognised as one of the most interesting and important areas of the world from an ecological and evolutionary point of view. The establishment and development of the National Vegetation Database (NVD) of South Africa enabled South Africa to contribute to environmental plann [...] ing and conservation management in this floristically unique region. In this paper, we aim to provide an update on the development of the NVD since it was last described, near its inception, more than a decade ago. The NVD was developed using the Turboveg software environment, and currently comprises 46 697 vegetation plots (relevés) sharing 11 690 plant taxa and containing 968 943 species occurrence records. The NVD was primarily founded to serve vegetation classification and mapping goals but soon became recognised as an important tool in conservation assessment and target setting. The NVD has directly helped produce the National Vegetation Map, National Forest Type Classification, South African National Biodiversity Assessment and Forest Type Conservation Assessment. With further development of the NVD and more consistent handling of the legacy data (old data sets), the current limitations regarding certain types of application of the data should be significantly reduced. However, the use of the current NVD in multidisciplinary research has certainly not been fully explored. With the availability of new pools of well-trained vegetation surveyors, the NVD will continue to be purpose driven and serve the needs of biological survey in pursuit of sustainable use of the vegetation and flora resources of the southern African subcontinent.

Michael C., Rutherford; Ladislav, Mucina; Leslie W., Powrie.

251

European green lizard (Lacerta viridis) personalities: Linking behavioural types to ecologically relevant traits at different ontogenetic stages.  

Science.gov (United States)

Consistent individual differences within (animal personality) and across (behavioural syndrome) behaviours became well recognized during the past decade. Nevertheless, our knowledge about the evolutionary and developmental mechanisms behind the phenomena is still incomplete. Here, we explored if risk-taking and exploration were consistent and linked to different ecologically relevant traits in wild-caught adult male European green lizards (Lacerta viridis) and in their 2-3 weeks old laboratory-reared offspring. Both adults and juveniles displayed animal personality, consistency being higher in juveniles. We found correlation between risk-taking and exploration (suggestive of a behavioural syndrome) only in adults. Juveniles were more explorative than adults. Large or ectoparasite-free adult males were more explorative than small or parasitized males. Juvenile females tended to be more risk-taking than males. Behaviour of fathers and their offspring did not correlate. We conclude that European green lizards show high behavioural consistency and age is an important determinant of its strength and links to traits likely affecting fitness. PMID:25475912

Bajer, Katalin; Horváth, Gergely; Molnár, Orsolya; Török, János; Garamszegi, László Zsolt; Herczeg, Gábor

2015-02-01

252

Terrestrial Laser Scanning for Vegetation Sampling  

Directory of Open Access Journals (Sweden)

Full Text Available We developed new vegetation indices utilizing terrestrial laser scanning (TLS to quantify the three-dimensional spatial configuration of plant communities. These indices leverage the novelty of TLS data and rely on the spatially biased arrangement of a TLS point cloud. We calculated these indices from TLS data acquired within an existing long term manipulation of forest structure in Central Oregon, USA, and used these data to test for differences in vegetation structure. Results provided quantitative evidence of a significant difference in vegetation density due to thinning and burning, and a marginally significant difference in vegetation patchiness due to grazing. A comparison to traditional field sampling highlighted the novelty of the TLS based method. By creating a linkage between traditional field sampling and landscape ecology, these indices enable field investigations of fine-scale spatial patterns. Applications include experimental assessment, long-term monitoring, and habitat characterization.

Jeffrey J Richardson

2014-10-01

253

Biomass, composition and size structure of invertebrate communities associated to different types of aquatic vegetation during summer in Lago di Candia (Italy  

Directory of Open Access Journals (Sweden)

Full Text Available We compared the biomass, taxonomic composition, and size distribution of invertebrates associated to emergent (Schoenoplectus lacustris, submerged (Myriophyllum spicatum, and floating leaved (Trapa natans vegetation at two depths (surface and water column during summer in Lago di Candia, Italy. Invertebrate biomass was positively related to epiphyton biomass (Chl-a. M. spicatum supported higher invertebrate biomass per unit of plant weight than S. lacustris whereas T. natans was somewhat intermediate. Depth did not affect invertebrate biomass significatively. Surface sections of M. spicatum and T. natans supported invertebrate communities with similar taxonomic composition dominated by oligochaetes and ostracods. Large hirudineans and gastropods characterized the communities on the water column sections of M. spicatum. S. lacustris and the water column sections of T. natans (composed of stems and aquatic roots were supporting invertebrate communities dominated by copepod nauplii and lacking large organisms. Changes in aquatic vegetation in Lago di Candia following harvesting of T. natans and removal of submerged vegetation by the invasion of the rodent coypu (Miocastor coypus may affect the invertebrate biomass of its littoral zone.

Giuseppe MORABITO

2004-08-01

254

Using historic aerial photography and paleohydrologic techniques to assess long-term ecological response to two Montana dam removals.  

Science.gov (United States)

The restorative potential of dam removal on ecosystem function depends on the reversibility of dam effects and its operations. While dam removal is an established engineering practice, the need for an understanding of the ecological response remains. We used paleoflood hydrology, hydrologic modeling, and aerial photo interpretation to investigate the long-term ecologic responses to dam failure and breach. We investigated downstream geomorphic and vegetation responses to a dam failure (Pattengail Dam in 1927) and a controlled dam breach, which used natural sediment removal (Mystic Lake Dam in 1985). Our data showed vegetation responses indicative of channel and floodplain evolution at Pattengail. The size of the flood following the Pattengail dam failure initiated a series of channel adjustments and reworked over 19ha of floodplain downstream of the dam. In Mystic, we observed few flood stage indicators and a slight response in floodplain vegetation. We made several findings. (1) Dam removal effects on channel evolution and floodplain development depend on reach types and their responsiveness to flow regime change. (2) Ecologic response to dam removal depends on the sizes and timing of high flow events during and following removal. (3) Paleohydrology can be used to assess historic floods (>20 years). We see the utility of assessing the ecological responsiveness of a system to previous fluvial events or changes in flow regime. Informed about the character of a system based on its history, dam removal scientists can use these tools to set realistic restoration goals for removing a dam. PMID:19042079

Schmitz, Denine; Blank, Matt; Ammondt, Selita; Patten, Duncan T

2009-07-01

255

Vegetable of Slovene origin and consumers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Production of vegetable is decreasing constantly in Slovenia. From health point of view locally produced food is more recommendable, because it contains fewer residues of pesticides, more vitamins and has high quality. In my dissertation I presented state of agriculture in Slovenia. Above all I was interested in state and production of vegetables. I described different types of production of vegetable, from conventional to biological dynamic. I was interested in rules, laws and regulation...

Kokalj, Doris

2012-01-01

256

DEM modelling, vegetation characterization and mapping of aspen parkland rangeland using LIDAR data  

Science.gov (United States)

Detailed geographic information system (GIS) studies on plant ecology, animal behavior and soil hydrologic characteristics across spatially complex landscapes require an accurate digital elevation model (DEM). Following interpolation of last return LIDAR data and creation of a LIDAR-derived DEM, a series of 260 points, stratified by vegetation type, slope gradient and off-nadir distance, were ground-truthed using a total laser station, GPS, and 27 interconnected benchmarks. Despite an overall mean accuracy of +2 cm across 8 vegetation types, it created a RMSE (square root of the mean square error) of 1.21 m. DEM elevations were over-estimated within forested areas by an average of 20 cm with a RMSE of 1.05 m, under-estimated (-12 cm, RMSE = 1.36 m) within grasslands. Vegetation type had the greatest influence on DEM accuracy, while off-nadir distance (P = 0.48) and slope gradient (P = 0.49) did not influence DEM accuracy; however, the latter factors did interact (P < 0.10) to effect accuracy. Vegetation spatial structure (i.e., physiognomy) including plant height, cover, and vertical or horizontal heterogeneity, are important factors influencing biodiversity. Vegetation over and understory were sampled for height, canopy cover, and tree or shrub density within 120 field plots, evenly stratified by vegetation formation (grassland, shrubland, and aspen forest). Results indicated that LIDAR data could be used for estimating the maximum height, cover, and density, of both closed and semi-open stands of aspen (P < 0.001). However, LIDAR data could not be used to assess understory (<1.5 m) height within aspen stands, nor grass height and cover. Recognition and mapping of vegetation types are important for rangelands as they provide a basis for the development and evaluation of management policies and actions. In this study, LIDAR data were found to be superior to digital classification schedules for their mapping accuracy in aspen forest and grassland, but not shrubland. No single classification schedule created a high classification accuracy map for all types; however, the integration of LIDAR data and digital images achieved maps with corresponding overall accuracies of 91% and 83.9% with 3 and 8 classes of vegetation.

Su, Guangquan

257

Effect of harvest at different times of day on the physical and chemical characteristics of vegetable-type soybean Efeito da colheita em diferentes horários do dia sobre as características químicas e físicas de soja tipo hortaliça  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The objective of this study was to evaluate the effect of harvest at different times of day on the chemical and physical characteristics of vegetable-type soybean BRS 267 cultivar, harvested at the R6 stage (seed development) and to compare it with that on the grains harvested at the R8 stage (maturation). The pods of the BRS 267 cultivar were harvested at the R6 stage (at 8:00 AM, 12:00 AM, and 6:00 PM), the color parameters were evaluated, and the grains were analyzed for chemical compositi...

Andréia Cristina Santana; Mercedes Concórdia Carrão-Panizzi; José Marcos Gontijo Mandarino; Rodrigo Santos Leite; Josemeyre Bonifácio da Silva; Elza Iouko Ida

2012-01-01

258

Bacterial Ecology  

DEFF Research Database (Denmark)

Bacterial ecology is concerned with the interactions between bacteria and their biological and nonbiological environments and with the role of bacteria in biogeochemical element cycling. Many fundamental properties of bacteria are consequences of their small size. Thus, they can efficiently exploit very dilute solutions of organic matter and their potential growth rates are very high. Bacteria do not have a cytoskeleton and they are covered by a rigid cells wall. Therefore they can only take up dissolved low-molecular-weight compounds from their surroundings; when bacteria exploit polymeric compounds these must first be undergo extracellular hydrolysis. Bacteria have a great diversity with respect to types of metabolism that far exceeds the metabolic repertoire of eukaryotic organisms. Bacteria play a fundamental role in the biosphere and certain key processes such as, for example, the production and oxidation of methane, nitrate reduction and fixation of atmospheric nitrogen are exclusively carried out by different groups of bacteria. Some bacterial species – ‘extremophiles’ – thrive in extreme environments in which no eukaryotic organisms can survive with respect to temperature, salinity or pH. Key Concepts:Key Concepts: * Fundamental properties of bacteria are related to their small size and lack of cytoskeleton. * Bacteria display a great diversity in types of metabolism. * Bacteria play a key role in the biosphere in terms of transfer of matter and energy. * A number of fundamental biogeochemical processes are carried exclusively by bacteria. * Bacteria play an important role in all types of habitats including some that cannot support eukaryotic life.

Fenchel, Tom

2011-01-01

259

Biodiversity analysis of vegetation on the Nevada Test Site  

International Nuclear Information System (INIS)

The Nevada Test Site (NTS), located in south-central Nevada, encompasses approximately 3,500 square kilometers and straddles two major North American deserts, Mojave and Great Basin. Transitional areas between the two desert types have been created by gradients in elevation, precipitation, temperature, and soils. From 1996 to 1998, more than 1,500 ecological landform units were sampled at the NTS for numerous biotic and abiotic parameters. The data provide a basis for spatial evaluations of biodiversity over landscape scales at the NTS. Biodiversity maps (species richness vs. species abundance) have been produced. Differences in biodiversity among ecoregions and vegetation alliances are presented. Spatial distribution maps of species' presence and abundance provide evidence of where transition zones occur and the resulting impact on biodiversity. The influences of abiotic factors, such as elevation, soil, and precipitation, on biodiversity are assessed

260

Restoration of minerotrophic vegetation within an Irish raised bog soak system.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Clara Bog is an oceanic raised bog of international ecological importance located in central Ireland. The occurrence of soak systems (areas of mesotrophic/minerotrophic vegetation within acid bog) adds greatly to the scientific interest of Clara Bog. Recent research into the vegetation history of a soak system on Clara Bog known as Lough Roe indicates that major vegetation changes have occurred within the soak over the past century. Vegetation communities were classified and mapped on three d...

Crushell, P. H.; Schouten, M. G. C.; Smolders, A. J. P.; Roelofs, J. G. M.; Giller, P. S.

2006-01-01

 
 
 
 
261

[Comparison of GIMMS and MODIS normalized vegetation index composite data for Qing-Hai-Tibet Plateau].  

Science.gov (United States)

Consistent NDVI time series are basic and prerequisite in long-term monitoring of land surface properties. Advanced very high resolution radiometer (AVHRR) measurements provide the longest records of continuous global satellite measurements sensitive to live green vegetation, and moderate resolution imaging spectroradiometer (MODIS) is more recent typical with high spatial and temporal resolution. Understanding the relationship between the AVHRR-derived NDVI and MODIS NDVI is critical to continued long-term monitoring of ecological resources. NDVI time series acquired by the global inventory modeling and mapping studies (GIMMS) and Terra MODIS were compared over the same time periods from 2000 to 2006 at four scales of Qinghai-Tibet Plateau (whole region, sub-region, biome and pixel) to assess the level of agreement in terms of absolute values and dynamic change by independently assessing the performance of GIMMS and MODIS NDVI and using 495 Landsat samples of 20 km x20 km covering major land cover type. High correlations existed between the two datasets at the four scales, indicating their mostly equal capability of capturing seasonal and monthly phenological variations (mostly at 0. 001 significance level). Simi- larities of the two datasets differed significantly among different vegetation types. The relative low correlation coefficients and large difference of NDVI value between the two datasets were found among dense vegetation types including broadleaf forest and needleleaf forest, yet the correlations were strong and the deviations were small in more homogeneous vegetation types, such as meadow, steppe and crop. 82% of study area was characterized by strong consistency between GIMMS and MODIS NDVI at pixel scale. In the Landsat NDVI vs. GIMMS and MODIS NDVI comparison of absolute values, the MODIS NDVI performed slightly better than GIMMS NDVI, whereas in the comparison of temporal change values, the GIMMS data set performed best. Similar with comparison results of GIMMS and MODIS NDVI, the consistency across the three datasets was clearly different among various vegetation types. In dynamic changes, differences between Landsat and MODIS NDVI were smaller than Landsat NDVI vs. GIMMS NDVI for forest, but Landsat and GIMMS NDVI agreed better for grass and crop. The results suggested that spatial patterns and dynamic trends of GIMMS NDVI were found to be in overall acceptable agreement with MODIS NDVI. It might be feasible to successfully integrate historical GIMMS and more recent MODIS NDVI to provide continuity of NDVI products. The accuracy of merging AVHRR historical data recorded with more modern MODIS NDVI data strongly depends on vegetation type, season and phenological period, and spatial scale. The integration of the two datasets for needleleaf forest, broadleaf forest, and for all vegetation types in the phenological transition periods in spring and autumn should be treated with caution. PMID:24830255

Du, Jia-Qiang; Shu, Jian-Min; Wang, Yue-Hui; Li, Ying-Chang; Zhang, Lin-Bo; Guo, Yang

2014-02-01

262

Contribution to the Ecology of the Deltaic Mediterranean Coast, Egypt  

Directory of Open Access Journals (Sweden)

Full Text Available The ecology of the western section of the Deltaic Mediterranean Coast of Egypt provides a quantitative assessment of the vegetation structure, the main soil characteristics and an evaluation of the relationships between the recognized vegetation groups and environmental attributes. Vegetation and soil were sampled in 75 stands representing the physiographic variation and/or different habitat types in the study area. Relative values of frequency, density and cover for each perennial and the annuals were also recorded. The soil characteristics of collected samples were determined for each stand. 75 sampled stands were classified according to multivariate analysis (classification & ordination into nine defined vegetational groups, namely: group A dominated by Alhagi graecorum Boiss., group B codominated by Phragmites australis (Cav. Trin. ex Steud. and Halocnemum strobilaceum (Pallas M. Bieb, group C dominated by Arthrocnemum macrostachyum (Moric. Moris et Delponte, group D dominated by Sporobolus spicatus (Vahl Kunth, groups E & F dominated by Sporobolus viriginicus (L. Kunth, group G dominated by Stipagrostis scoparia (Trin. & Rupr. De Winter, group H dominated by Echium sericeum Vahl and group I dominated by Lotus creticus L. Detrended Correspondence Analysis (DCA and Canonical Correspondence Analysis (CCA were used to evaluate vegetation-environment relationships. Moisture content, soil texture (coarse & fine sand, soil reaction (pH, calcium carbonate content, sodium adsorption ratio, extractable cations (calcium and potassium and electrical conductivity were highly correlated with the first and second ordination axes. Thus, these soil variables seem to be the main important environmental factors affecting the distribution of vegetation in the study area.

