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1

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

2

The vegetation of Yucca Mountain: Description and ecology  

International Nuclear Information System (INIS)

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

3

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

4

REPEATABILITY OF THE FRENCH HIGHER VEGETATION TYPES ACCORDING  

Directory of Open Access Journals (Sweden)

Full Text Available Higher vegetation types are generally determined by successive approximations and defined by a common consent. Instead, they might be statistically determined and repeated, according to a numerical method called ‘socio-ecology’. This method deals only with floristical data, but gives them an ecological meaning by a previous calibration of the relations between plants, computed as ecological indices. It is applied to a pair of two homologous samples, each having 2.000 relevés and coming from the 60.000 relevés stored in the French data bank ‘Sophy’. Each sample covers the main ecological gradients of the bank, it defines a hierarchy of vegetation types and it explains half the peculiarity of a type with only 10 to 30 discriminant plants, out of the 5.000 plants observed in the relevés. Results : 1 The discriminant plants may characterize the vegetation types, including the higher ones, in a coherent and readable form. 2 In the two independent classifications, having different structures, the same vegetation types are repeated. They are the reciprocal nearest types, in the socio-ecological space. Though the two classifications have no one relevé in common, the repeated types have nearly the same discriminant plants. 3 At the highest level, two clear-cut main types show the difference between light and shadow. The same herbaceous discriminant plants, for a type, and the ligneous or sciaphilous ones, for the other, have similar fidelities and constancies in the two classifications. 4 Such a numerical agreement, instead of common consent, appears again in the sub-types, which remind the classical ones, but which are repeatable.

G. GRANDJOUAN

1998-01-01

5

The ecological cultivation system construction of cucurbits and vegetables in Hainan  

Science.gov (United States)

The application amount of fertilizer and pesticide overall showed rising trends in Hainan. The excessive application of chemical fertilizer and pesticide can cause higher production costs and greater pressure on the ecological environment. The sown area of cucurbits and vegetables showed an increasing trend to a certain extent, safety and pollution-free production of cucurbits and vegetables has become one of the principal contradictions restricting the development of cucurbits and vegetables in Hainan. In this study, the ecological cultivation system of cucurbits and vegetables was constructed combining ecology, ecological economics, and vegetable cultivation principles, which had an important significance for maintaining ecological balance and sustainable development of agriculture.

Liu, Ziji; Yang, Yan

6

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

7

Technology versus Agro-Ecology in Designing Vegetable Production Systems in the Netherlands  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Current open field vegetable production systems in the Netherlands do not meet market and societal demands. These demands could not be fulfilled by adapting current production systems. Other kinds of production systems are needed and therefore two types of systems are designed by 1) a technological and 2) an agro-ecological vision. The technological vision aims at excluding and predicting external influences with the focus on control. Variants of this vision are production systems with fertig...

Haan, J. J.; Sukkel, W.; Stilma, E. S. C.

2010-01-01

8

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

9

NUTRITIONAL STATE OF ECOLOGICAL VEGETABLES IN DROUGHT CONDITIONS  

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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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Ecological characteristics of plankton and aquatic vegetation in Lake Qiluhu.  

Science.gov (United States)

Investigations of the phytoplankton, zooplankton, zoobenthos and aquatic vegetation in Lake Qiluhu were carried out in February, 2009. Over the whole lake, 13 sampling sites were set up for the analysis of phytoplankton and zooplankton, and 22 profiles for the collection of macrophytes and zoobenthos. In the survey, 7 phyla, 65 algae species were identified. The average abundance of phytoplankton was 7.16 × 10(8) cells/L, and the dominant specie was Limnothrix redekei. No obvious surface accumulation of algae was detected. The concentration of Chlorophyll a ranged from 85 to 101 ?g/L, and the average value was 93 ?g/L. Nineteen species of zooplankton were observed, including 4 species of rotifers, 6 species of cladocerans and 9 species of copepods. Copepods were the dominant species, their abundance reaching 68%, whilst Cladocerans took second place with an abundance proportion of 28%. Six species of submerged vegetation were identified: Potamogeton Pectinatus, Myriophyllum, Elodea Canadensis, Ceratophyllum demersum and Potamogeton crispus. Amongst them, the dominant vegetation was P. Pectinatus, the biomass of which was up to 63% of the total biomass. Emerged macrophytes were cluster distributed across the whole lake, mainly consisting of Scirpus tabernaemontani, phragmites communis and cane shoots. Unfortunately, no living zoobenthos were found at the sites. The results indicated that, in Lake Qiluhu, the abundance of phytoplankton was maintained at a high level. The ecological function of submerged vegetation was gradually being lost because of its low standing crop and coverage, and the benthic animal habitat was severely damaged. PMID:24759520

Mingming, Hu; Huaidong, Zhou; Yuchun, Wang; Yingcai, Wang; Zhen, Wang; Weiju, Wu; Gaofeng, Zhao; Yao, Cheng; Yongding, Liu

2014-01-01

11

Snow cover dynamics, soil moisture variability and vegetation ecology in high mountain catchments of central Norway  

Science.gov (United States)

The influence of water balance on vegetation was investigated by measurements of snow cover dynamics and soil moisture variability within small high mountain catchments of central Norway. The challenge of this study is to explain vegetation patterns by means of a functional ecosystem analysis as a basis for regionalization approaches. Results of a process-oriented analysis of factors determining vegetation were based on spatial data from the low- and middle-alpine altitudinal belts. Methods and techniques were combined for mappings and process measurements. Complex data were processed using a database, a geographical information system and multivariate statistics for spatio-temporal analyses. The new outcome of this study is that soil moisture gradients do not primarily determine the distribution of vegetation. Snow cover is important for each catchment but does not explain differences between low- and middle-alpine conditions. Similar snow conditions are correlated with different vegetation types along an altitudinal range. Near-surface temperature conditions have secondary effects on plant species distribution. There is no single significant statistical factor that describes spatial ecological patterns. Only multiple factor groupings can explain the micro-mosaicing of high-mountain landscapes.

Löffler, Jörg

2005-08-01

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Next generation dynamic global vegetation models: learning from community ecology (Invited)  

Science.gov (United States)

Dynamic global vegetation models are a powerful tool to project past, current and future vegetation patterns and the associated biogeochemical cycles. However, most models are limited by their representation of vegetation by using static and pre-defined plant functional types and by their simplistic representation of competition. We discuss how concepts from community assembly theory and coexistence theory can help to improve dynamic vegetation models. We present a trait- and individual-based dynamic vegetation model, the aDGVM2, that allows individual plants to adopt a unique combination of trait values. These traits define how individual plants grow, compete and reproduce under the given biotic and abiotic conditions. A genetic optimization algorithm is used to simulate trait inheritance and reproductive isolation between individuals. These model properties allow the assembly of plant communities that are adapted to biotic and abiotic conditions. We show (1) that the aDGVM2 can simulate coarse vegetation patterns in Africa, (2) that changes in the environmental conditions and disturbances strongly influence trait diversity and the assembled plant communities by influencing traits such as leaf phenology and carbon allocation patterns of individual plants and (3) that communities do not necessarily return to the initial state when environmental conditions return to the initial state. The aDGVM2 deals with functional diversity and competition fundamentally differently from current models and allows novel insights as to how vegetation may respond to climate change. We believe that the aDGVM2 approach could foster collaborations between research communities that focus on functional plant ecology, plant competition, plant physiology and Earth system science.

Scheiter, S.; Higgins, S.; Langan, L.

2013-12-01

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Quantitative evaluation of regional vegetation ecological environment quality by using remotely sensed data over Qingjiang, Hubei  

Science.gov (United States)

Vegetation cover is an important component and the best indication to the region ecological environment. The paper adopts a new method of integrating remote sensing technology and composite index appraisal model based multiple linear regression for quantitatively evaluating the regional vegetation ecological environment quality(VEEQ). This method is different to the traditional ecological environment research methods. It fully utilizes the advantages of quantitatively remote sensing technology, directly extracts the key influencing factors of VEEQ, such as vegetation indices (RVI, NDVI, ARVI, TMG), humidity indices(NDMI, MI, TMW), soil and landform indices(NDSI, TMB, GRABS) as the evaluating parameters from data the Landsat 5/TM remotely sensed images, and then puts these factors mentioned above into the multiple linear regression evaluating model. Ultimately we obtain the VEEQ evaluation rank figure of the experimental field-part of Qingjiang region. The handy multiple linear regression model, is proved to be well fit the experimental field for the vegetation ecological environment evaluation research.

Wang, Cheng; Sun, Yan; Li, Lijun; Zhang, Qiuwen

2007-11-01

14

Vegetation types in coastal Louisiana in 2013  

Science.gov (United States)

During the summer of 2013, the U.S. Geological Survey, Louisiana State University, University of Louisiana at Lafayette, and the Louisiana Department of Wildlife and Fisheries Coastal and Nongame Resources Division jointly completed an aerial survey to collect data on 2013 vegetation types in coastal Louisiana. Plant species were listed and their abundance classified. On the basis of species composition and abundance, each marsh sampling station was assigned a marsh type: fresh, intermediate, brackish, or saline (saltwater) marsh. The current map presents the data collected in this effort.

Sasser, Charles E.; Visser, Jenneke M.; Mouton, Edmond; Linscombe, Jeb; Hartley, Steve B.

2014-01-01

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 is possible to relate animal movement and foraging location to landscape and habitat features and vegetation types. This powerful approach is opening up new opportunities to study the spatial aspects of animal behaviour, especially foraging behaviour, with far greater precision and objectivity than before. Advances in GPS technology now mean that sub-metre precision systems can be used to track animals, extending the range of application of this technology from landscape and habitat scale to paddock and patch scale studies. As well as allowing ecological hypotheses to be empirically tested at the patch scale, the improvements in precision are also leading to the approach being increasing extended from large scale ecological studies to smaller (paddock scale agricultural studies. The use of sub-metre systems brings both new scientific opportunities and new technological challenges. For example, fitting all of the animals in a group with sub-metre precision GPS receivers allows their relative inter-individual distances to be precisely calculated, and their relative orientations can be derived from data from a digital compass fitted to each receiver. These data, analyzed using GIS, could give new insights into the social behaviour of animals. However, the improvements in precision with which the animals are being tracked also needs equivalent improvements in the precision with which habitat and vegetation are mapped. This needs some degree of automation, as vegetation mapping at a fine spatial scale using the traditional manual approach is far too time consuming. This paper explores these issues, discussing new applications as well as approaches to overcoming some of the associated problems.