Ibrahim A. Mashaly

2001-01-01

263

Lead and zinc contamination of vegetation in the southern Pennines  

Energy Technology Data Exchange (ETDEWEB)

Three types of heavy metal tolerant vegetation occurring on the spoil heaps in the Pennines are described sociologically and ecologically and their distribution in the Peak District National Park mapped. Concentrations of lead and zinc extractable from soils by acetic acid are recorded, as are total values for these two heavy metals in the tissues of the main component phanerogams and cryptogams of the vegetation. The range of values for zinc in plant tissues are uniformly higher than those for lead. Concentrations of lead accumulated by these plants are higher than those reported for the accumulation of atmospheric lead. The differences in heavy metal absorption, retention and excretion between ectohydric and myxohydric mosses are shown to be quite distinct. The heavy metals are excreted in the former type and form a crust in periods of drought with up to 6% lead and 1.5% zinc content, while, in the latter, the metals tend to be located mainly in the older growth at the base of the moss carpets. The concentrations of the two metal ions in two Peak District rivers proved to be less than 1 ppm in all samples.

Shimwell, D.W.; Laurie, A.E.

1972-01-01

264

The Effect of CO2 Stabilization on Uptake Rates in Land and Ocean Sinks as a Function of Ocean Circulation, Vegetation Type, and CO2 Fertilization  

Science.gov (United States)

In order to mitigate effects of climate change, governing entities need to limit carbon dioxide (CO2) in the atmosphere to a concentration yet to be determined. To assist policymakers, this experiment tested selected sensitivities of the land and ocean sinks to a proposed CO2 stabilization scenario of 600 parts per million by 2100. Sensitivities evaluated were the effect of CO2 fertilization on vegetation, the effect of long-lived forests vs. short-lived steppes, and the effect of various ocean circulation rates. All simulations were done with Tethys, a four-box earth-systems model consisting of a vegetation-soil reservoir, ocean, atmosphere, and emissions source. Results are generated through a series of equations written in IDL code, parameterized to simulate key processes in the climate-carbon cycle. Results generated in response to ocean and land sink behavior included peak allowable emissions, CO2 uptake rates in a reservoir, and the maximum amount of allowable emissions to maintain concentrations at 600 ppm. Tethys predicted that the rate of carbon uptake in the oceans will decrease with an increase in circulation time, and that the vegetation sink will cease to exist soon after atmospheric CO2 is stabilized. Simulations suggest that grasslands will absorb more CO2 than forests, a result that indicates a flaw in the model. The carbon cycle sensitivities tested in this experiment determine how much humans can emit and how quickly emissions need to be reduced to meet stabilization goals. Future sink behavior should be incorporated into any plan that seeks to stabilize atmospheric CO2.

Searles, Z. A.

2007-12-01

265

Modelling the Ecological Vulnerability to Forest Fires in Mediterranean Ecosystems Using Geographic Information Technologies  

Science.gov (United States)

Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model's predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model's predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model's performance is satisfactory when applied to the three selected vegetation types.

Duguy, Beatriz; Alloza, José Antonio; Baeza, M. Jaime; De la Riva, Juan; Echeverría, Maite; Ibarra, Paloma; Llovet, Juan; Cabello, Fernando Pérez; Rovira, Pere; Vallejo, Ramon V.

2012-12-01

266

Modelling the ecological vulnerability to forest fires in mediterranean ecosystems using geographic information technologies.  

Science.gov (United States)

Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model's predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model's predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model's performance is satisfactory when applied to the three selected vegetation types. PMID:23052472

Duguy, Beatriz; Alloza, José Antonio; Baeza, M Jaime; De la Riva, Juan; Echeverría, Maite; Ibarra, Paloma; Llovet, Juan; Cabello, Fernando Pérez; Rovira, Pere; Vallejo, Ramon V

2012-12-01

267

ASSESMENT OF ECOLOGICAL STATUS OF DANUBE DELTA LAKES USING INDICATOR MACROPHYTES SPECIES  

Directory of Open Access Journals (Sweden)

Full Text Available Implementation of European Water Framework Directive (WFD legislation requires valuation of chemical and ecological status of surface water bodies. One of the biological indicators prescribes for such assessment is aquatic macrophytes taxonomic composition and abundance. In many member states the trophic status of the lakes is asses by calculating trophic index. This paper show the results of applying Schaumburg reference index for 39 water bodies in Danube Delta . Total P, secchi depth, connectivity and substrate type were the main environmental variables calculated versus index values. As lakes differs little in tot. P content, distribution of aquatic vegetation seems to be mainly determined by connectivity type, substrate and lake morphology.

J. HANGANU

2008-01-01

268

Weed Identification and Control in Vegetable Crops.  

Science.gov (United States)

This agriculture extension service publication from Pennsylvania State University examines weed control and identification in vegetable crops. Contents include: (1) Types of weeds; (2) Reducing losses caused by weeds, general control methods and home garden weed control; (3) How herbicides are used; (4) Specific weeds in vegetable plantings; and…

Ferretti, Peter A., Comp.

269

Ecological Biology (Program Description)  

Science.gov (United States)

... in the following areas. Ecology: Supports studies of community ecology and population interactions ... 7) co-evolution, and (8) chemical ecology. Ecology particularly encourages studies that reveal ...

270

Environmental Impact of Flooding in the Main (Smallwood Reservoir of the Churchill Falls Power Plant, Labrador, Canada. I. Background and Descriptions of Flooded Conditions Related to Vegetation and Land Cover Types  

Directory of Open Access Journals (Sweden)

Full Text Available This paper, the first in a series provides the background of the project, reports on the early phases of construction with the descriptions of the pre and post flooded conditions related to vegetation and land cover types surrounding the reservoir. Currently there are plans to develop the so called “Lower Churchill Area” by establishing new power plants at Gull Island and at Muskrat Falls with associated reservoirs. These new plants would use the discharged water of the plant from Churchill Falls and the additional water collected from some of the Churchill River Basin. The information provided by these papers could have relevance to the environmental evaluation of these new developments. The Churchill Falls Hydro Project (called the “Upper Churchill Development” in Labrador, Canada, was initiated in the late 1960s and the 5428-MW hydro generating plant constructed was then among the largest in the world. At that time, in general, not much attention was paid to the impact of such development on the flooding of vegetation especially forest stands. Both forested and un-forested terrestrial vegetation types were flooded (244 915 ha. Some islands were created and in addition portions of existing areas were flooded to form islands (74 075 ha in the Main (Smallwood Reservoir area. The flooded area of forest and un-forested land in the reservoir is 77% while the islands is 23 percent. The percentages of forested and un-forested areas lost to flooding are 64% and 36% respectively. The percent of commercial forests lost to flooding is approximately 1% and the non-commerci- al forests is 99% (with a total volume of approximately 10 million cubic meters of wood.

Bruce A. Roberts

2011-03-01

271

Estudos ecológicos com o feijoeiro (Phaseolus vulgaris L.): I - Efeitos da incorporação de massa vegetal ao solo, e do sombreamento parcial / Ecological studies with dry beans (Phaseolus vulgaris L.): I - effects of incorporating undecomposed vegetative matter in the soil and of partial shading of the plants  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Em ensaio iniciado em março de 1969, na Estação Experimental de Jundiaí, SP, foram estudados os efeitos da incorporação de massa vegetal, proveniente de leguminosas e de gramínea, e do sombreamento parcial, simulando o plantio consorciado com milho, na cultura do feijoeiro. Determinou-se para cultur [...] as "apleno sol" e "sombreada" a temperatura do solo a 2 e 10 cm de profundidade. Observou-se efeito favorável da incorporação de massa vegetal ao solo imediatamente antes do plantio do feijoeiro. Os tratamentos que receberam incorporação de massa vegetal produziram mais sementes de feijão, o que os torna estatisticamente superiores aos tratamentos que não receberam tal prática. Nessas mesmas condições o sombreamento parcial não interferiu na temperatura ambiente, nem na do solo, e tampouco na produção, que foi praticamente idêntica à do tratamento testemunha. Abstract in english In 1969 an experiment with dry beans was started at the Estação Experimental de Jundiaí (State of São Paulo) with the scope to study the effects of the incorporation in the soil of undecomposed vegetative matter, which sources were leguminous plants (Glycine wightii Verdc.) and grass (Melinis minuti [...] flora Béauv.), as well as of the partial shading of the plants. Soil temperatures were determined at depths of two and ten centimeters in all treatments. Air temperature was determined in plots with and without shading. The treatments which consisted in the incorporation of undecomposed vegetative matter at all times produced higher yields than those with shading and control. There was no significant difference in grain yields of treatments with leguminous plants and grass, as well as between shading and control. With incorporation of vegetative matter the variation of the temperature in the soil was a little lower than with shading or control.

Eduardo A., Bulisani; Shiro, Miyasaka; Luiz D' Artagnan de, Almeida; Hélio J., Scaranari; Hilton S., Pinto.

272

Estudos ecológicos com o feijoeiro (Phaseolus vulgaris L.: I - Efeitos da incorporação de massa vegetal ao solo, e do sombreamento parcial Ecological studies with dry beans (Phaseolus vulgaris L.: I - effects of incorporating undecomposed vegetative matter in the soil and of partial shading of the plants  

Directory of Open Access Journals (Sweden)

Full Text Available Em ensaio iniciado em março de 1969, na Estação Experimental de Jundiaí, SP, foram estudados os efeitos da incorporação de massa vegetal, proveniente de leguminosas e de gramínea, e do sombreamento parcial, simulando o plantio consorciado com milho, na cultura do feijoeiro. Determinou-se para culturas "apleno sol" e "sombreada" a temperatura do solo a 2 e 10 cm de profundidade. Observou-se efeito favorável da incorporação de massa vegetal ao solo imediatamente antes do plantio do feijoeiro. Os tratamentos que receberam incorporação de massa vegetal produziram mais sementes de feijão, o que os torna estatisticamente superiores aos tratamentos que não receberam tal prática. Nessas mesmas condições o sombreamento parcial não interferiu na temperatura ambiente, nem na do solo, e tampouco na produção, que foi praticamente idêntica à do tratamento testemunha.In 1969 an experiment with dry beans was started at the Estação Experimental de Jundiaí (State of São Paulo with the scope to study the effects of the incorporation in the soil of undecomposed vegetative matter, which sources were leguminous plants (Glycine wightii Verdc. and grass (Melinis minutiflora Béauv., as well as of the partial shading of the plants. Soil temperatures were determined at depths of two and ten centimeters in all treatments. Air temperature was determined in plots with and without shading. The treatments which consisted in the incorporation of undecomposed vegetative matter at all times produced higher yields than those with shading and control. There was no significant difference in grain yields of treatments with leguminous plants and grass, as well as between shading and control. With incorporation of vegetative matter the variation of the temperature in the soil was a little lower than with shading or control.

Eduardo A. Bulisani

1972-01-01

273

Airborne gamma-spectrometric detection and types of geochemical radioactive anomalies in Serbia and adjacent areas and their ecological importance  

International Nuclear Information System (INIS)

The territory of Serbia and adjacent areas is built up by many geological formations of diverse composition/age belonging to a few major geostructural units. Some of them may contain enrichments of radioactive elements may be risks (as sources of radioactivity) to the health of population. By the airborne gamma-spectrometric surveys, applied at a few localities in diverse geological units, zones of geochemically anomalous radio-activity were discovered, related to different geological-geochemical systems. The anomalies, defined by gamma-ray radioactivity, a total and specific ones (of K-40, and Bi-214 and Tl-208, as indicators of U and Th, respectively), differ in both geochemical types and environmental-health impacts. (author)

274

[Feasibility of monitoring karst standing conditions with vegetation spectra].  

Science.gov (United States)

Karst regions are typically ecological fragile zones constrained by geological setting, which resulted in high heterogeneity of vegetation standing conditions. The karst vegetation was featured with stone, dry and high calcium carbonate content growth conditions. Based on vegetation spectral analysis and canonical correspondence analysis (CCA), the present study aimed to examine the feasibility of using vegetation spectra to monitor the heterogeneous karst standing conditions. The results showed that there were significant differences between karst vegetation and non-karst vegetation within the spectral range of 1 300-2 500 nm reflectance and 400 - 680 nm first-derivative spectra. It was found that soil moisture and calcium carbonate contents had the most significant effects on vegetation spectral features in karst regions. Ordination diagrams of CCA could distinguish the differences of karst vegetation and non-karst vegetation. Our study demonstrates that vegetation spectra are highly related to karst standing conditions and it is feasible to monitor karst standing conditions with vegetation spectral features. PMID:23016347

Yue, Yue-Min; Wang, Ke-Lin; Xiong, Ying

2012-07-01

275

Mechanical Analyses for coupled Vegetation-Flow System  

Science.gov (United States)

Vegetation in riparian areas plays important roles in hydrology, geomorphology and ecology in local environment. Mechanical response of the aquatic vegetation to hydraulic forces and its impact on flow hydraulics have received considerable attention due to implications for flood control, habitat restoration, and water resources management. This study aims to advance understanding of the mechanical properties of in-stream vegetation including drag force, moment and stress. Dynamic changes of these properties under various flow conditions largely determine vegetation affected flow field and dynamic resistance with progressive bending, and hydraulic conditions for vegetation failure (rupture or wash-out) thus are critical for understanding the coupled vegetation-flow system. A new approach combining fluid and material mechanics is developed in this study to examine the behavior of both rigid and flexible vegetation. The major advantage of this approach is its capability to treat large deflection (bending) of plants and associated changes of mechanical properties in both vegetation and flow. Starting from simple emergent vegetation, both static and dynamic formulations of the problem are presented and the solutions are compared. Results show the dynamic behavior of a simplified system mimicking complex and real systems, implying the approach is able to disclose the physical essence of the coupled system. The approach is extended to complex vegetation under both submerged and emergent conditions using more realistic representation of biomechanical properties for vegetation.

Chen, L.; Acharya, K.; Stone, M.

2010-12-01

276

Relationship between fire regime and vegetation symphenological timing in Sardinia  

Directory of Open Access Journals (Sweden)

Full Text Available Fire is a basic ecological factor that contributes to determine vegetation biodiversity and dynamics in time and space. Fuel characteristics play an essential role in fire ignition and propagation; for instance fuel availability and flammability are closely related to the coarse-scale vegetation phenological trends that directly affect wildfire distribution in time and space. In this perspective, the annual NDVI profiles derived from high temporal resolution satellite images like SPOT Vegetation represent an effective tool for monitoring plant seasonal dynamics at the landscape scale. The objective of this study consists in relating the wildfire regime in Sardinia during 2000-2004 with the remotely sensed phenological parameters of the vegetation, segmented according to potential natural vegetation characteristics. The results of our study highlight a good correspondence between the NDVI temporal dynamics of the potential natural vegetation of Sardinia and the corresponding fires regime characteristics.