Steven Mark Rutter

2007-07-01

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Vegetation types and surface soils of the Idaho National Engineering Laboratory site  

International Nuclear Information System (INIS)

In 1956 the newly formed Ecology Branch of the Atomic Energy Commission's (AEC) National Reactor Testing Station (NRTS), now called the Idaho National Engineering Laboratory (INEL), under the Department of Energy, initiated a project, using aerial photos taken in 1949, 1953, and 1954 to prepare a vegetation map of the site. This area was designated a National Environmental Research Park (NERP) in 1975. The first map prepared by N. R. French and Ray McBride was produced in 1958, and differentiated vegetation types on the basis of the two most prominent species of plants occurring in each type. This map gave adequate resolution between major vegetation types only in the complex mosaic of types at the northern end of the site, designating everything else as one homogeneous vegetation classification: Artemisia tridentata (big sagebrush) and Chrysothamnus viscidifluorus (green rabbitbrush). To improve the resolution of the vegetation map and thereby make it more useful in distinguishing habitats in all parts of the site, efforts were immediately begun to reclassify the vegetation types on the basis of the three (instead of two) most prominent species of plants representative of each type. This effort was continued on a low-priority basis for several years. In 1965 a vegetation map, according to the three species designation, was prepared by Ray McBride. The map was never documented in a formal report, but was reproduced in a thesis by Harniss (1968) and was referenced by Harniss and West (1973a) in their outline of the vegetation types of the NRTS. It is the purpose of this report to document the original vegetation type map prepared by the late Ray McBride and to provide general descriptions of the different vegetation types. The map has been revised and redrawn, and is appended to this report. Because vegetation is intimately related to soil development, a preliminary soil type map prepared and discussed by Adrian H. Dahl is included in this report

1978-01-01

17

Mapping and characterizing the vegetation types of the Democratic Republic of Congo using SPOT VEGETATION time series  

Science.gov (United States)

The need for quantitative and accurate information to characterize the state and evolution of vegetation types at a national scale is widely recognized. This type of information is crucial for the Democratic Republic of Congo, which contains the majority of the tropical forest cover of Central Africa and a large diversity of habitats. In spite of recent progress in earth observation capabilities, vegetation mapping and seasonality analysis in equatorial areas still represent an outstanding challenge owing to high cloud coverage and the extent and limited accessibility of the territory. On one hand, the use of coarse-resolution optical data is constrained by performance in the presence of cloud screening and by noise arising from the compositing process, which limits the spatial consistency of the composite and the temporal resolution. On the other hand, the use of high-resolution data suffers from heterogeneity of acquisition dates, images and interpretation from one scene to another. The objective of the present study was to propose and demonstrate a semi-automatic processing method for vegetation mapping and seasonality characterization based on temporal and spectral information from SPOT VEGETATION time series. A land cover map with 18 vegetation classes was produced using the proposed method that was fed by ecological knowledge gathered from botanists and reference documents. The floristic composition and physiognomy of each vegetation type are described using the Land Cover Classification System developed by the FAO. Moreover, the seasonality of each class is characterized on a monthly basis and the variation in different vegetation indicators is discussed from a phenological point of view. This mapping exercise delivers the first area estimates of seven different forest types, five different savannas characterized by specific seasonality behavior and two aquatic vegetation types. Finally, the result is compared to two recent land cover maps derived from coarse-resolution (GLC2000) and high-resolution imagery (Africover).

Vancutsem, C.; Pekel, J.-F.; Evrard, C.; Malaisse, F.; Defourny, P.

2009-02-01

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The vegetation ecology of the Seringveld Conservancy, Cullinan, South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Seringveld Conservancy is situated near Cullinan in an area is that is characterised by deep sandy soils. Sand mining for the building industry has become a major threat to the biodiversity of the area. The flora of the Conservancy is best described as a gradual ecotone between the grassland and savanna biomes. The fist objective of the study is to describe the vegetation of the Seringveld Conservancy, in terms of plant communities, plant species composition, habitat as well as composing ...

2010-01-01

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The vegetation ecology of the Seringveld Conservancy, Cullinan, South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Seringveld Conservancy is situated near Cullinan in an area is that is characterised by deep sandy soils. Sand mining for the building industry has become a major threat to the biodiversity of the area. The flora of the Conservancy is best described as a gradual ecotone between the grassland and savanna biomes. The fist objective of the study is to describe the vegetation of the Seringveld Conservancy, in terms of plant communities, plant species composition, habitat as well as composi...

2010-01-01

20

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

1996-01-01

 
 
 
 
21

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

22

Ecological Studies on the Aquatic Vegetation in North East Nile Delta, Egypt  

Directory of Open Access Journals (Sweden)

Full Text Available The present research comprises an investigation of the vegetation analysis, a quantitative assessment of the soil and water characteristics and an evaluation of the relationship between the major identified vegetation groups and the environmental attributes of the canals, drains and their wet shorelines at four governorates in North East Nile Delta, namely: Damietta, El Dakahlya, El Sharkia and Al Qaliopia. Vegetation, soil and water were sampled in 65 representative stands. The floristic categories, life span and life-forms of the recorded species were described. The soil and water characteristics were determined for each stand. The vegetation analysis was carried out using the multivariate techniques. The classification (TWINSPAN and ordination (DCA techniques of the stands led to recognition of four vegetation groups: group A codominated by Veronica anagallis-aquatica, Potulaca oleracea and Cynodon dactylon, group B codominated by Rumex dentatus, Phragmites australis and Cynodon dactylon, group C codominated by Phragmites australis and Echinochloa stagnina and group D codominated by Phragmites australis and Bolboschoenus glaucus. Canonical Correspondence Analysis (CCA was applied to detect the main environmental factors influencing the vegetation groups. The electrical conductivity, calcium, sodium, potassium, magnesium, total nitrogen, chlorides and bicarbonates are the most effective environmental variables, which showed significant correlations with the first and second ordination axes. Accordingly, these soil and water variables seem to be the major ecological factors control the distribution of vegetation in the study area.

M.E. Abu Ziada

2008-01-01

23

Community Composition of Major Vegetations in the Coastal Area of Al-Uqair, Saudi Arabia in Response to Ecological Variations  

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Full Text Available The vegetation characteristics of Al-Uqair coastal area is the major focus of the present study. The studied area is located 55 miles dues south of Dhahran in the eastern province of Saudi Arabia. Three different localities in the study area were ecologically described. The vegetation parameters of the recorded species including density, frequency and abundance with respect to climate and soil characteristics of each habitat were studied. Recorded species were 29 different species with definite community type representing each locality. The major plant species of the first locality representing Al-Uqair coastal strip are Halopeplis perfoliata, Arthrocnemum macrostachyum and Halocnemum strbilaceum. The second locality is dominated with Suaeda vermiculata while the third locality which represented the inland extension of the study area is dominated with Haloxylon persicum, Salsola maritima, Anabasis setifera and Zygophyllum sp.

Ashraf M. Youssef

2008-01-01

24

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

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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. Resu...

Joanna Kapusta-Duch; Teresa Leszczy?ska; Agnieszka Filipiak-Florkiewicz

2012-01-01

25

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

26

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

27

Effect of vegetation type on throughfall deposition and seepage flux  

International Nuclear Information System (INIS)

This paper compares different vegetation types (coniferous and deciduous forest, grassed and pure heathland) in terms of input (throughfall deposition) and output (seepage flux) in a region with intermediate nitrogen load (±20 kg N ha-1 y-1 via bulk precipitation) in comparable conditions in north Belgium. Coniferous forest (two plots Pinus sylvestris and two plots Pinus nigra) received significantly higher nitrogen and sulphur throughfall deposition than deciduous forest and heathland. Grassed and pure heathland had significantly highest throughfall quantities of Ca2+ and Mg2+, respectively. The observed differences in throughfall deposition between the different vegetation types were not univocally reflected in the ion seepage flux. Considerable seepage fluxes of NO3-, SO42-, Ca2+ and Al(III) were only found under the P. nigra plots. We discuss our hypothesis that the P. nigra forests already evolved to a situation of N saturation, while the other vegetation types did not. - Vegetation type determines the time of onset of nitrogen saturation

2008-05-01

28

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.)

2007-01-01

29

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

30

Ecological Factors Affecting the Distribution of Woody Vegetation Near the Arkansas River, Tulsa County  

Directory of Open Access Journals (Sweden)

Full Text Available Ecological factors affecting plant distribution were studied over different rock strata and slope exposures above the Arkansas River, Tulsa County. Here the Wann sandstone caprock is underlain by the Iola limestone formation. The vegetation was analyzed taxonomically by a complete collection throughout one growing season. Belt transects crossing rock strata on all slope exposures permitted computation of parameters summarized by an Importance Percentage for each woody species. Differences in species populations and degree of mesophytism exist on the slope exposures. Sandstone upland dominants are post and blackjack oaks. Smoke-tree, rare in Oklahoma, and chinquapin oak are closely associated in limestone microhabitats, where each occupies a separate niche. The smoke-tree, of disjunct distribution, appears to be a relict of widespread occurrence in past geologic periods. Its survival with limited ecological amplitude is due to the continuance of the microhabitats to which it is so well adapted.

Anne Wanamnaker Long

2004-12-01

31

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

Directory of Open Access Journals (Sweden)

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

32

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

33

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

34

Characterizing the Seasonal Dynamics of Plant Community Photosynthesis Across a Range of Vegetation Types  

Energy Technology Data Exchange (ETDEWEB)

The seasonal cycle of plant community photosynthesis is one of the most important biotic oscillations to mankind. This study built upon previous efforts to develop a comprehensive framework to studying this cycle systematically with eddy covariance flux measurements. We proposed a new function to represent the cycle and generalized a set of phenological indices to quantify its dynamic characteristics. We suggest that the seasonal variation of plant community photosynthesis generally consists of five distinctive phases in sequence each of which results from the interaction between the inherent biological and ecological processes and the progression of climatic conditions and reflects the unique functioning of plant community at different stages of the growing season. We applied the improved methodology to seven vegetation sites ranging from evergreen and deciduous forests to crop to grasslands and covering both cool-season (vegetation active during cool months, e.g. Mediterranean climate grasslands) and warm-season (vegetation active during warm months, e.g. temperate and boreal forests) vegetation types. Our application revealed interesting phenomena that had not been reported before and pointed to new research directions. We found that for the warm-season vegetation type, the recovery of plant community photosynthesis at the beginning of the growing season was faster than the senescence at the end of the growing season while for the coolseason vegetation type, the opposite was true. Furthermore, for the warm-season vegetation type, the recovery was closely correlated with the senescence such that a faster photosynthetic recovery implied a speedier photosynthetic senescence and vice versa. There was evidence that a similar close correlation could also exist for the cool-season vegetation type, and furthermore, the recovery-senescence relationship may be invariant between the warm-season and cool-season vegetation types up to an offset in the intercept. We also found that while the growing season length affected how much carbon dioxide could be potentially assimilated by a plant community over the course of a growing season, other factors that affect canopy photosynthetic capacity (e.g. nutrients, water) could be more important at this time scale. These results and insights demonstrate that the proposed method of analysis and system of terminology can serve as a foundation for studying the dynamics of plant community photosynthesis and such studies can be fruitful.