Carlo Ricotta

2008-01-01

277

SRS ecology: Environmental information document  

International Nuclear Information System (INIS)

The purpose of this Document is to provide a source of ecological information based on the exiting knowledge gained from research conducted at the Savannah River Site. This document provides a summary and synthesis of ecological research in the three main ecosystem types found at SRS and information on the threatened and endangered species residing there

278

SRS ecology: Environmental information document  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this Document is to provide a source of ecological information based on the exiting knowledge gained from research conducted at the Savannah River Site. This document provides a summary and synthesis of ecological research in the three main ecosystem types found at SRS and information on the threatened and endangered species residing there.

Wike, L.D.; Shipley, R.W.; Bowers, J.A. [and others

1993-09-01

279

Ecological economics  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ecological economics is a recently developed field, which sees the economy as a subsystem of a larger finite global ecosystem. Ecological economists question the sustainability of the economy because of its environmental impacts and its material and energy requirements, and also because of the growth of population. Attempts at assigning money values to environmental services and losses, and attempts at correcting macroeconomic accounting, are part of ecological economics, but its main thrust ...

Marti?nez Alier, Joan

2001-01-01

280

Selected types of geotopes in the territory stricken by a storm in the vicinity of Tatranska Polianka  

International Nuclear Information System (INIS)

Aim of this paper is identification and characterization of selected types of representative geotopes in selected area affected by calamity (19 November 2004) around Tatranska Polianka. Lessons learned about the types geotopes try to bring a comprehensive view of the landscape system of selected area. In the long-term horizon they may form the basis for proposals for ecological optimization of spatial structure of vegetation in the territory of the Tatra National Park.

 
 
 
 
281

Cuantificación del carbono almacenado en formaciones vegetales amazónicas en "CICRA", Madre de Dios (Perú) / Quantification of the carbon storage in amazon vegetation types at "CICRA", Madre de Dios (Peru)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Peru | Language: Spanish Abstract in spanish La llanura amazónica peruana se caracteriza por la presencia de múltiples formaciones vegetales. Éstas cada vez reciben mayor impacto por actividades antropogénicas tales como la minería y tala. Todo esto, sumado al cambio climático global, genera desconcierto sobre el futuro de los bosques. La iden [...] tificación de los niveles de almacenamiento de carbono en áreas boscosas, y específicamente en cada formación vegetal, permitiría un mejor manejo de las zonas de conservación, así como identificar las áreas potenciales que servirían para el financiamiento de la absorción de carbono y otros servicios ambientales. El presente estudio fue desarrollado en la estación Biológica del Centro de Investigación y Capacitación Río Los Amigos (CICRA). En el CICRA se identificaron tres formaciones vegetales principales, el bosque de terraza, el bosque inundable y el aguajal. Siendo los bosques de terraza los de mayor extensión y mayor cantidad de carbono acumulado. Como resultado se valorizó la vegetación presente en el CICRA, en alrededor de 11 millones de dólares americanos. El ingreso a la oferta de los bonos de carbono promovería la conservación de los bosques. Abstract in english The Peruvian Amazon Basin is characterized by the presence of multiple vegetation types. They are being given great impact by human activities such as mining and, logging. All this, coupled with global climate change, creates confusion about the future of our forests. The identification of levels of [...] carbon storage in forested areas, and specifically in each vegetation type, would allow better management of conservation areas, and then identify potential areas that could serve to finance carbon sequestration and other environmental services. This study was conducted at the Biological Station for Research and Training Center Rio Los Amigos (CICRA, Spanish acronym). At the station three main formations were identified, alluvial terrace forests, flood terrace forests and Mauritia swamps. The alluvial terrace forest presents the most extensive area and the highest amount of carbon stored. As result, CICRA vegetations were valued at approx. 11 millions U.S. dollars. Admission to the supply of carbon credits could promote Amazon forest conservation.

Carlos, Martel; Lianka, Cairampoma.

2012-08-01

282

Arboreal Ant Assemblages Respond Differently to Food Source and Vegetation Physiognomies: a Study in the Brazilian Atlantic Rain Forest  

Directory of Open Access Journals (Sweden)

Full Text Available This study aimed to analyze assemblages of arboreal ants in different vegetation physiognomies within the Tropical Moist Forest (Atlantic Rain Forest domain. The study was carried out at the Michelin Ecological Reserve, State of Bahia, Northeast of Brazil. We used sardine (protein resource and honey (carbohydrate resource baits to collect ants foraging in three vegetation types: (1 preserved native forest, (2 forest in regeneration (capoeira with many invasive plants and (3 a mixed agroystem of rubber and cocoa tree plantation. We recorded 69 ant species attracted to the baits, 21 of them exclusive to honey bait and 25 exclusive to the sardine baits. The vegetation physiognomies preserved forest and rubber/cacao agrosystem showed higher species richness in relation to the forest in regeneration (capoeira, suggesting that rubber tree plantations can be a good matrix for the maintenance of some ant species typical of the forest matrix. The type of resource used is important for the structuring of the arboreal ant assemblages. The ants that were attracted to protein resources showed a guild composition that is more differentiated between vegetation types that of ants attracted to glucose resources.

Janete Jane Resende

2013-07-01

283

Diversidade e estimativas de riqueza de aranhas em quatro fitofisionomias na Serra do Cachimbo, Pará, Brasil / Spiders diversity and richness estimates in four vegetations types of Serra do Cachimbo, Pará, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Um inventário da fauna de aranhas foi realizado na Serra do Cachimbo, no Campo de Provas Brigadeiro Velloso, município de Novo Progresso, Pará. As coletas ocorreram em duas expedições, uma na estação seca (agosto e setembro de 2003) e outra na chuvosa (março e abril de 2004). Cada expedição contou c [...] om a participação de três coletores. O esforço de amostragem foi de 240 amostras, sendo 96 através de guarda-chuva entomológico e rede de varredura, 96 através de coleta manual noturna e 48 por triagem manual e extratores de Winkler. Foi comparada a diversidade de aranhas de quatro tipos de vegetação, Floresta Ombrófila Aberta, mata de galeria, áreas de Cerrado (Savana Arbórea) e de Campina. As coletas resultaram em um total de 4.990 indivíduos, dos quais 2.750 adultos. Foram identificadas 427 morfoespécies em 37 famílias, sendo as mais abundantes Theridiidae, Salticidae e Araneidae e as mais ricas em espécies Araneidae, Salticidae e Theridiidae. As espécies representadas por apenas um indivíduo somaram 40% do total e apenas duas ultrapassaram cem indivíduos. A curva de riqueza específica estimada (ACE) atingiu 614 espécies. A maior diversidade alfa (índice de Shannon-Wiener) foi encontrada em Floresta Ombrófila, seguida pela mata de galeria, Campina e Cerrado. Tais diferenças entre as vegetações podem ser explicadas devido a variações na complexidade da vegetação e na disponibilidade de microhábitats em cada fitofisionomia. Abstract in english An inventory of the spider fauna was carried out at Serra do Cachimbo, inside the "Campo de Provas Brigadeiro Velloso", municipality of Novo Progresso, state of Pará, Brazil. Two expeditions were made, during both dry (August and September, 2003) and wet (March and April, 2004) seasons. Three collec [...] tors participated in each expedition. The sampling effort, represented by 240 samples, was divided into the following methods: beating tray and sweeping net (96 samples); nocturnal hand search (96 samples) and concentrated litter sorted by a combination of hand search and Winkler extractors (48 samples). The spiders assemblages from four vegetation types (open rainforest, riparian forest, arboreal savanna and white sand vegetation) were compared. A total of 4,990 spiders were obtained, from which 2,750 adults, resulting in 427 morphospecies of 37 families. The most abundant families were Theridiidae, Salticidae, and Araneidae and the ones with more species were Salticidae, Araneidae, and Theridiidae. Singletons represented 40% of the total species richness and only two species presented more than 100 individuals. The estimated species richness curve produced by ACE reached 614 species. The highest alpha-diversity (Shannon-Wiener index) was observed in open rainforest, followed by riparian forest, white sand vegetation and arboreal savanna. These differences among the various vegetations can be explained by variations in vegetation complexity and micro-habitat availability in each vegetation type.

Janael, Ricetti; Alexandre B., Bonaldo.

2008-03-01

284

Diversidade e estimativas de riqueza de aranhas em quatro fitofisionomias na Serra do Cachimbo, Pará, Brasil Spiders diversity and richness estimates in four vegetations types of Serra do Cachimbo, Pará, Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available Um inventário da fauna de aranhas foi realizado na Serra do Cachimbo, no Campo de Provas Brigadeiro Velloso, município de Novo Progresso, Pará. As coletas ocorreram em duas expedições, uma na estação seca (agosto e setembro de 2003 e outra na chuvosa (março e abril de 2004. Cada expedição contou com a participação de três coletores. O esforço de amostragem foi de 240 amostras, sendo 96 através de guarda-chuva entomológico e rede de varredura, 96 através de coleta manual noturna e 48 por triagem manual e extratores de Winkler. Foi comparada a diversidade de aranhas de quatro tipos de vegetação, Floresta Ombrófila Aberta, mata de galeria, áreas de Cerrado (Savana Arbórea e de Campina. As coletas resultaram em um total de 4.990 indivíduos, dos quais 2.750 adultos. Foram identificadas 427 morfoespécies em 37 famílias, sendo as mais abundantes Theridiidae, Salticidae e Araneidae e as mais ricas em espécies Araneidae, Salticidae e Theridiidae. As espécies representadas por apenas um indivíduo somaram 40% do total e apenas duas ultrapassaram cem indivíduos. A curva de riqueza específica estimada (ACE atingiu 614 espécies. A maior diversidade alfa (índice de Shannon-Wiener foi encontrada em Floresta Ombrófila, seguida pela mata de galeria, Campina e Cerrado. Tais diferenças entre as vegetações podem ser explicadas devido a variações na complexidade da vegetação e na disponibilidade de microhábitats em cada fitofisionomia.An inventory of the spider fauna was carried out at Serra do Cachimbo, inside the "Campo de Provas Brigadeiro Velloso", municipality of Novo Progresso, state of Pará, Brazil. Two expeditions were made, during both dry (August and September, 2003 and wet (March and April, 2004 seasons. Three collectors participated in each expedition. The sampling effort, represented by 240 samples, was divided into the following methods: beating tray and sweeping net (96 samples; nocturnal hand search (96 samples and concentrated litter sorted by a combination of hand search and Winkler extractors (48 samples. The spiders assemblages from four vegetation types (open rainforest, riparian forest, arboreal savanna and white sand vegetation were compared. A total of 4,990 spiders were obtained, from which 2,750 adults, resulting in 427 morphospecies of 37 families. The most abundant families were Theridiidae, Salticidae, and Araneidae and the ones with more species were Salticidae, Araneidae, and Theridiidae. Singletons represented 40% of the total species richness and only two species presented more than 100 individuals. The estimated species richness curve produced by ACE reached 614 species. The highest alpha-diversity (Shannon-Wiener index was observed in open rainforest, followed by riparian forest, white sand vegetation and arboreal savanna. These differences among the various vegetations can be explained by variations in vegetation complexity and micro-habitat availability in each vegetation type.

Janael Ricetti

2008-03-01

285

Mutation breeding in vegetable crops  

International Nuclear Information System (INIS)

Vegetables breed by seeds and vegetative organs. In main vegetables, the differentiation of clopping types, the adoption of monoculture and year-round production and shipment are carried out, adapting to various socio-economic and cultivation conditions. Protected agriculture has advanced mainly for fruit vegetables, and the seeds for sale have become almost hybrid varieties. Reflecting the situation like this, the demand for breeding is diversified and characteristic, and the case of applying mutation breeding seems to be many. The present status of the mutation breeding of vegetables is not yet well under way, but about 40 raised varieties have been published in the world. The characters introduced by induced mutation and irradiation were compact form, harvesting aptitude, the forms and properties of stems and leaves, anti-lodging property, the size, form and uniformity of fruits, male sterility and so on. The radiation sources used were mostly gamma ray or X-ray, but sometimes, combined irradiation was used. As the results obtained in Japan, burdocks as an example of gamma ray irradiation to seeds, tomatoes as an example of inducing the compound resistance against disease injury and lettuces as an example of internal beta irradiation are reported. (Kako, I.)

286

Integrating field sampling, geostatistics and remote sensing to map wetland vegetation in the Pantanal, Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available Development of efficient methodologies for mapping wetland vegetation is of key importance to wetland conservation. Here we propose the integration of a number of statistical techniques, in particular cluster analysis, universal kriging and error propagation modelling, to integrate observations from remote sensing and field sampling for mapping vegetation communities and estimating uncertainty. The approach results in seven vegetation communities with a known floral composition that can be mapped over large areas using remotely sensed data. The relationship between remotely sensed data and vegetation patterns, captured in four factorial axes, were described using multiple linear regression models. There were then used in a universal kriging procedure to reduce the mapping uncertainty. Cross-validation procedures and Monte Carlo simulations were used to quantify the uncertainty in the resulting map. Cross-validation showed that accuracy in classification varies according with the community type, as a result of sampling density and configuration. A map of uncertainty derived from Monte Carlo simulations revealed significant spatial variation in classification, but this had little impact on the proportion and arrangement of the communities observed. These results suggested that mapping improvement could be achieved by increasing the number of field observations of those communities with a scattered and small patch size distribution; or by including a larger number of digital images as explanatory variables in the model. Comparison of the resulting plant community map with a flood duration map, revealed that flooding duration is an important driver of vegetation zonation. This mapping approach is able to integrate field point data and high-resolution remote-sensing images, providing a new basis to map wetland vegetation and allow its future application in habitat management, conservation assessment and long-term ecological monitoring in wetland landscapes.

J. Arieira

2011-03-01

287

Relationship between fire regime and vegetation symphenological timing in Sardinia  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Fire is a basic ecological factor that contributes to determine vegetation biodiversity and dynamics in time and space. Fuel characteristics play an essential role in fire ignition and propagation; for instance fuel availability and flammability are closely related to the coarse-scale vegetation phenological trends that directly affect wildfire distribution in time and space. In this perspective, the annual NDVI profiles derived from high temporal resolution satellite images like SPOT Vegetat...

Carlo Ricotta; Leonardo Rosati; Sofia Bajocco

2008-01-01

288

Characterization of vegetative insecticidal protein vip genes of Bacillus thuringiensis from Sichuan Basin in China.  

Science.gov (United States)

Vegetative insecticidal proteins (Vip), the second generation of insecticides, are produced during the vegetative growth stage of Bacillus thuringiensis (Bt). To perform a systematic study of vip genes in Bt strains from different ecological regions of Sichuan Basin, 1,789 soil samples were collected from this basin, which is situated in the western region of China. The basin has a complicated geomorphology and contains mountains, forests, highlands, hursts, and plains. A total of 2,134 Bt strains have been screened from the 1,789 soil samples. According to the results, three vip-type genes were found in this basin, namely the vip1, vip2, and vip3-type genes. Strains containing vip3-type genes were the most abundant in our collection (67.4%), followed by vip2-type genes (14.6%) and vip1-type genes (8.1%). The three types of vip genes were distributed in most of the regions, but E Mei Mountain and the Ba Lang Mountains only contained vip3 genes in environments with high elevation, low temperature, insufficient oxygen, and abundant snow. Moreover, five novel vip3 genes were found, and these Vip proteins were toxic for Chilo suppressalis. All the results mentioned above suggest that Sichuan Basin is a rich resource for vip genes. PMID:20963416

Yu, Xiumei; Zheng, Aiping; Zhu, Jun; Wang, Shiquan; Wang, Lingxia; Deng, Qiming; Li, Shuangcheng; Liu, Huainian; Li, Ping

2011-03-01

289

Ecological baseline studies in Los Alamos and Guaje Canyons County of Los Alamos, New Mexico. A two-year study  

Energy Technology Data Exchange (ETDEWEB)

During the summers of 1993 and 1994, the Biological Resource Evaluations Team (BRET) of the Environmental Protection Group (ESH-8) conducted baseline studies within two canyon systems, Los Alamos and Guaje Canyons. Biological data was collected within each canyon to provide background and baseline information for Ecological Risk models. Baseline studies included establishment of permanent vegetation plots within each canyon along the elevational gradient. Then, in association with the various vegetation types, surveys were conducted for ground dwelling insects, birds, and small mammals. The stream channels associated with the permanent vegetation plots were characterized and aquatic macroinvertebrates collected within the stream monthly throughout a six-month period. The Geographic Position System (GPS) in combination with ARC INFO was used to map the study areas. Considerable data was collected during these surveys and are summarized in individual chapters.