Gu, Lianhong [ORNL; Post, Wilfred M [ORNL; Baldocchi, Dennis [University of California, Berkeley; Black, Andy [University of British Columbia, Vancouver; Suyker, A.E., [University of Nebraska, Lincoln; Verma, Shashi [University of Nebraska; Vesala, Timo [University of Helsinki; Wofsy, Steve [Harvard University

2009-01-01

35

Effect of vegetation type on throughfall deposition and seepage flux.  

Science.gov (United States)

This paper compares different vegetation types (coniferous and deciduous forest, grassed and pure heathland) in terms of input (throughfall deposition) and output (seepage flux) in a region with intermediate nitrogen load (+/-20kg Nha(-1)y(-1) via bulk precipitation) in comparable conditions in north Belgium. Coniferous forest (two plots Pinus sylvestris and two plots Pinus nigra) received significantly higher nitrogen and sulphur throughfall deposition than deciduous forest and heathland. Grassed and pure heathland had significantly highest throughfall quantities of Ca(2+) and Mg(2+), respectively. The observed differences in throughfall deposition between the different vegetation types were not univocally reflected in the ion seepage flux. Considerable seepage fluxes of NO(3)(-), SO(4)(2-), Ca(2+) and Al(III) were only found under the P. nigra plots. We discuss our hypothesis that the P. nigra forests already evolved to a situation of N saturation, while the other vegetation types did not. PMID:17942204

De Schrijver, A; Staelens, J; Wuyts, K; Van Hoydonck, G; Janssen, N; Mertens, J; Gielis, L; Geudens, G; Augusto, L; Verheyen, K

2008-05-01

36

Effects of Mixing Interaction Types on Ecological Community Stability  

CERN Document Server

In the last years, a remarkable theoretical effort has been made in order to understand stability and complexity in ecological communities. The non-random structures of real ecological interaction networks has been recognized as one key ingredient contributing to the coexistence between high complexity and stability in real ecosystems. However most of the theoretical studies have considered communities with only one interaction type (either antagonistic, competitive, or mutualistic). Recently it has been proposed a theoretical analysis on multiple interaction types in ecological systems, concluding that: a) Mixture of antagonistic and mutualistic interactions stabilize the system with respect to the less realistic case of only one interaction type; b) Complexity, measured in terms of the number of interactions and the number of species, increases stability in systems with different types of interactions. By introducing new theoretical investigations and analyzing 21 empirical data sets representing mutualisti...

Suweis, Samir; Maritan, Amos

2013-01-01

37

Vegetation  

DEFF Research Database (Denmark)

â?¢ 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%. â?¢ 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. â?¢ 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

38

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

39

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 inattention 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.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.

João Paulo Rodrigues Alves Delfino Barbosa

2012-06-01

40

INFLUENCE OF THE SOIL ON GROWING TYPES OF WOOD VEGETATION  

Directory of Open Access Journals (Sweden)

Full Text Available The article reflects influences of soil conditions on growing types of wood vegetation. The carried-out chemical analyses show quantity of chemical elements which have to arrive to the soil with tree waste, and also acidity of the soil

Irkovsky E. R.

2013-10-01

 
 
 
 
41

Effect of vegetation type on throughfall deposition and seepage flux  

Energy Technology Data Exchange (ETDEWEB)

This paper compares different vegetation types (coniferous and deciduous forest, grassed and pure heathland) in terms of input (throughfall deposition) and output (seepage flux) in a region with intermediate nitrogen load ({+-}20 kg N ha{sup -1} y{sup -1} via bulk precipitation) in comparable conditions in north Belgium. Coniferous forest (two plots Pinus sylvestris and two plots Pinus nigra) received significantly higher nitrogen and sulphur throughfall deposition than deciduous forest and heathland. Grassed and pure heathland had significantly highest throughfall quantities of Ca{sup 2+} and Mg{sup 2+}, respectively. The observed differences in throughfall deposition between the different vegetation types were not univocally reflected in the ion seepage flux. Considerable seepage fluxes of NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, Ca{sup 2+} and Al(III) were only found under the P. nigra plots. We discuss our hypothesis that the P. nigra forests already evolved to a situation of N saturation, while the other vegetation types did not. - Vegetation type determines the time of onset of nitrogen saturation.

Schrijver, A. de [Laboratory of Forestry, Ghent University, Geraardsbergse Steenweg 267, 9090 Gontrode (Belgium)], E-mail: an.deschrijver@ugent.be; Staelens, J.; Wuyts, K. [Laboratory of Forestry, Ghent University, Geraardsbergse Steenweg 267, 9090 Gontrode (Belgium); Hoydonck, G. van [Haskoning Belgium BVBA, Hanswijkdries 80, 2800 Mechelen (Belgium); Janssen, N. [Natuurpunt, Coxiestraat 11, 2800 Mechelen (Belgium); Mertens, J.; Gielis, L. [Laboratory of Forestry, Ghent University, Geraardsbergse Steenweg 267, 9090 Gontrode (Belgium); Geudens, G. [Laboratory of Forestry, Ghent University, Geraardsbergse Steenweg 267, 9090 Gontrode (Belgium); Haskoning Belgium BVBA, Hanswijkdries 80, 2800 Mechelen (Belgium); Augusto, L. [UMR-TCEM, INRA-Bordeaux, 71 Avenue Edouard Bourlaux, 33883 Villenave d' Ornon Cedex (France); Verheyen, K. [Laboratory of Forestry, Ghent University, Geraardsbergse Steenweg 267, 9090 Gontrode (Belgium)

2008-05-15

42

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

43

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.