Foxx, T.S. [comp.

1995-11-01

290

Vegetation map (1994) of Setoda region, Hiroshima Prefecture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The vegetation map has a lot of information on regional environment. Vegetation type and its distribution often reflect the site condition and disturbances on the nature and social aspects. The vegetation map is important information not only to record the actual vegetation academically, but also to discuss the regional management plan for future. Setoda region, Hiroshima Prefecture is one of the most famous place for the citrus cultivation and tourism for historical facilities and inland sea...

??, ??; ??, ??; ?????, ????; ?????, ??????; Ikegami, Yoshiyuki; Nakagoshi, Nobukazu

2006-01-01

291

NATURAL VEGETATION OF BIHAR  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Naturally growing vegetation in any specified region is called natural vegetation which refers to the ground cover provided by plants to a particular taxis, life forms, structure, special extent or any other specific botanical or geographical characteristics.

Pandey, R. N.; Gautam Pandey

2014-01-01

292

Long-term vegetation monitoring for different habitats in floodplains  

Directory of Open Access Journals (Sweden)

Full Text Available A floodplain-restoration project along the Danube between Neuburg and Ingolstadt (Germany aims to bring back water and sediment dynamic to the floodplain. The accompanied long-term monitoring has to document the changes in biodiversity related to this new dynamics. Considerations on and results of the vegetation monitoring concept are documented in this paper. In a habitat rich ecosystem like a floodplain different habitats (alluvial forest, semi-aquatic/aquatic sites have different demands on the sampling methods. Therefore, different monitoring designs (preferential, random, systematic, stratified random and transect sampling are discussed and tested for their use in different habitat types of the floodplain. A stratified random sampling is chosen for the alluvial forest stands, as it guarantees an equal distribution of the monitoring plots along the main driving factors, i.e. influence of water. The parameters distance to barrage, ecological flooding, height above thalweg and distance to the new floodplain river are used for stratifying and the plots are placed randomly into these strata, resulting in 117 permanent plots. Due to small changes at the semi-aquatic/aquatic sites a transect sampling was chosen. Further, a rough stratification (channel bed, river bank adjacent floodplain was implemented, which was only possible after the start of the restoration project. To capture the small-scale changes due to the restoration measures on the vegetation, 99 additional plots completed the transect sampling. We conclude that hetereogenous study areas need different monitoring approaches, but, later on, a joint analysis must be possible.

LANG Petra

2014-03-01

293

Seasonal dynamics of vegetation after timber production in forest Babske  

International Nuclear Information System (INIS)

In this contribution we have summarized the results of research a season dynamic of vegetation which was realized in the locality of the Bab forest (village Velky Bab, Nitra loess upland) in the vegetative period of 2013. The Bab forest is a lowland oak-hornbeam forest in an intensively exploited agricultural country. This forest is the remnant of formerly larger indigenous forest complexes. The Bab forest represents a type of indigenous vegetation in this area. Specifically, this contribution is focused on the evaluation and comparison season dynamic of vegetation on two types of outposts - clear-cuts and forest vegetation. (author)

294

Ecological Footprint Calculators  

Science.gov (United States)

This website contains interactive calculators for determining various environmental impacts. The site includes more than 15 different calculators to determine greenhouse gas emissions, ecological footprints, electricity pollution, air travel pollution, commuting costs, appliance costs, pollution prevention and more. These calculators can be used for computer-based classroom activities or to enable students to see which types of activities have the greatest environmental impact.

EcoBusinessLinks

295

The relative importance of climate and vegetation properties on patterns of North American breeding bird species richness  

Science.gov (United States)

Recent advances in remote sensing and ecological modeling warrant a timely and robust investigation of the ecological variables that underlie large-scale patterns of breeding bird species richness, particularly in the context of intensifying land use and climate change. Our objective was to address this need using an array of bioclimatic and remotely sensed data sets representing vegetation properties and structure, and other aspects of the physical environment. We first build models of bird species richness across breeding bird survey (BBS) routes, and then spatially predict richness across the coterminous US at moderately high spatial resolution (1 km). Predictor variables were derived from various sources and maps of species richness were generated for four groups (guilds) of birds with different breeding habitat affiliation (forest, grassland, open woodland, scrub/shrub), as well as all guilds combined. Predictions of forest bird distributions were strong (R2 = 0.85), followed by grassland (0.76), scrub/shrub (0.63) and open woodland (0.60) species. Vegetation properties were generally the strongest determinants of species richness, whereas bioclimatic and lidar-derived vertical structure metrics were of variable importance and dependent upon the guild type. Environmental variables (climate and the physical environment) were also frequently selected predictors, but canopy structure variables were not as important as expected based on more local to regional scale studies. Relatively sparse sampling of canopy structure metrics from the satellite lidar sensor may have reduced their importance relative to other predictor variables across the study domain. We discuss these results in the context of the ecological drivers of species richness patterns, the spatial scale of bird diversity analyses, and the potential of next generation space-borne lidar systems relevant to vegetation and ecosystem studies. This study strengthens current understanding of bird species-climate-vegetation relationships, which could be further advanced with improved canopy structure information across spatial scales.

Goetz, Scott J.; Sun, Mindy; Zolkos, Scott; Hansen, Andy; Dubayah, Ralph

2014-03-01

296

The Grassland vegetation of Platberg, eastern Free State, South Africa  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english Platberg is an inselberg that presents a refuge for indigenous plants and animals. Uncontrolled human access to this area threatens this sensitive ecosystem. The vegetation of Platberg was investigated to obtain an inventory of the different plant species and communities present in this area. A hier [...] archical classification, a description and an ecological interpretation of the grassland communities of Platberg are presented. A total of 169 sample plots were placed on a stratified random basis within the study area. From a TWINSPAN classification a total of 27 different plant communities, which can be grouped into two major community types, nine communities, 18 sub-communities and six variants, were identified. A significant difference in species richness was found between the two major communities, with the higher-altitude communities having a higher species richness than the communities on the lower-lying slopes. A total of 26 endemic or near endemic Drakensberg Alpine Centre species were recorded. CONSERVATION IMPLICATIONS: Anthropogenic influences are felt globally on ecosystems. Highaltitude habitats and organisms will be affected first. Inselbergs have high levels of endemic organisms and are reservoirs and refugia for unique genetic material. This grassland plant community survey of Platberg provides valuable information on inselberg ecology for conservation planning.

Robert F., Brand; Leslie R., Brown; Pieter J., du Preez.

297

Principal vegetation types in a natural area close to the city of Rome as observed by ERS-1 SAR and Landsat TM  

Science.gov (United States)

The identification of plant communities in natural areas is fundamental to many applications. Among these are conservation and management of natural resources, production of thematic maps, and monitoring of relevant phenomena such as expansion of built-up areas and loss of grazing and cultivated lands. Multi-temporal radiometric characteristics as derived from ERS- 1 SAR and Landsat TM images have been analyzed for an area, located 30 km NW of Rome, which was studied by extensive ground surveys. The purpose of this study was to compare the information content of SAR images and Landsat TM bands analyzed together with topographical data, such as elevation, slope, and aspect, in order to develop an efficient classification methodology. Prior to classification, SAR images were corrected for the effect of scanning angle. Homogeneously vegetated areas found at different angle in the images allowed evaluation of the efficiency of this method. Canonical variable analysis was used to compare SAR and TM data in combination with topographic variables. After that, all the variables available were selected by a stepwise discriminant analysis for classification purposes. The variables considered in the model were used for the classification of test areas with an algorithm of linear discriminant analysis.

Attorre, Fabio; Manes, Fausto; Abbate, Giulia; Borfecchia, Flavio; Della Rocca, Antonio B.; Marchetti, Marco

1995-11-01

298

Satellite Ecology (SATECO)-linking ecology, remote sensing and micrometeorology, from plot to regional scale, for the study of ecosystem structure and function.  

Science.gov (United States)

There is a growing requirement for ecosystem science to help inform a deeper understanding of the effects of global climate change and land use change on terrestrial ecosystem structure and function, from small area (plot) to landscape, regional and global scales. To meet these requirements, ecologists have investigated plant growth and carbon cycling processes at plot scale, using biometric methods to measure plant carbon accumulation, and gas exchange (chamber) methods to measure soil respiration. Also at the plot scale, micrometeorologists have attempted to measure canopy- or ecosystem-scale CO(2) flux by the eddy covariance technique, which reveals diurnal, seasonal and annual cycles. Mathematical models play an important role in integrating ecological and micrometeorological processes into ecosystem scales, which are further useful in interpreting time-accumulated information derived from biometric methods by comparing with CO(2) flux measurements. For a spatial scaling of such plot-level understanding, remote sensing via satellite is used to measure land use/vegetation type distribution and temporal changes in ecosystem structures such as leaf area index. However, to better utilise such data, there is still a need for investigations that consider the structure and function of ecosystems and their processes, especially in mountainous areas characterized by complex terrain and a mosaic distribution of vegetation. For this purpose, we have established a new interdisciplinary approach named 'Satellite Ecology', which aims to link ecology, remote sensing and micrometeorology to facilitate the study of ecosystem function, at the plot, landscape, and regional scale. PMID:18958540

Muraoka, Hiroyuki; Koizumi, Hiroshi

2009-01-01

299

Combined assessment and regulation on ecological land use and water demand of the river system: a case study in Luanhe River, North China  

Directory of Open Access Journals (Sweden)

Full Text Available With economic and social development, ecological water and land use of the river system were seriously misappropriated, which resulted in overall degradation of the river systems. In this study, theoretical and technical frameworks of regionalisation on the eco-environmental function of the river systems were preliminarily formulated. According to the river eco-environmental functions, Luanhe River was regionalised into four types of first-class functional areas, i.e., ecological preservation areas, habitat restoration areas, ecological buffer areas and development and utilisation areas. Combined with the main functions of all functional areas, ecological land use of the river system in Luanhe River was assessed and planned. The total area of basic ecological land use was 876.98 km2; that of restrictive ecological land use was 1745.52 km2; that of ecological land use of the river system returned from farmland was 284.25 km2; and that returned from construction land was 17.35 km2. Combined with prototype observation experiments, the average minimum ecological flow of mainstreams in upper and middle reaches of the Luanhe River was 4.896 m3 s?1 with the habitat method. The evaporation and seepage consumption of the river system in Luanhe River and vegetation consumption in riparian zones were about 133 million m3 and 145 million m3 per year, respectively. Downwards from the Panjiakou-Daheiting Reservoir system, the mainstream of the Luanhe River was the crucial reach for regulation on instream ecological water use. It was required to speed up ecological land use planning of the river system and strengthen the regulation of ecological water use in important lower reaches of the Luanhe River under the condition of competitive water demand.

D. H. Yan

2011-10-01

300

Evaluating ecological monitoring systems on Mabula Game Reserve, Limpopo, South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ecological monitoring is an integral part of the ecological active adaptive management of wildlife reserves. The present study was conducted as an initial trial of a holistic ecological monitoring programme for Mabula Game Reserve using three existing survey methods. The information gained after each monitoring period and relevant management decisions are: Large herbivore monitoring: This monitoring system gave specific information on which vegetation community...

Smallwood, Samuel

2010-01-01

 
 
 
 
301

Radiocaesium in reindeer in relation to ground deposition, levels in vegetation, season and diet  

International Nuclear Information System (INIS)

After the Chernobyl accident, reindeer pastures in Fennoscandia were contaminated with radioactive material (mainly 137Cs). There were large geographical variations in contamination of reindeer and in apparent transfer of 137Cs from ground and vegetation to reindeer. There could be several reasons for the observed differences between areas. This work aims at collecting basic data on 137Cs activity concentrations in soil, vegetation and reindeer and constructing a model to describe the transfer of radiocaesium to reindeer over time. Field data on 137Cs in soil and vegetation has been collected during two years from one reindeer herding district (Jiingevaerie) in central Sweden. Data on 137Cs in reindeer is available from the same area from 1986 to 1998. The collected data, and data from earlier investigations, has been put in a simple dynamic model, taking into account ground deposition, initial transfer of 137Cs from fallout to different types of vegetation and long term change of 137Cs in vegetation as well as food intake, diet composition, absorption and biological half-time of 137Cs in reindeer. The ground contamination of 137Cs was 9 441 Bq/m2, at average, within reindeer pastures used during the summer period and 22 629 Bq/m2 within the areas used in wintertime. The relation between ground contamination and vegetation differed very much between and vegetation differed very much between sampling sites but were generally higher for lichens (however, not statistically significant) and fungi (significant). The relation between ground contamination and reindeer (Tag) counted back to 1986 with the observed effective ecological half-time (tef = 3. 6 years), was 0. 14 m2/kg for the season August-September and 0. 69 and 0. 66 m2/kg for the seasons October-December and January-April, respectively. Three simulations of 137Cs in reindeer over 12 years were made with the constructed model and simulated values were compared to observed activity concentrations of 137Cs in reindeer from 1986 to 1998. The simulated curves followed the same pattern as observed values but were slightly high for the summer period. Two simulations (a and c) gave low values for the winter period, while one simulation (b) did not differ significantly from values observed during the winter period. More data need to be collected, especially on relation between ground contamination and contamination of vegetation and long term change of 137Cs in vegetation, to get better input data for the model. The variation in diet, and factors that govern changes in diet, also need to be more thoroughly investigated

302

Integrating field sampling, spatial statistics and remote sensing to map wetland vegetation in the Pantanal, Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available To improve the protection of wetlands, it is imperative to have a thorough understanding of their structuring elements and of the identification of efficient methods to describe and monitor them. This article uses sophisticated statistical classification, interpolation and error propagation techniques, in order to describe vegetation spatial patterns, map plant community distribution and evaluate the capability of statistical approaches to produce high-quality vegetation maps. The approach results in seven vegetation communities with a known floral composition that can be mapped over large areas using remotely sensed data. The relations between remotely sensing data and vegetation patterns, captured in four factorial axes, were formalized mathematically in multiple linear regression models and used in a universal kriging procedure to reduce the uncertainty in mapped communities. Universal kriging has shown to be a valuable interpolation technique because parts of vegetation variability not explained by the images could be modeled as spatially correlated residuals, increasing prediction accuracy. Differences in spatial dependence of the vegetation gradients evidenced the multi-scale nature of vegetation communities. Cross validation procedures and Monte Carlo simulations were used to quantify the uncertainty in the resulting map. Cross-validation showed that accuracy in classification varies according with the community type, as a result of sampling density and configuration. A map of uncertainty resulted from Monte Carlo simulations displayed the spatial variation in classification accuracy, showing that the quality of classification varies spatially, even though the proportion and arrangement of communities observed in the original map is preserved to a great extent. These results suggested that mapping improvement could be achieved by increasing the number of field observations of those communities with a scattered and small patch size distribution; or by including new digital images as explanatory variables in the model. By comparing the resulting plant community map with a flood duration map, we verified that flooding duration is an important driver of vegetation zonation. We discuss our study in the context of developing a mapping approach that is able to integrate field point data and high-resolution remote sensing images, providing new basis to map wetland vegetation and allowing its future application in habitat management, conservation assessment and long-term ecological monitoring in wetland landscapes.