44

Mapping ecosystem types by means of ecological species groups  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A method is presented to deduce nation-wide maps of ecosystem types from FLORBASE. This national database contains data, per km2, on the presence of indigenous plant species that grow in the wild. The ecosystem types on the maps are defined on the basis of abiotic factors that determine the plant species composition of the vegetation in the Netherlands: salinity, moisture regime, nutrient availability, acidity. Water management measures may cause changes in these four factors and, as a result...

2000-01-01

45

Iron Ore Industry Emissions as a Potential Ecological Risk Factor for Tropical Coastal Vegetation  

Science.gov (United States)

In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO2 originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.

Kuki, Kacilda N.; Oliva, Marco A.; Pereira, Eduardo G.

2008-07-01

46

Iron ore industry emissions as a potential ecological risk factor for tropical coastal vegetation.  

Science.gov (United States)

In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO(2) originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk. PMID:18320266

Kuki, Kacilda N; Oliva, Marco A; Pereira, Eduardo G

2008-07-01

47

Phenological characteristics of the main vegetation types on the Tibetan Plateau based on vegetation and water indices  

Science.gov (United States)

Plant phenology is considered one of the most sensitive and easily observable natural indicators of climate change, though few studies have focused on the heterogeneities of phenology across the different vegetation types. In this study, we tried to find the phenological characteristics of the main vegetation types on the Tibetan Plateau. MCD12Q1 images over the Tibetan Plateau from 2001 to 2010 were used to extract the main vegetation types. The Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Land Surface Water Index (LSWI) were calculated using surface reflectance values from the blue, red, near-infrared, short-wave infrared (SWIR) 6 (for LSIW6), and SWIR7 (for LSIW7) bands derived from MOD09A1 and used to explore the phenological characteristics of the main vegetation types on the Tibetan Plateau. The results showed that there were eight constant vegetation types on the Tibetan Plateau from 2001 to 2010 demonstrating multiple phenological characteristics. Evergreen needleleaf forest, evergreen broadleaf forest, and permanent wetland had the minimum NDVI values during the summer season, while open shrubland and grassland had the maximum NDVI/EVI values during this period. NDVI and EVI of cropland/natural vegetation had two peaks for their seasonal variations. EVI showed a more significant correlation with LSWI6/LSWI7 than NDVI. Compared to LSWI7, larger EVI values occurred in evergreen needleleaf forest, evergreen broadleaf forest, mixed forest, and permanent wetland, while smaller values occurred in shrubland and barren or sparsely vegetated cover, and nearly equal values occurred in grassland and cropland.

Peng, D. L.; Zhou, B.; Li, C. J.; Huang, W. J.; Wu, Y. P.; Yang, X. H.

2014-03-01

48

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

49

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.

2011-10-01

50

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.

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

51

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

52

Satellite observations of high northern latitude vegetation productivity changes between 1982 and 2008: ecological variability and regional differences  

International Nuclear Information System (INIS)

To assess ongoing changes in high latitude vegetation productivity we compared spatiotemporal patterns in remotely sensed vegetation productivity in the tundra and boreal zones of North America and Eurasia. We compared the long-term GIMMS (Global Inventory Modeling and Mapping Studies) NDVI (Normalized Difference Vegetation Index) to the more recent and advanced MODIS (Moderate Resolution Imaging Spectroradiometer) NDVI data set, and mapped circumpolar trends in a gross productivity metric derived from the former. We then analyzed how temporal changes in productivity differed along an evergreen-deciduous gradient in boreal Alaska, along a shrub cover gradient in Arctic Alaska, and during succession after fire in boreal North America and northern Eurasia. We find that the earlier reported contrast between trends of increasing tundra and decreasing boreal forest productivity has amplified in recent years, particularly in North America. Decreases in boreal forest productivity are most prominent in areas of denser tree cover and, particularly in Alaska, evergreen forest stands. On the North Slope of Alaska, however, increases in tundra productivity do not appear restricted to areas of higher shrub cover, which suggests enhanced productivity across functional vegetation types. Differences in the recovery of post-disturbance vegetation productivity between North America and Eurasia are described using burn chronosequences, and the potential factors driving regional differences are discussed.

2011-10-01

53

Satellite observations of high northern latitude vegetation productivity changes between 1982 and 2008: ecological variability and regional differences  

Energy Technology Data Exchange (ETDEWEB)

To assess ongoing changes in high latitude vegetation productivity we compared spatiotemporal patterns in remotely sensed vegetation productivity in the tundra and boreal zones of North America and Eurasia. We compared the long-term GIMMS (Global Inventory Modeling and Mapping Studies) NDVI (Normalized Difference Vegetation Index) to the more recent and advanced MODIS (Moderate Resolution Imaging Spectroradiometer) NDVI data set, and mapped circumpolar trends in a gross productivity metric derived from the former. We then analyzed how temporal changes in productivity differed along an evergreen-deciduous gradient in boreal Alaska, along a shrub cover gradient in Arctic Alaska, and during succession after fire in boreal North America and northern Eurasia. We find that the earlier reported contrast between trends of increasing tundra and decreasing boreal forest productivity has amplified in recent years, particularly in North America. Decreases in boreal forest productivity are most prominent in areas of denser tree cover and, particularly in Alaska, evergreen forest stands. On the North Slope of Alaska, however, increases in tundra productivity do not appear restricted to areas of higher shrub cover, which suggests enhanced productivity across functional vegetation types. Differences in the recovery of post-disturbance vegetation productivity between North America and Eurasia are described using burn chronosequences, and the potential factors driving regional differences are discussed.