J. Arieira

2010-09-01

303

LANDSCAPE BIODIVERSITY CHANGES IN FOREST VEGETATION AND THE CASE STUDY OF THE LAVAZ  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Italian CONECOFOR programme of forest monitoring inserted in 2004 the study of “landscape biodiversity” because a forest is not only an ecosystem, it is –first of all- a landscape. The Biological Integrated School of Landscape Ecology, widening the concept of landscape, is able to elaborate a new methodology of vegetation survey (LaBISV) based on ecological parameters. This methodology allows to study the changes in forest vegetation referred both to landscap...

Giglio, E.; Ingegnoli, V.

2008-01-01

304

Composição florística das formações vegetais sobre uma turfeira topotrófica da planície costeira do Rio Grande do Sul, Brasil / Floristic composition of the vegetation types of a fen on the southern Brazil coastal plain in Rio Grande do Sul, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Turfeiras topotróficas caracterizam-se como corpos de águas rasas, permanente ou periodicamente alagados por água do lençol freático, percolada através do solo inorgânico das terras altas adjacentes à depressão central da turfeira. Possuem solos orgânicos e a cobertura vegetal é dominanda por faneró [...] gamas aquáticas emergentes. Este estudo visou o levantamento da diversidade específica e caracterização das principais formações vegetais ao longo de duas transecções de 200m em uma turfeira topotrófica na localidade de Domingos Petrolini (Rio Grande, RS). Em março/1998, o total de 48 espécies vegetais (30 famílias) foram encontradas nas 40 parcelas de 5m × 2m observadas nas duas transecções efetuadas. Cerca de 56% das espécies eram plantas aquáticas herbáceas (submersas, flutuantes ou emergentes) e apenas 10% arbustos ou árvores. Sete espécies dominaram a cobertura vegetal (Eupatorium tremulum, Eryngium pandanifolium, Blechnum brasiliense, Rhynchospora sp., Xyris jupicai, Utricularia gibba e Cladium jamaicense). Quatro formações vegetais tipicamente distribuídas em relação à topografia e à distância do lençol freático foram caracterizadas: (1) banhados do capim-navalha Cladium jamaicense, drenados apenas no verão, ocupam a depressão central da turfeira (DCT); (2) planos médios de Gravatás/Caraguatás (Eryngium pandanifolium) associados a samambaia Blechnum brasiliense (+0,5 a +1,5m da DCT); (3) bosques marginais de arbustos palustres (+1 a +3m da DCT) são dominados por Eupatorium tremulum; e (4) campos de turfa recobertos por ciperáceas de pequeno porte, gramas boiadeiras e botões-de-ouro (Xyris jupicai) ocupam a borda do afloramento da turfa (+3 a +4m da DCT). Abstract in english Fens are characterized as shallow water bodies permanently or periodically flooded by ground-water table, originating from the percolation of rain water through mineral soils of uplands adjacent to the fen central basin. Fens have organic soil and their plant cover is dominat by emergent phanerophyt [...] es. This study aims to survey the specific diversity and characterize the main vegetation types along two 200m transects positioned in a fen of the southern Brazilian county of Domingos Petrolini (32° 02' S; 52° 17' W; Rio Grande, RS). In March/1998, 48 plant species (30 families) were recorded in forty 5m × 2m plots along the two transects. Herbaceous aquatic macrophytes (submersed, flooting or emergent) represented 56% of species, but 10% were shrubs or trees. Seven species dominate the vegetation (Eupatorium tremulum, Eryngium pandanifolium, Blechnum brasiliense, Rhynchospora sp., Xyris jupicai, Utricularia gibba, and Cladium jamaicense). The vegetation types include (1) summer exposed swampsdominated by Cladium jamaicense (placed in the fen central basin; FCB), (2) intermediate level of Gravatás/Caraguatás (Eryngium pandanifolium) associated with the fern Blechnum brasiliense (+0.5 to +1.5m from the FCB), (3) marginal palustrine shrubs (+1 to +3m from the FCB) dominated by Eupatorium tremulum and (4) turf fields covered by small sedges, soft-leaved grasses with the yellow-eyed grass (Xyris jupicai) occupying the upper border of the fen (+3 to +4m from the FCB).

César S. B., Costa; Bruno E., Irgang; Aline R., Peixoto; Juliano C., Marangoni.

2003-06-01

305

Vegetation und Management seltener Pflanzenarten im Küstengrünland einer dänischen Ostseeinsel  

DEFF Research Database (Denmark)

Abstract: Grazed coastal grassland in eastern Denmark - Managing plant communities to preserve rare plant species This study analyzes vegetation of coastal grassland in an embanked nature reserve (c. 2000 ha) south of Copenhagen on the island Amager. The focus is on grazing effects on abundance of Iris spuria, Selinum dubium and Cerastium subtetrandrum. The main objectives are to identify plant communities and site factors related to the target species. Considering the ecological requirements of the species it is possible to estimate their potential distribution in the study area. Based on these results, management on the rare plants is discussed. Vegetation data, consisting of 73 relevés collected in summer 2008, are classified using TWINSPAN analysis and ordination by DCA. Thus, the main vegetation units and underlying environmental gradients are identified and assigned to plant communities known from the literature. Recent vegetation changes are analysed by DCA using published data from 2004 and 2006. The main factors defining the grassland vegetation of Vestamager are salinity, moisture and grazing. Nutrientpoor, salt-affected and grazed communities of the Lolio-Cynosuretum are the most common vegetation type in the study area. This association can be divided into a subtype of moist grassland, including species of wetland meadows (Molinion), and drier grassland, with floristic affinities to Mesobromion. In the southwest of the study area, with slightly higher salinity, the Lolio-Cynosuretum is replaced by 243 Juncetum gerardii salt marshes. Within the salt marshes pioneer vegetation is developed on ant hills. The transition between geo- and hydrolitoral is colonized by brackish reeds. On intensely grazed, moist to wet sites the Lolio-Cynosuretum is replaced by the Ranunculo repentis-Alopecuretum geniculati. Tall grassland dominated by Calamagrostis epigejos develops under reduced grazing pressure. Iris spuria and Selinum dubium occur with one stand each in the north of the study area. Thepopulations are associated with drier parts of the Lolio-Cynosuretum juncetosum gerardii. Smaller populations of Selinum dubium are found in Plantago major communities. Cerastium subtetrandrum is represented with several small populations on ant hills in salt-pioneer marsh. Iris spuria is sensitive to grazing, and thus the intensification of grazing on Vestamager has resulted in a decreasing population of this species in the past years. Selinum dubium is more tolerant, and vegetative individuals are able to persist in grazed areas. Cerastium subtetrandrum depends indirectly on grazing. Potential habitats of this species are maintained by grazing. Intensification of grazing and shrub clearance have reduced cover of woody species and tall grasses promoting less competitive species. Recently, a development towards open saltinfluenced grassland can be observed, albeit without increasing floristic diversity. Optimal conservation of the target species seems only feasible if a more diverse management is applied. For conservation of Iris spuria and Selinum dubium a local reduction of grazing is recommended including exclosures. Preservation of Cerastium subtetrandrum, however, depends on low vegetation, which calls for relatively intense grazing. In the long term, higher diversity will only be achieved by spatio-temporal variation of grazing intensity which would also accommodate the different demands of the target species.   Keywords: Cerastium subtetrandrum, conservation management, grazing variation, Iris spuria, salt marsh, Selinum dubium, target species.

Heimes, Christine; Kollmann, Johannes Christian

2010-01-01

306

Fungos micorrízicos arbusculares em fitofisionomias do Pantanal da Nhecolândia, Mato Grosso do Sul / Arbuscular mycorrhizal fungi in vegetation types in the Pantanal of Nhecolândia, Mato Grosso do Sul, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O bioma Pantanal é reconhecido como uma das maiores extensões úmidas contínua do planeta, com fauna e flora de rara beleza e abundância. Estudos para acessar a diversidade de fungos micorrízicos arbusculares (FMA) nesse ambiente são inexistentes. O objetivo deste trabalho foi avaliar a ocorrência de [...] FMA nas diferentes fitofisionomias do Pantanal da Nhecolândia, Mato Grosso do Sul. Foram coletadas amostras de solo no período seco e chuvoso em um Neossolo Quartzarênico, em fitofisionomias sujeitas a distintos regimes de inundação: livres de inundação - Floresta Semidecídua (FS) e Cerradão (CE); sujeitos à inundação ocasional - Campo limpo, predominando Elyonorus muticus (CLE) e Cerrado (CC); e sujeitos à inundação sazonal - Campo limpo, predominando Andropogon spp. (CLA), borda de baias (BB) e vazante/baixadas (VB). Culturas armadilhas foram estabelecidas com Brachiaria brizantha para recuperar espécies crípticas de FMA. De cada amostra de solo, foram realizadas a caracterização química do solo e extração dos esporos de FMA para determinar abundância, riqueza e identificação das espécies. Um total de 37 espécies de FMA, pertencentes a 10 gêneros e seis famílias foram detectadas nas duas estações de coleta. O número de esporos variou significativamente entre as fitofisionomias, e os maiores valores foram encontrados em CE e CLA. A maior riqueza específica foi detectada em CC (25 espécies) seguida de VB e CE com 22 e 21 espécies, respectivamente. Os resultados deste estudo sugeriram que a diversidade dos FMA está relacionada com a heterogeneidade existente entre as fitofisionomias, e que características químicas do solo têm influência na estruturação das comunidades desses fungos. Considerando que o bioma Pantanal é um dos ecossistemas mais conservado do planeta, o levantamento de ocorrência de FMA realizado neste trabalho forneceu informações importantes para melhor conhecimento da biodiversidade das fitofisionomias do Pantanal da Nhecolândia. Abstract in english The Pantanal (tropical wetland) biome is recognized as one of the largest continuous areas of natural wetlands, harboring a flora and fauna of rare beauty and abundance. Studies to assess the diversity of arbuscular mycorrhizal fungi (AMF) are nonexistent for this environment. The goal of this study [...] was to evaluate the occurrence of AMF in different vegetation types of the Pantanal of Nhecolândia, Brazil. Soil samples were collected during the dry and wet season in a Neossolo Quartzarênico (Entisol) in vegetation types subject to different flooding regimes: flood-free - semi-deciduous forest (FS) and "Cerradão" (CE); subject to occasional flooding - grassland dominated by Elyonurus muticus (CLE) and "Cerrado" (CC); and subject to seasonal flooding - grasslands dominated by Andropogon spp. (CLA), the edge of bays (BB), and areas exposed at low water/lowlands (VB). Trap crops were established with Brachiaria brizantha to recover cryptic AMF species. Chemical analyses and spore extraction were carried for each soil sample to identify AMF species and determine their abundance and richness. A total of 37 AMF species, belonging to 10 genera and six families, were detected for both seasons. Spore numbers varied significantly among vegetation types, and the highest values were found in CE and CLA. The greatest richness of species was detected in CC (25 species), followed by VB, with 22 species, and CE, with 21 species. This is the first report on AMF diversity from the Pantanal biome. Results of this study suggest that AMF diversity is related to the heterogeneity among vegetation types and that soil chemical characteristics influence the structure of these fungi communities. Considering that the Pantanal is one of the most conserved biomes in the world, the survey of the occurrence of AMF in this study provides important information for better understanding the biodiversity of the phytophysiognomies of this biome.

Plínio Henrique Oliveira, Gomide; Marx Leandro Naves, Silva; Cláudio Roberto Fonsêca Sousa, Soares; Evaldo Luis, Cardoso; Fernanda de, Carvalho; Patrícia Lopes, Leal; Rodrigo Magalhães, Marques; Sidney Luiz, Stürmer.

1114-11-01

307

Field-testing ecological and economic benefits of coffee certification programs.  

Science.gov (United States)

Coffee agroecosystems are critical to the success of conservation efforts in Latin America because of their ecological and economic importance. Coffee certification programs may offer one way to protect biodiversity and maintain farmer livelihoods. Established coffee certification programs fall into three distinct, but not mutually exclusive categories: organic, fair trade, and shade. The results of previous studies demonstrate that shade certification can benefit biodiversity, but it remains unclear whether a farmer's participation in any certification program can provide both ecological and economic benefits. To assess the value of coffee certification for conservation efforts in the region, we examined economic and ecological aspects of coffee production for eight coffee cooperatives in Chiapas, Mexico, that were certified organic, certified organic and fair trade, or uncertified. We compared vegetation and ant and bird diversity in coffee farms and forests, and interviewed farmers to determine coffee yield, gross revenue from coffee production, and area in coffee production. Although there are no shade-certified farms in the study region, we used vegetation data to determine whether cooperatives would qualify for shade certification. We found no differences in vegetation characteristics, ant or bird species richness, or fraction of forest fauna in farms based on certification. Farmers with organic and organic and fair-trade certification had more land under cultivation and in some cases higher revenue than uncertified farmers. Coffee production area did not vary among farm types. No cooperative passed shade-coffee certification standards because the plantations lacked vertical stratification, yet vegetation variables for shade certification significantly correlated with ant and bird diversity. Although farmers in the Chiapas highlands with organic and/or fair-trade certification may reap some economic benefits from their certification status, their farms may not protect as much biodiversity as shade-certified farms. Working toward triple certification (organic, fair trade, and shade) at the farm level may enhance biodiversity protection, increase benefits to farmers, and lead to more successful conservation strategies in coffee-growing regions. PMID:17650248

Philpott, Stacy M; Bichier, Peter; Rice, Robert; Greenberg, Russell

2007-08-01

308

Contributions to multiple element speciation in vegetable plants: Studies on the type of bonding of numerous elements, particularly zinc and cadmium  

International Nuclear Information System (INIS)

In the first part of the study, the total contents and the solubility characteristics of Zn, Cd, Fe, Mn, Cu, Ca, Sr, K and Rb in 26 different vegetable plants, the majority of them commercially available, are reported, obtained by post-decomposition analyses. The data are given for avocados, bananas, cauliflower, chicory, Chinese cabbage, dill, ice lettuce (two specimens), endive, field salad, cucumbers, kohlrabi, lettuce, chard beet, carrots, peppers, leek, radish, red cabbage, loose leaved lettuce, celery (two specimens), spinach, topinambur, white cabbage, and parsley. Cell decomposition was done by treatment of the plant material with an electric dispersing apparatus (Ultra-Turrax) in buffer solution (liquid shearing). The homogenates were separated into supernatants (cytosoles)and pellets by means of centrifugation. Cell decomposition of the plants by crushing with quartz sand after lyophilization (solid shearing) required much more technical effort and for some elements created problems with the blind values. At least 50% on the average of the elements Zn, Cd, Rb, and K could be transferred to the solutions by the dispersing treatment with Ultra-Turrax. In many cases, the cytosole-borne detectable contents of these 5 elements were above 70%. The solubility of Zn and Cd was more strongly dependent on the plant species than that of Cu, Rb, and K. All five elements thus can be analysed by conventional methods for further enhanced speciation. Mn, Ca, and especially hanced speciation. Mn, Ca, and especially Fe and Sr for the most part were found to be bonded to solid cell constituents. However, the solubility characteristics of Ca and Mn and Sr in particular was very homogeneous. In some plants, the contents of Mn and Sr in the cytosoles was approx. 90%, so that comprehensive speciation of these elements is possible. (orig./AJ)

309

Relationships among vegetation, geomorphology and hydrology in the Bananal Island tropical wetlands, Araguaia River basin, Central Brazil  

Science.gov (United States)

The Bananal Plain spreading on the Middle Araguaia River basin in Central Brazil at the Cerrado-Amazonia ecotone is a unique system that sustains the largest seasonal wetlands of the Cerrado biome. The huge Bananal Plain is an intracratonic sedimentary basin filled with Pleistocene sediments of the Araguaia formation. Covering approximately two million hectares, the Bananal Island is a major geomorphologic feature of the Bananal plain. Fieldwork and the analysis of a temporal series of MODIS-VI and Landsat ETM images allowed us to discriminate Cerrado phyto-physiognomies on the Bananal Island. Maps of vegetation and geomorphologic units were created, and from the correlation between landforms and vegetation types we identified morpho-vegetation units. Our approach allowed us to postulate that Pleistocene landforms strongly influence, if not dominate, the distribution of vegetation units. For example, the distribution of current gallery forest is not only controlled by active floodplains, but also by alluvial belts abandoned by avulsion. Additionally, arboreal Cerrado vegetation is supported by laterite developed on the sediments of the Araguaia Formation. Some of these inactive landforms are in part modified by the present day geomorphologic processes and colonized by successional vegetation that varies from alluvial forest to Cerrado. Characterized by a very flat landscape with a hindered drainage, the muddy sediments of the Araguaia Formation and the high seasonal rainfall favor the development of regional seasonal wetlands. The Bananal plain is a key area for understanding the Quaternary climatic and biogeographic changes in tropical South America. The control exerted by relict Quaternary landforms on the current vegetation units demonstrates the strong links between geomorphologic aspects of the landscape and ecological patterns. This multidisciplinary approach provides a better understanding of the biogeographic patterns in the Cerrado-Amazon ecotone, which is useful for identifying and designing areas for conservation.