Beck, Pieter S A; Goetz, Scott J, E-mail: pbeck@whrc.org [Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540 (United States)

2011-10-15

54

Differences in resistance of three subtropical vegetation types to experimental trampling.  

Science.gov (United States)

Experimental trampling trials using a standardized methodology were undertaken in 10 replicate blocks in three vegetation types in an urban reserve in the subtropics of Australia. In each block different intensities of trampling (controls, 10, 25, 50, 100, 150, 200, 250, 300, 400 and 500 passes) were applied, and vegetation parameters were measured pre-trampling, immediately after trampling and 2 weeks later. A Fern understorey had low resistance to trampling intensity, with reductions in relative vegetation height and cover with as few as 10 passes. A Tussock grass understorey showed moderate resistance with reduction in height at 25 passes and cover at 50 passes. A Disturbed grassland dominated by lawn grasses had the highest resistance, with reductions in vegetation height at 100 passes, but cover was affected by as few as 10 passes. The resistance indices (number of passes required to reduce vegetation cover by 50%) of three vegetation types were 210, 360 and 860 passes, respectively. When these values were compared with those for 52 other vegetation types considerable variation was found within life forms, climatic zones and vegetation types indicating that the response of a specific community may not always be predictable. PMID:18799252

Hill, Rachel; Pickering, Catherine

2009-02-01

55

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 vegetati...

2012-01-01

56

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...

2011-01-01

57

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

58

Bayesian classification of vegetation types with Gaussian mixture density fitting to indicator values  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Question: Is it possible to mathematically classify relevés into vegetation types on the basis of their average indicator values, including the uncertainty of the classification? Location: The Netherlands. Method: A large relevé database was used to develop a method for predicting vegetation types based on indicator values. First, each relevé was classified into a phytosociological association on the basis of its species composition. Additionally, mean indicator values for moisture, nutrie...

Witte, J. P. M.; Wo?jcik, R.; Torfs, P. J. J. F.; Haan, M. W. H.; Hennekens, S. M.

2007-01-01

59

Spreading Topsoil Encourages Ecological Restoration on Embankments: Soil Fertility, Microbial Activity and Vegetation Cover  

Science.gov (United States)

The construction of linear transport infrastructure has severe effects on ecosystem functions and properties, and the restoration of the associated roadslopes contributes to reduce its impact. This restoration is usually approached from the perspective of plant cover regeneration, ignoring plant-soil interactions and the consequences for plant growth. The addition of a 30 cm layer of topsoil is a common practice in roadslope restoration projects to increase vegetation recovery. However topsoil is a scarce resource. This study assesses the effects of topsoil spreading and its depth (10 to 30 cm) on two surrogates of microbial activity (?-glucosidase and phosphatase enzymes activity and soil respiration), and on plant cover, plant species richness and floristic composition of embankment vegetation. The study also evaluates the differences in selected physic-chemical properties related to soil fertility between topsoil and the original embankment substrate. Topsoil was found to have higher values of organic matter (11%), nitrogen (44%), assimilable phosphorous (50%) and silt content (54%) than the original embankment substrate. The topsoil spreading treatment increased microbial activity, and its application increased ?-glucosidase activity (45%), phosphatase activity (57%) and soil respiration (60%). Depth seemed to affect soil respiration, ?-glucosidase and phosphatase activity. Topsoil application also enhanced the species richness of restored embankments in relation to controls. Nevertheless, the depth of the spread topsoil did not significantly affect the resulting plant cover, species richness or floristic composition, suggesting that both depths could have similar effects on short-term recovery of the vegetation cover. A significant implication of these results is that it permits the application of thinner topsoil layers, with major savings in this scarce resource during the subsequent slope restoration work, but the quality of topsoil relative to the original substrate should be previously assessed on a site by site basis.

Rivera, Desiree; Mejias, Violeta; Jauregui, Berta M.; Lopez-Archilla, Ana Isabel; Peco, Begona

2014-01-01

60

Investigation of Soil Properties effects on Establishment of Vegetation Types (Case Study: Sabzdasht, Bafgh)  

Science.gov (United States)

This research was conducted to investigate the relationships between soil (Organic Matter, potassium, phosphorous, sodium, Fine gravel, soil texture, EC, Lime, Gypsum, Nitrogen) and environmental (Elevation, Slope) factors with distribution of vegetation types in rangelands of Sabzdasht, located in Bafgh, Yazd province at 2012. For this purpose, four vegetation types were selected as follows: Artemisia sieberi; Artemisia sieberi, Stipa barbata, Eurotia ceratoides; Dorema ammoniacum, Artemisia sieberi, Eurotia ceratoides; and Hammada salicornica.Minimal area was determined using nested plots. Afterward, vegetation factors were measured and five soil profiles were dug randomly in minimal area. In each profile, data for depths of 0-10 and 10-80 cm were recorded. Principal Component Analysis was applied to analyze the data. Results showed that soil texture, potassium, phosphorous, EC and lime had the most impact on variation and distribution of vegetation types. Keywords: Environmental Factors, Principal Component Analysis, Minimal Area, Bafgh, Yazd

Sadeghi Nia, Majid; jafari, Mohammad; Zahedi Amiri, Ghavomoldin; Baghestani Maybodi, Naser; Tavili, Ali

2013-04-01

 
 
 
 
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

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

64

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. 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)

1982-05-10

65

Diversity in a complex ecological network with two interaction types.  