Valente, C. R.; Latrubesse, E. M.; Ferreira, L. G.

2013-10-01

310

[Treatment effect of biological filtration and vegetable floating-bed combined system on greenhouse turtle breeding wastewater].  

Science.gov (United States)

Unorganized discharge of greenhouse turtle breeding wastewater has brought several negative influences on the ecological environment in the rural area of Yangtze River Delta. Biological filtration and vegetable floating-bed combined system is a potential ecological method for greenhouse turtle breeding wastewater treatment. In order to explore the feasibility of this system and evaluate the contribution of vegetable uptake of nitrogen (N) and phosphorus (P) in treating greenhouse turtle breeding wastewater, three types of vegetables, including Ipomoea aquatica, lettuce and celery were selected in this study. Results showed the combined system had a high capacity in simultaneous removal of organic matter, N and P. The removal efficiencies of COD, NH4(+)-N, TN and TP from the wastewater reached up to 93.2%-95.6%, 97.2%-99.6%, 73.9%-93.1% and 74.9%-90.0%, respectively. System with I. aquatica had the highest efficiencies in N and P removal, followed by lettuce and celery. However, plant uptake was not the primary pathway for TN arid TP removal in the combined system. The vegetable uptake of N and P accounted for only 9.1%-25.0% of TN and TP removal from the wastewater while the effect of microorganisms would be dominant for N and P removal. In addition, the highest amounts of N and P uptake in I. aquatica were closely related with the biomass of plant. Results from the study indicated that the biological filtration and vegetable floating-bed combined system was an effective approach to treating greenhouse turtle breeding wastewater in China. PMID:25509094

Chen, Chong-Jun; Zhang, Rui; Xiang, Kun; Wu, Wei-Xiang

2014-08-01

311

Comparative analysis of remotely-sensed data products via ecological niche modeling of avian influenza case occurrences in Middle Eastern poultry  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Ecological niche modeling integrates known sites of occurrence of species or phenomena with data on environmental variation across landscapes to infer environmental spaces potentially inhabited (i.e., the ecological niche to generate predictive maps of potential distributions in geographic space. Key inputs to this process include raster data layers characterizing spatial variation in environmental parameters, such as vegetation indices from remotely sensed satellite imagery. The extent to which ecological niche models reflect real-world distributions depends on a number of factors, but an obvious concern is the quality and content of the environmental data layers. Methods We assessed ecological niche model predictions of H5N1 avian flu presence quantitatively within and among four geographic regions, based on models incorporating two means of summarizing three vegetation indices derived from the MODIS satellite. We evaluated our models for predictive ability using partial ROC analysis and GLM ANOVA to compare performance among indices and regions. Results We found correlations between vegetation indices to be high, such that they contain information that overlaps broadly. Neither the type of vegetation index used nor method of summary affected model performance significantly. However, the degree to which model predictions had to be transferred (i.e., projected onto landscapes and conditions not represented on the landscape of training impacted predictive strength greatly (within-region model predictions far out-performed models projected among regions. Conclusion Our results provide the first quantitative tests of most appropriate uses of different remotely sensed data sets in ecological niche modeling applications. While our testing did not result in a decisive "best" index product or means of summarizing indices, it emphasizes the need for careful evaluation of products used in modeling (e.g. matching temporal dimensions and spatial resolution for optimum performance, instead of simple reliance on large numbers of data layers.

Xiao Xiangming

2011-03-01

312

Challenges in writing ecological site descriptions  

Science.gov (United States)

The Natural Resources Conservation Service (NRCS) adopted the Ecological Site Description (ESD) concept in 1997. The State and Transition Model (STM) is used to describe vegetation dynamics and is an integral component of ESDs that meet users needs. NRCS is currently developing ESDs for much of the ...

313

Aspectos florísticos e ecológicos da vegetação campestre do Morro da Polícia, Porto Alegre, RS, Brasil / Floristics and ecological aspects of a grassland vegetation on Morro da Polícia, Porto Alegre, RS, Brazil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Estudou-se a variação da composição florística da vegetação campestre e suas relações com altitude e exposição no Morro da Polícia, de origem granítica, em Porto Alegre, Rio Grande do Sul, a 30ºS e 51 ºW. O levantamento foi realizado de novembro de 1992 a novembro de 1994. A presença e freqüência de [...] espécies foi avaliada usando o método de pontos sobre transecções em 19 unidades de vegetação, as quais foram delimitadas com base na exposição da encosta (N, S, L, O) e altitude (160 a 280m). Os dados foram submetidos a análise multivariada de agrupamentos e ordenação. Nas transecções foram observadas 189 espécies, sendo Poaceae, Asteraceae e Apiaceae as famílias mais freqüentes e Trachypogon montufari e Schizachyrium tenerum as espécies dominantes. A análise de agrupamentos e de ordenação revelou conexões entre variação da vegetação e fatores altitude e exposição solar. Aristida laevis e Sorghastrum albescens são características de comunidades mais expostas à radiação solar, enquanto Agenium villosum e Eryngium eriophorum o são de comunidades menos expostas. Vernonia nudiflora e Axonopus suffultus caracterizam as áreas mais elevadas do morro, enquanto Eupatoriitm ligulifolium e Sorghastrum albescens as mais baixas. Abstract in english We studied floristic composition variation and its conections to elevation and exposure in the grassland vegetation of Morro da Polícia, a hill of granitic origin in the city of Porto Alegre, Rio Grande do Sul, 30ºS e 51 ºW. The survey took place from November 1992 to November 1994. Species presence [...] and frequency were assessed by using the point method on transects in 19 vegetation units, which were delimited by slope exposure and elevation (160 to 280m). Data were subjected to cluster analysis and ordination. Based on data from transects we detected 189 species, mainly from the Poaceae, Asteraceae and Apiaceae families, with Trachypogon montufari and Schizachyrium tenerum as dominant species. Cluster analysis and ordination revealed conections of vegetation variation with elevation and exposure. Aristida laevis and Sorghastrum albescens are characteristic of more exposed comunities (N and NE slopes), while Agenium villosum and Eryngium eriophorum are from less exposed communities (on S and SW slopes). Vernonia nudiflora and Axonopus suffultus are characteristic of higher elevation areas on the hill, while Eupatorium ligulifolium and Sorghastrum albescens are characteristic of lower elevation areas.

Ilsi Iob, Boldrini; Silvia T. S, Miotto; Hilda M, Longhi-Wagner; Valério De P, Pillar; Katia, Marzall.

1998-04-01

314

MODIS Vegetative Cover Conversion and Vegetation Continuous Fields  

Science.gov (United States)

Land cover change occurs at various spatial and temporal scales. For example, large-scale mechanical removal of forests for agro-industrial activities contrasts with the small-scale clearing of subsistence farmers. Such dynamics vary in spatial extent and rate of land conversion. Such changes are attributable to both natural and anthropogenic factors. For example, lightning- or human-ignited fires burn millions of acres of land surface each year. Further, land cover conversion requires ­contrasting with the land cover modification. In the first instance, the dynamic represents extensive categorical change between two land cover types. Land cover modification mechanisms such as selective logging and woody encroachment depict changes within a given land cover type rather than a conversion from one land cover type to another. This chapter describes the production of two standard MODIS land products used to document changes in global land cover. The Vegetative Cover Conversion (VCC) product is designed primarily to serve as a global alarm for areas where land cover change occurs rapidly (Zhan et al. 2000). The Vegetation Continuous Fields (VCF) product is designed to continuously ­represent ground cover as a proportion of basic vegetation traits. Terra's launch in December 1999 afforded a new opportunity to observe the entire Earth every 1.2 days at 250-m spatial resolution. The MODIS instrument's appropriate spatial and ­temporal resolutions provide the opportunity to substantially improve the characterization of the land surface and changes occurring thereupon (Townshend et al. 1991).

Carroll, Mark; Townshend, John; Hansen, Matthew; DiMiceli, Charlene; Sohlberg, Robert; Wurster, Karl

315

Site study plan for ecology, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary Draft  

International Nuclear Information System (INIS)

The Ecology Site Study Plan describes a field program consisting of studies which include surveys for endangered, threatened, and candidate species; vegetation characterization, including mapping and cover typing, plant succession, wetlands description, and preexisting stresses; and wildlife community characterization, including availability and quality of habitats and descriptions of mammal, bird, reptile, amphibian, and invertebrate populations. The plan for each study describes the need for the study, study design, data management and use, schedule and personnel requirements, and quality assurance. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project Requirements Document (SRP-RD). 83 refs., 3 tabs

316

Fire does not alter vegetation in infertile prairie.  

Science.gov (United States)

The paradigm in prairie ecology is that fire is one of the key factors determining vegetation composition. Fire can impact grassland ecosystems in various ways, including changing plant species composition and inducing nitrogen loss. I found that 17 years of different burning frequencies in infertile grassland had only a minor impact on the vegetation composition and diversity. The only major impact from increasing the frequency of fires was a decrease of Poa pratensis abundance. However, other plant species did not respond to the change in Poa abundance. This result contrasts with previous studies in savannas and more productive grasslands, where the balance between trees, grasses, and the elimination of the litter layer can result in large vegetation changes. However, in this system primary productivity was low, litter did not accumulate and no major vegetation shifts occurred. Thus, the long-term vegetation impacts of burning in an infertile, low-productivity prairie were minimal. PMID:16941181

Knops, Johannes M H

2006-12-01

317

Effect of harvest at different times of day on the physical and chemical characteristics of vegetable-type soybean / Efeito da colheita em diferentes horários do dia sobre as características químicas e físicas de soja tipo hortaliça  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese O trabalho teve como objetivo avaliar o efeito da colheita em diferentes horários do dia sobre as características químicas e físicas dos grãos de soja da cultivar tipo hortaliça BRS 267, colhidos no estádio R6 (desenvolvimento da semente), e comparar com os colhidos no estádio R8 (maturação). As vag [...] ens da cultivar BRS 267 foram colhidas no estádio de desenvolvimento R6 nos horários das 8, 12 e 18 horas e avaliadas a cor e os grãos analisados quanto à composição química, atividade do inibidor de tripsina, teor do ácido fítico, amido, açúcares, ácidos graxos e isoflavonas. O teor de isoflavonas não diferiu entre os diferentes horários de colheita no estádio R6. No estádio R8 foi encontrado maior teor das formas agliconas. Os diferentes horários de colheita não influenciaram na cor das vagens e nos constituintes químicos dos grãos da cultivar BRS 267 colhida no estádio R6. Os grãos colhidos no estádio R6, quando comparados com os colhidos no estádio R8, apresentaram menor teor de proteínas, ácido fítico e sacarose e maior teor de lipídios, carboidratos, amido, glicose, frutose, estaquiose e ácido linolênico. A qualidade da soja tipo hortaliça BRS 267 no estádio R6 não diferiu com os diferentes horários de colheita, contudo, como produto tipo hortaliça, recomenda-se que a colheita seja realizada no período da manhã, cuja temperatura é mais amena, para facilitar a rápida comercialização e consumo como alimento in natura. Abstract in english The objective of this study was to evaluate the effect of harvest at different times of day on the chemical and physical characteristics of vegetable-type soybean BRS 267 cultivar, harvested at the R6 stage (seed development) and to compare it with that on the grains harvested at the R8 stage (matur [...] ation). The pods of the BRS 267 cultivar were harvested at the R6 stage (at 8:00 AM, 12:00 AM, and 6:00 PM), the color parameters were evaluated, and the grains were analyzed for chemical composition, activity inhibitor trypsin, phytic acid content, starch, sugars, fatty acids, and isoflavones. No differences were observed among the different harvest times in terms of the chemical constituents of vegetable-type soybean BRS 267 cultivar harvested at the R6 stage. Isoflavones content did not change with different harvest times, and the aglycone forms (daidzein, glycitein, and genistein) were found in smaller quantities at the R6 stage compared to the R8 stage. The color of the pods of soybean BRS 267 cultivar, harvested at the R6 stage did not change with different harvest times. The grains harvested at the R6 stage had lower protein content, phytic acid, and sucrose and higher levels of lipids, carbohydrates, starch, glucose, fructose, stachyose, and linolenic acids than those collected at the R8 stage. The different times of harvest did not affect the quality of the vegetable-type soybean BRS 267 cultivar harvested at stage R6. Nevertheless, it is recommended to harvest in the morning, when the temperature is milder, like other vegetables, to facilitate and optimize its marketing and in natura consumption.

Andréia Cristina, Santana; Mercedes Concórdia, Carrão-Panizzi; José Marcos Gontijo, Mandarino; Rodrigo Santos, Leite; Josemeyre Bonifácio da, Silva; Elza Iouko, Ida.

2012-06-01

318

Effect of harvest at different times of day on the physical and chemical characteristics of vegetable-type soybean Efeito da colheita em diferentes horários do dia sobre as características químicas e físicas de soja tipo hortaliça  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this study was to evaluate the effect of harvest at different times of day on the chemical and physical characteristics of vegetable-type soybean BRS 267 cultivar, harvested at the R6 stage (seed development and to compare it with that on the grains harvested at the R8 stage (maturation. The pods of the BRS 267 cultivar were harvested at the R6 stage (at 8:00 AM, 12:00 AM, and 6:00 PM, the color parameters were evaluated, and the grains were analyzed for chemical composition, activity inhibitor trypsin, phytic acid content, starch, sugars, fatty acids, and isoflavones. No differences were observed among the different harvest times in terms of the chemical constituents of vegetable-type soybean BRS 267 cultivar harvested at the R6 stage. Isoflavones content did not change with different harvest times, and the aglycone forms (daidzein, glycitein, and genistein were found in smaller quantities at the R6 stage compared to the R8 stage. The color of the pods of soybean BRS 267 cultivar, harvested at the R6 stage did not change with different harvest times. The grains harvested at the R6 stage had lower protein content, phytic acid, and sucrose and higher levels of lipids, carbohydrates, starch, glucose, fructose, stachyose, and linolenic acids than those collected at the R8 stage. The different times of harvest did not affect the quality of the vegetable-type soybean BRS 267 cultivar harvested at stage R6. Nevertheless, it is recommended to harvest in the morning, when the temperature is milder, like other vegetables, to facilitate and optimize its marketing and in natura consumption.O trabalho teve como objetivo avaliar o efeito da colheita em diferentes horários do dia sobre as características químicas e físicas dos grãos de soja da cultivar tipo hortaliça BRS 267, colhidos no estádio R6 (desenvolvimento da semente, e comparar com os colhidos no estádio R8 (maturação. As vagens da cultivar BRS 267 foram colhidas no estádio de desenvolvimento R6 nos horários das 8, 12 e 18 horas e avaliadas a cor e os grãos analisados quanto à composição química, atividade do inibidor de tripsina, teor do ácido fítico, amido, açúcares, ácidos graxos e isoflavonas. O teor de isoflavonas não diferiu entre os diferentes horários de colheita no estádio R6. No estádio R8 foi encontrado maior teor das formas agliconas. Os diferentes horários de colheita não influenciaram na cor das vagens e nos constituintes químicos dos grãos da cultivar BRS 267 colhida no estádio R6. Os grãos colhidos no estádio R6, quando comparados com os colhidos no estádio R8, apresentaram menor teor de proteínas, ácido fítico e sacarose e maior teor de lipídios, carboidratos, amido, glicose, frutose, estaquiose e ácido linolênico. A qualidade da soja tipo hortaliça BRS 267 no estádio R6 não diferiu com os diferentes horários de colheita, contudo, como produto tipo hortaliça, recomenda-se que a colheita seja realizada no período da manhã, cuja temperatura é mais amena, para facilitar a rápida comercialização e consumo como alimento in natura.

Andréia Cristina Santana

2012-06-01

319

Phytoplankton Ecology  

Science.gov (United States)

This site describes phytoplankton ecology research by marine ecologists at Mote Marine Laboratory (MML), an independent, nonprofit research organization based in Sarasota, Florida. The emphasis of MML's phytoplankton ecology research is the photophysiology of marine algae -- with recent emphasis on the ability to predict and possibly mitigate blooms of the toxic marine dinoflagellate, Gymnodinium breve. The no-frills phytoplankton ecology homepage describes research and offers data (maps, figures, tables) from 1998 and 1999 projects on Red Tide transects, Nutrient and chlorophyll concentrations, and Ecology and Oceanography of Harmful Algal Blooms (ECOHAB) transect data, among several others. The site also offers general information on Red Tides, Red Tide conditions in Southwest Florida, a chronology of historic Red Tide events, and links to related resources.

320

Ecological shortage  

International Nuclear Information System (INIS)

The Meadows study (Limits to Growth) has made the environmental problem popular, but it has reduced the ecological problem to one of population and raw materials, leaving the conditions of social organisation and developmental policy out of consideration. This means that in spite of the repeated moral appeals, developing countries are left to their natural fate while fear and resignation are spread in the industrial nations. The present study tries to contradict this trend in consideration of interdependences in ecological development. (orig.)

 
 
 
 
321

[Effects of different fertilization regimes on abundance and community structure of the nirK-type denitrifying bacteria in greenhouse vegetable soils].  

Science.gov (United States)

The community structure and abundance of nirK-type denitrifying bacteria in different soil layers (0-20 cm and 20-40 cm) under various fertilization regimes in Wuwei, Gansu Province were investigated by the combination of terminal restriction fragment length polymorphism (T-RFLP) and real-time quantitative PCR. Results showed that the nirK-type denitrifying bacteria community structure was significantly affected by fertilization regimes, especially for 70, 156 and 190 bp T-RFs that represented the dominant populations in greenhouse soil. Fertilization regimes significantly influenced the abundance of nirK gene in the 0-20 cm soil layer with the highest abundance of nirK gene copy number (2.16 x 10(7) copies x g(-1) soil) detected in the manure treatment (M), which was 2.04 and 2.02 times of that in the control (CK) and chemical fertilizer (NPK) treatments, respectively. Both the dominant population and abundance of nirK-type denitrifying bacteria in the greenhouse soil were significantly different between the 0-20 cm and 20-40 cm soil layers, and the nirK-type denitrifying bacteria community structure and abundance in the greenhouse soil were obviously different from that in the field. Soil pH, soil organic matter content and nitrate-N content had the greatest influence on the bacterial community composition. Phylogenetic analysis indicated that there were not only anaerobic nirK-type denitrifying bacteria in greenhouse soil, but also aerobic denitrifying bacteria, such as Rhizobium, Ochrobactrum, Agrobacterium. PMID:24830252

Zeng, Xi-Bai; Wang, Ya-Nan; Wang, Yu-Zhong; Bai, Ling-Yu; Li, Lian-Fang; Duan, Ran; Su, Shi-Ming; Wu, Cui-Xia

2014-02-01

322

Research on Chengdu Vegetables Marketing Based on STP Model  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, we take the consumers in Chengdu vegetables market as samples, in the form of questionnaires and interviews, to study the consumer motivations and psychology, and make market segmentation of consumers. Results show that the consumers in Chengdu vegetables market can be divided into four types: the safety-pursuing type, the convenient and economical type, the family healthy type, and the fashionable type, among which the safety-pursuing type is the largest. Finally, authors put forward some suggestions for Chengdu vegetables market based on current conditions.

Qiang Liu

2013-04-01

323

Founding RGB ecology: The ecology of synthesis  

Directory of Open Access Journals (Sweden)

Full Text Available There is an arising need to interpret an amount of ecological information that is more and more available. It is not only the pursuit of an easy handling of a large amount of data, but above all the quest for a deep and multivariate interpretation of many sources of ecological info. To this aim, I introduce here RGB ecology as a new branch of ecology devoted to the cartographic synthesis of ecological information. RGB ecology has the following properties: (1 it can not be separated from GIS cartography; (2 it can compact ecological information along space and time; (3 it can create a decision space for management decisions; (4 it can go beyond the third dimension by using compressive statistical techniques. RGB ecology can also be an effective flanker of several branches of ecology, such as landscape ecology, conservation ecology, urban ecology, forest ecology and so forth.

Alessandro Ferrarini

2012-06-01

324

Predicciones de cambios en los principales tipos de vegetación de Chile bajo cambio climático basados en un estudio preliminar: Modelos, incertidumbres y adaptación de la investigación para un mundo de biodiversidad dinámica Changes in the main vegetation types of Chile predicted under climate change based on a preliminary study: Models, uncertainties and adapting research to a dynamic biodiversity world  

Directory of Open Access Journals (Sweden)

Full Text Available Los efectos del cambio climático sobre la biodiversidad ocurren a diferentes niveles de organización (organismos, especies y ecosistemas. La vegetación se encuentra relacionada directamente con el clima, por lo que se espera que el calentamiento global altere la distribución de los tipos de vegetación para el futuro cercano. Usando un enfoque de envoltura bioclimática, los tipos de vegetación de Chile fueron modelados y proyectados usando escenarios del IPCC para el año 2080. Los resultados presentan diferentes transiciones entre los tipos de vegetación, en relación a su distribución latitudinal y altitudinal actual. Entre los cambios principales, se identifica el avance altitudinal de la vegetación alpina, la expansión hacia el sur del desierto absoluto y del matorral desértico sobre el bosque escleróflo. Se esperan cambios en la representación relativa de las áreas protegidas dentro de los diferentes tipos de vegetación de Chile. Las limitaciones del ejercicio de modelación son discutidas junto a la necesidad de mejorar el conocimiento científico sobre procesos biológicos claves como dispersión y polinización.Climate change effects on biodiversity occur at different level of organization (organisms, species and ecosystems. Vegetation type bears a close relationship with climate, such that global warming is ex-pected to alter the distribution of major vegetation types in the near future. Using a bioclimatic envelope modeling approach, the major vegetation types of Chile were modeled and projected using IPCC scenarios for year 2080. The results show transitions among vegetation types in relation to their current latitudinal and altitudinal distribution. Major changes include an upward shift of the alpine vegetation and southward expansion of absolute desert and desert scrub into the present area of sclerophyllous forest. Changes in the relative representation of different vegetation types in Chile´s protected areas can be expected. The limitations of modeling exercises are discussed along with need for better scientific knowledge on key biological processes such as dispersal and pollination.

Patricio Pliscoff

2012-01-01

325

Predicciones de cambios en los principales tipos de vegetación de Chile bajo cambio climático basados en un estudio preliminar: Modelos, incertidumbres y adaptación de la investigación para un mundo de biodiversidad dinámica / Changes in the main vegetation types of Chile predicted under climate change based on a preliminary study: Models, uncertainties and adapting research to a dynamic biodiversity world  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish Los efectos del cambio climático sobre la biodiversidad ocurren a diferentes niveles de organización (organismos, especies y ecosistemas). La vegetación se encuentra relacionada directamente con el clima, por lo que se espera que el calentamiento global altere la distribución de los tipos de vegetac [...] ión para el futuro cercano. Usando un enfoque de envoltura bioclimática, los tipos de vegetación de Chile fueron modelados y proyectados usando escenarios del IPCC para el año 2080. Los resultados presentan diferentes transiciones entre los tipos de vegetación, en relación a su distribución latitudinal y altitudinal actual. Entre los cambios principales, se identifica el avance altitudinal de la vegetación alpina, la expansión hacia el sur del desierto absoluto y del matorral desértico sobre el bosque escleróflo. Se esperan cambios en la representación relativa de las áreas protegidas dentro de los diferentes tipos de vegetación de Chile. Las limitaciones del ejercicio de modelación son discutidas junto a la necesidad de mejorar el conocimiento científico sobre procesos biológicos claves como dispersión y polinización. Abstract in english Climate change effects on biodiversity occur at different level of organization (organisms, species and ecosystems). Vegetation type bears a close relationship with climate, such that global warming is ex-pected to alter the distribution of major vegetation types in the near future. Using a bioclima [...] tic envelope modeling approach, the major vegetation types of Chile were modeled and projected using IPCC scenarios for year 2080. The results show transitions among vegetation types in relation to their current latitudinal and altitudinal distribution. Major changes include an upward shift of the alpine vegetation and southward expansion of absolute desert and desert scrub into the present area of sclerophyllous forest. Changes in the relative representation of different vegetation types in Chile´s protected areas can be expected. The limitations of modeling exercises are discussed along with need for better scientific knowledge on key biological processes such as dispersal and pollination.

Patricio, Pliscoff; Mary T. K, Arroyo; Lohengrin, Cavieres.

326

Survey of ecological resources at selected US Department of Energy sites  

International Nuclear Information System (INIS)

The U.S. Department of Energy (DOE) owns and manages a wide range of ecological resources. During the next 30 years, DOE Headquarters and Field Offices will make land-use planning decisions and conduct environmental remediation and restoration activities in response to federal and state statutes. This document fulfills, in part, DOE's need to know what types of ecological resources it currently owns and manages by synthesizing information on the types and locations of ecological resources at 10 DOE sites: Hanford Site, Idaho National Engineering Laboratory, Lawrence Livermore National Laboratory, Sandia National Laboratory, Rocky Flats Plant, Los Alamos National Laboratory, savannah River Site, Oak Ridge National Laboratory, Argonne National Laboratory, and Fernald Environmental Management Project. This report summarizes information on ecosystems, habitats, and federally listed threatened, endangered, and candidate species that could be stressed by contaminants or physical activity during the restoration process, or by the natural or anthropogenic transport of contaminants from presently contaminated areas into presently uncontaminated areas. This report also provides summary information on the ecosystems, habitats, and threatened and endangered species that exist on each of the 10 sites. Each site chapter contains a general description of the site, including information on size, location, history, geology, hydrology, and climate. Descriptions of the major vegetation and animal communities and of aquatic resources are also provided, with discussions of the treatened or endangered plant or animal species present. Site-specific ecological issues are also discussed in each site chapter. 106 refs., 11 figs., 1 tab

327

Analysis of the vegetation of the sandstone ridges (Ib land type) of the north-eastern parts of the Mapungubwe National Park, Limpopo Province, South Africa  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english The establishment of the Mapungubwe National Park has been an objective of several conservationists for many years. The ultimate objective is that this park should become a major component of a Transfrontier National Park shared by Botswana, Zimbabwe and South Africa. The aim of this study was to id [...] entify, classify and describe the plant communities present in the Ib land type of the park. Sampling was done by means of the Braun-Blanquet method. A total of 48 stratified random relevés were sampled in the Ib land type. All relevé data were imported into a TURBOVEG database, after which the numerical classification technique TWINSPAN was used as a first approximation. Subsequently, Braun-Blanquet procedures were used to refine data and a phytosociological table was constructed, using the visual editor, MEGATAB. Two plant communities and several subcommunities and variants were identified and described from the phytosociological table.

Albie R., Götze; Sarel S., Cilliers; Hugo, Bezuidenhout; Klaus, Kellner.

328

Analysis of the vegetation of the sandstone ridges (Ib land type of the north-eastern parts of the Mapungubwe National Park, Limpopo Province, South Africa  

Directory of Open Access Journals (Sweden)

Full Text Available The establishment of the Mapungubwe National Park has been an objective of several conservationists for many years. The ultimate objective is that this park should become a major component of a Transfrontier National Park shared by Botswana, Zimbabwe and South Africa. The aim of this study was to identify, classify and describe the plant communities present in the Ib land type of the park. Sampling was done by means of the Braun-Blanquet method. A total of 48 stratified random relevés were sampled in the Ib land type. All relevé data were imported into a TURBOVEG database, after which the numerical classification technique TWINSPAN was used as a first approximation. Subsequently, Braun-Blanquet procedures were used to refine data and a phytosociological table was constructed, using the visual editor, MEGATAB. Two plant communities and several subcommunities and variants were identified and described from the phytosociological table.

Hugo Beduizenhout

2008-05-01

329

Effect oof some antibiotics, disinfectants, and UV light on vability of vegetative cells and spores of C1. perfringend type A  

International Nuclear Information System (INIS)

Cells and spores of 40 strains of C1. perfringens type A, pathogenic for guinea pigs, were tested for resistance to antibiotics, drugs, disinfectants used in surgery and in bacteriological laboratories, and UV light. No correlation was found between thermoresistance of spores and their resistance to other bactericidal agents. Among the common disinfectants, iodine solution showed strong bactericidal and sporostatic activity. Good bactericidal effect was also obtained by combined action of Vescodin and UV light. Drug resistance of C1. perfringens type A strains changed clearly in the past 10 years. Strains inducing gangrene became resistant to penicillin and tetracyclines, which hitherto were commonly applied. Ampicilin can now be recommended, as the antibiotic with strong bactericidal and sporostatic action. (author)

330

Fire Ecology  

Science.gov (United States)

Forest fires have become a regular summertime occurrence in North America, sparking debate about the proper role of fire on the land. The following websites examine fires and fire ecology in different ecosystems, regions, and time periods. The first site (1), from the USGS-Western Ecological Research Center shares information about fire ecology research in the California shrublands, Sierra Nevada forests, and Mohave and Sonoran deserts. The second site (2) features the Fire Ecology Center at Texas Tech University. The Fire Ecology Center focuses on the role of fire in grassland ecosystems and their website contains information on current research, publications, managing pastures, managing problem plants, and more. The third site (3), from the USGS-Northern Prairie Wildlife Research Center contains "an annotated bibliography on fire in North American wetland ecosystems and a subject index of all fire-related literature that has appeared in Wildlife Review." Hosted by Yellowstone National Park, the fourth site (4) addresses wildland fires in Yellowstone. The Park website presents brief sections on Fire Ecology, Fire Monitoring, Prescribed Fire, and Fire Effects -- to name a few. The fifth (5) site, from the Canadian Forest Service, provides information about forest fires in Canada including weekly fire statistics, fire research, daily fire maps, a fire database, and more. Part of a great site on the land use history of the Colorado Plateau from Northern Arizona University, the sixth site (6) offers a brief overview of wildfire history and ecology on the Plateau with links to information about ponderosa pine fire ecology, reintroduction of fire to forest ecosystems, and fire ecology research studies. The seventh site (7), from DiscoverySchool.com, contains a lesson plan on forest fire ecology for grade levels 9-12. The lesson spans two class periods and the site provides objectives, materials needed, discussion questions, academic standards, and more. The final (8) website, from the Why Files, "examines the role of fire in natural systems, and the role of science in understanding wildfires." The eleven-page website follows a kid-friendly narrative format and includes a bibliography and glossary.

331

Development of multi-criteria model for the assessment of vegetable production in protected space  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This research is primarily based on the development of a techno-economical simulation model for integrated production of vegetables, its reorientation and ecological production of commercially attractive vegetables (growing pepper, lettuce, salad cucumber) in a protected space. Developed simulation models were then used for evaluation of the most important economical parameters for individual vegetables with various production methods. Simulation results provided an information basis of suffi...

Pozderec, Silvo

2012-01-01

332

The underutilized vegetable plants of the federal capital territory (FCT) Abuja of Nigeria  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Promotion and conservation of underutilized indigenous vegetable plants for healthy diet, income generation and food security are the main aims of this ecological survey. Sixty species of flowering plants underutilized as vegetables were collected from the field in the Federal Capital Territory (FCT), across all the six area councils). The family Fabaceae has the highest number of species followed by Asteraceae. Thirty four (56.7%), of the vegetables are herbs, twenty (33.3%) are trees, while...

Abubakar, S.; Ogbadu, G. H.; Usman, A. B.; Segun, O.; Olorode, O.; Samirah, I. U.

2012-01-01

333

Propagação vegetativa da alfavaca-cravo utilizando diferentes tipos de estacas e substratos / Vegetative propagation of the wild basil using different types of cuttings and substrata  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A propagação vegetativa é considerada importante ferramenta para o melhoramento de espécies lenhosas e herbáceas e vem sendo amplamente utilizada, visando melhorar e manter variedades de importância econômica e medicinal. Neste contexto utilizou-se estacas de alfavaca-cravo de 15 cm para apicais e 2 [...] 5 cm para as medianas, sendo estas com e sem folhas. As estacas foram plantadas em bandejas de isopor de 72 células, utilizando-se 10 substratos. Após 35 dias, as estacas foram retiradas com cuidado, sendo as partes aéreas e radiculares separadas e acondicionadas em saco de papel e mantidas em estufa a 70ºC por 48 h para posterior avaliação da matéria seca. Analisou-se a percentagem de enraizamento, número de folhas na estaca, peso de matéria seca de folha e de raiz. Não houve interação significativa entre os diferentes tipos de substrato e estaca para percentagem de enraizamento, sendo que os substratos de modo geral diferiram pouco entre si. Entre os tipos de estaca destacaram-se para esta variável a mediana sem folha e a apical com folha. Para as demais variáveis houve interação significativa entre o tipo de estaca e o substrato. A melhor estaca foi a mediana sem folhas plantadas em substrato arisco + esterco + húmus e vermiculita nas seguintes proporções: 20%:40%:40%; 40%:20%:40% e 40%:40%. Abstract in english The vegetative propagation is an important tool for the improvement of woody and herbaceous species and could be an important tool to improve and to maintain varieties of economic and medicinal importance. In this experiment cuttings 15 cm long of the apical portion and also 25 cm long cuttings of t [...] he medial portion of the stems, were used both with and without leaves. The cuttings were planted on styrofoam trays with 72 cells, using 10 different substrata. After 35 days, cuttings were carefully removed, the aerial portion being separated from the roots and conditioned in paper bags and maintained in a stove at 70ºC for 48 h, for the dry weight evaluation. There were analyzed the percentage of rooting, number of leaves per cutting and leaf and root dry weight. There was no interaction among substrata and cuttings for the percentage of rooting. Were no significant differences in the rooting among the different substrata used in the experiment there. Better rooting was observed on cuttings from the medial portion of the stem without leaves and from the apical portion with leaves. For the other variables there was significant interaction between the cuttings and the substrata. The cutting that presented best results were those from the medial portion without leaves in the substrata with A+E sandy soil + humus + vermiculite in the following proportions: (20%: 40%:40%); (40%:20%:40%) and (40%:40%:20%) respectively.

Polyana Aparecida D., Ehlert; José Magno Q., Luz; Renato, Innecco.

2004-03-01

334

Propagação vegetativa da alfavaca-cravo utilizando diferentes tipos de estacas e substratos Vegetative propagation of the wild basil using different types of cuttings and substrata  

Directory of Open Access Journals (Sweden)

Full Text Available A propagação vegetativa é considerada importante ferramenta para o melhoramento de espécies lenhosas e herbáceas e vem sendo amplamente utilizada, visando melhorar e manter variedades de importância econômica e medicinal. Neste contexto utilizou-se estacas de alfavaca-cravo de 15 cm para apicais e 25 cm para as medianas, sendo estas com e sem folhas. As estacas foram plantadas em bandejas de isopor de 72 células, utilizando-se 10 substratos. Após 35 dias, as estacas foram retiradas com cuidado, sendo as partes aéreas e radiculares separadas e acondicionadas em saco de papel e mantidas em estufa a 70ºC por 48 h para posterior avaliação da matéria seca. Analisou-se a percentagem de enraizamento, número de folhas na estaca, peso de matéria seca de folha e de raiz. Não houve interação significativa entre os diferentes tipos de substrato e estaca para percentagem de enraizamento, sendo que os substratos de modo geral diferiram pouco entre si. Entre os tipos de estaca destacaram-se para esta variável a mediana sem folha e a apical com folha. Para as demais variáveis houve interação significativa entre o tipo de estaca e o substrato. A melhor estaca foi a mediana sem folhas plantadas em substrato arisco + esterco + húmus e vermiculita nas seguintes proporções: 20%:40%:40%; 40%:20%:40% e 40%:40%.The vegetative propagation is an important tool for the improvement of woody and herbaceous species and could be an important tool to improve and to maintain varieties of economic and medicinal importance. In this experiment cuttings 15 cm long of the apical portion and also 25 cm long cuttings of the medial portion of the stems, were used both with and without leaves. The cuttings were planted on styrofoam trays with 72 cells, using 10 different substrata. After 35 days, cuttings were carefully removed, the aerial portion being separated from the roots and conditioned in paper bags and maintained in a stove at 70ºC for 48 h, for the dry weight evaluation. There were analyzed the percentage of rooting, number of leaves per cutting and leaf and root dry weight. There was no interaction among substrata and cuttings for the percentage of rooting. Were no significant differences in the rooting among the different substrata used in the experiment there. Better rooting was observed on cuttings from the medial portion of the stem without leaves and from the apical portion with leaves. For the other variables there was significant interaction between the cuttings and the substrata. The cutting that presented best results were those from the medial portion without leaves in the substrata with A+E sandy soil + humus + vermiculite in the following proportions: (20%: 40%:40%; (40%:20%:40% and (40%:40%:20% respectively.

Polyana Aparecida D. Ehlert

2004-03-01

335

An Assessment of Mining Activities Impact on Vegetation in Bukuru Jos Plateau State Nigeria Using Normalized Differential Vegetation Index (NDVI  

Directory of Open Access Journals (Sweden)

Full Text Available The study area has a pathetic and deplorable condition of landuse/ landcover. The vegetal cover in the area has to be removed from the activities of tin mining which consequently resulted into adverse environmental effect such as erosion. Different forms of human induced stress such as tin mining and heavy rainfall have severely degraded soils on the Jos Plateau. Such degradation problems are also caused by deforestation, inappropriate farming system, bush burning and over-grazing which are hostile to the environment. The impact of tin mining has greatly affected the natural ecology of the study area Bukuru. Micro and macro organisms and plants have been stripped off their natural habitat due to tin mining activities. This paper therefore, assesses the mining activities impact on the vegetation in Bukuru area of Jos plateau in Nigeria. Normalized Differential Vegetation Index (NDVI techniques was adopted to Maps effect of tin mining on the vegetation for the period between 1975 and 2007 using LandSat satellite data. The result of the differential vegetation index analysis reveals a decline in vegetated surfaces in 1986 ranging from 0.04 to 0.58 indicating 0.05 and continuous loss in vegetation over the study area in 2007 (vegetated surface decrease by 0.08 between 1986 and 2007. The decrease in vegetated surface is due to intensive mining and cultivation.

Musa Haruna D.

2011-11-01

336

Estimating the Maximal Light Use Efficiency for Different Vegetation through the CASA Model Combined with Time-Series Remote Sensing Data and Ground Measurements  

Directory of Open Access Journals (Sweden)

Full Text Available Maximal light use efficiency (LUE is an important ecological index of a vegetation essential attribute, and a key parameter of the LUE-based model for estimating large-scale vegetation productivity by remote sensing technology. However, although currently used in different models there still exists extensive controversy. This paper takes the Zoige Plateau in China as a case area to develop a new approach for estimating the maximal LUEs for different vegetation. Based on an existing land cover map and MODIS NDVI product, the linear unmixing method with a moving window was adopted to estimate the time-series NDVI for different end members in a MODIS NDVI pixel; then Particle Swarm Optimizer (PSO was applied to search for the optimization of LUE retrievals through the CASA (Carnegie-Ames-Stanford Approach model combined with time-series NDVI and ground measurements. The derived maximal LUEs present significant differences among various vegetation types. These are 0.669 gC·MJ?1, 0.450 gC·MJ?1 and 0.126 gC·MJ?1 for the xerophilous grasslands with high, moderate and low vegetation fraction respectively, 0.192 gC·MJ?1 for the hygrophilous grasslands, and 0.125 gC·MJ?1 for the helobious grasslands. The field validation shows that the estimated net primary productivity (NPP by the derived maximal LUE is closely related to the ground references, with R2 of 0.8698 and root-mean-square error (RMSE of 59.37 gC·m?2·a?1. This indicates that the default set in the CASA model is not suitable for NPP estimation for the regional mountain area. The derived maximal LUEs can significantly improve the capability of NPP mapping, and open up the perspective for long-term monitoring of vegetation ecological health and ecosystem productivity by combining the LUE-based model with remote sensing observations.

Ainong Li

2012-12-01

337

Vegetable milks and their fermented derivative products  

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The so-called vegetable milks are in the spotlight thanks to their lactose-free, animal protein-free and cholesterol-free features which fit well with the current demand for healthy food products. Nevertheless, and with the exception of soya, little information is available about these types of milks and their derivatives. The aims of this review, therefore, are to: highlight the main nutritional benefits of the nut and cereal vegetable milks available on the mar...

Neus Bernat; Maite Cháfer; Amparo Chiralt; Chelo González-Martínez

2014-01-01

338

Analysis of the vegetation of the sandstone ridges (IB land type) of the north-eastern parts of the Mapungubwe national Park, Limpopo Province, South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The establishment of the Mapungubwe National Park has been an objective of several conservationists for many years. The ultimate objective is that this park should become a major component of a Transfrontier National Park shared by Botswana, Zimbabwe and South Africa. The aim of this study was to identify, classify and describe the plant communities present in the Ib land type of the park. Sampling was done by means of the Braun-Blanquet method. A total of 48 stratified random relevés were s...

Hugo Beduizenhout; Cilliers, Sarel S.; Gotze, Albie R.; Klaus Kellner

2008-01-01

339

Observing Arctic Ecology using Networked Infomechanical Systems  

Science.gov (United States)

Understanding ecological dynamics is important for investigation into the potential impacts of climate change in the Arctic. Established in the early 1990's, the International Tundra Experiment (ITEX) began observational inquiry of plant phenology, plant growth, community composition, and ecosystem properties as part of a greater effort to study changes across the Arctic. Unfortunately, these observations are labor intensive and time consuming, greatly limiting their frequency and spatial coverage. We have expanded the capability of ITEX to analyze ecological phenomenon with improved spatial and temporal resolution through the use of Networked Infomechanical Systems (NIMS) as part of the Arctic Observing Network (AON) program. The systems exhibit customizable infrastructure that supports a high level of versatility in sensor arrays in combination with information technology that allows for adaptable configurations to numerous environmental observation applications. We observe stereo and static time-lapse photography, air and surface temperature, incoming and outgoing long and short wave radiation, net radiation, and hyperspectral reflectance that provides critical information to understanding how vegetation in the Arctic is responding to ambient climate conditions. These measurements are conducted concurrent with ongoing manual measurements using ITEX protocols. Our NIMS travels at a rate of three centimeters per second while suspended on steel cables that are ~1 m from the surface spanning transects ~50 m in length. The transects are located to span soil moisture gradients across a variety of land cover types including dry heath, moist acidic tussock tundra, shrub tundra, wet meadows, dry meadows, and water tracks. We have deployed NIMS at four locations on the North Slope of Alaska, USA associated with 1 km2 ARCSS vegetation study grids including Barrow, Atqasuk, Toolik Lake, and Imnavait Creek. A fifth system has been deployed in Thule, Greenland beginning in 2012. Once compiled and quality controlled, all of our data are freely available online via the Arctic Observing Network's Advanced Cooperative Arctic Data and Information Service (ACADIS). Here we present some of our findings to show how our results can be advantageous to various disciplines including plant ecology, hydrology, geology, atmospheric sciences, and remote sensing. For instance, we found that albedo decreases with increasing NDVI after initial green-up and loss of dead standing litter (DOY 174-184), displaying an r2 of 0.90 in 2012 at Toolik Lake. This relationship is vital for determining phonological events via remote sensing and understanding the surface energy balance that impacts atmospheric processes, weather and climate, the hydrologic cycle, and ecophysiological progression throughout the short arctic growing season. Scaling these data to larger scales, which is critical to future monitoring of the potential impacts of climate change on arctic vegetation, is facilitated by linkage of measurements along the NIMS transects and manual vegetation measurements in the 1 km2 sample grids with frequent low-altitude aerial photography.

Healey, N. C.; Oberbauer, S. F.; Hollister, R. D.; Tweedie, C. E.; Welker, J. M.; Gould, W. A.

2012-12-01

340

Predicting vegetation-stabilized dune morphology  

Science.gov (United States)

The morphology of vegetation-stabilized dune fields on the North American Great Plains mostly comprises parabolic dunes; stabilized barchan and transverse dunes are rare. One notable exception is the Nebraska Sand Hills (NSH), where massive grass-covered barchan and transverse dunes bear proof of former desert-like conditions. We present a hypothesis from a numerical dune field model to explain the vegetation-stabilized morphology of dunes. The model incorporates a growth curve that preferentially grows vegetation in regions of sediment deposition with a sharp drop in growth at the peak depositional tolerance of vegetation, qualitatively matching biological response to erosion and deposition. Simulations on a range of pre-stabilization dune morphologies, from large closely-spaced transverse dunes to small dispersed barchans, indicate that the stabilized morphology is largely determined by the ratio of slipface deposition rate to peak depositional tolerance of vegetation. Conceptually, slipface deposition rate is related to dune height and celerity. By keeping depositional tolerance constant (representing a constant vegetation type and climate) the model shows that large slow-moving dunes have low slipface deposition rates and essentially 'freeze' in place once vegetation is introduced, retaining their pre-vegetation morphology. Small fast-moving dunes have higher slipface deposition rates and evolve into parabolic dunes. We hypothesize that, when barchan and transverse dunes are subjected to a stabilizing climate shift that increases vegetation growth rate, they retain their pre-stabilization morphology if deposition rates are below the depositional tolerance of stabilizing vegetation, otherwise they become parabolic dunes. This could explain why NSH dunes are stabilized in barchan and transverse morphologies while elsewhere on the Great Plains dune fields are dominated by smaller parabolic dunes.

Barchyn, T.; Hugenholtz, C.

2012-04-01