Czech Academy of Sciences Publication Activity Database

. Ro?. 118, ?. 1 (2009), s. 122-130. ISSN 0030-1299Grant CEP: GA AV ?R IAA100070601Grant ostatní: University of California(US) DEB-0553768; The Spanish Ministry of Science and Technology(ES) REN2003-04774; The Spanish Ministry of Science and Technology(ES) REN2003-00273Výzkumný zám?r: CEZ:AV0Z50070508Klí?ová slova: complex ecological networkKód oboru RIV: EH - Ekologie - spole?enstvaImpakt faktor: 3.147, rok: 2009

Melián, C. J.; Bascompte, J.; Jordano, P.; K?ivan, Vlastimil

66

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

67

An ecological study of the major vegetation communities of the Vaalbos National Park, Northern Cape. 1. The Than-Droogeveld section  

Directory of Open Access Journals (Sweden)

Full Text Available A detailed classification, description and mapping of the Than-Droogeveld section of the Vaalbos National Park, Northern Cape Province, were initiated. This classification is intended to serve as an ecological basis for the establishment of an efficient wildlife management programme as well as conservation policies for the Vaalbos National Park. Using a numerical classification technique (TWINSPAN as a first approximation, the classification was refined by applying Braun-Blanquet procedures. A hierarchical classification, as well as description, ecological interpretation and a vegetation map are presented. In the phytosociological table 11 major plant communities are recognised.

H. Bezuidenhout

1994-09-01

68

Ecological studies of the solfatara vegetation on Mt. Zao, NE Japan  

Energy Technology Data Exchange (ETDEWEB)

The vegetation, soil, and the nutrient content of plants were studied in and around the solfataras of Mt. Zao (NE Japan). Certain plant communities, including Carex angustisquama, Deschamsia flexuosa, Polygonum sachalinense, P. sachalininse-Miscanthus sinensis, and M. sinensis were recognized near all solfataras studied. The communities of Empetrum nigrum var. japonicum, Ledum palustre var. diversipilosum, Menziesia multiflora, Sasa kurilensis, and Polygonum japonica var. colorans were restricted to the area of those solfataras which were at high altitudes. The Clethra berbinervis community was restricted to low altitudes. The solfatara soils were strongly acidic, poor in nutrients, and had high concentrations of exchangeable sulfuric anion. They were especially poor in available solfatara soils and normal climax soils. The concentration of S, P, Ca, and K in the Carex a., Deschampsia f., Polygonum s., and Miscantha s. were directly proportional to their proximity to the solfataras. Those in Sasa k., Hydrangea paniculata, and Clethra b. were not affected by the habitat. The needles of Abies mariesii in the vicinity of solfataras accumulated sulfur to the extent that they suffered early defoliation.

Saito, K. (Dept. of Biol., Fac. of Gen. Ed., Yamagata Univ., Japan); Kawai, Y.; Abe, H.

1976-02-01

69

Present and Historical Climate Variability and its Ecological Impact on Vegetation in South West England  

Science.gov (United States)

West Cornwall is the most south westerly part of the United Kingdom with a strong maritime climate. This study analyses the earliest archived instrumental meteorological records collected in West Cornwall (SW England). Records were obtained from the Met Office archive (Camborne 1957-2010; Culdrose 1985-2011), Trengwainton Garden (1940-2010), and from the Royal Cornwall Polytechnic Society, data for Falmouth (1880-1952) and Helston (1843-1888). Homogeneity tests were used (Levene and Brown-Forsythe tests) to exclude any trends not related to climate variability. The data exhibit trends in annual mean and maximum temperatures over the timescales analysed, and show a general temperature increase in the 20th and 21st century. Annual and seasonal temperature changes are found to vary locally with strongly positive trends in autumn, spring and summer seasons. Trends in precipitation are positive only for the 19th century and only for one station. Correlation with the North Atlantic Oscillation (NAO) index shows negative results for precipitation data. However correlation with the NAO index is positive with temperature, especially in the winter season. Return period analysis showed a decrease in intensity and frequency of extreme precipitation events in the post-1975 period (Camborne and Trengwainton Garden stations). Climate change in the 20th century, and future continued warming is likely to have major implications on biodiversity in this region. The second part of this research analyses changes in the geographical distribution of plant species over West Cornwall using herbarium and current vegetation records. Also we examine whether Ellenberg values could be used as an environmental change indicator. This research will clearly contribute to a better identification of the climate change impact in West Cornwall, but will also benefit policy developing strategies to identify areas at risk of climate impacts at the regional and local scale.

(Sasha) Kosanic, Aleksandra; Harrison, Stephan; Anderson, Karen; Turkington, Thea

2014-05-01

70

The effect of storm sequence, catchment structure, vegetation type and antecedent moisture conditions on nutrient loading and stream discharge for a small Catskill mountain watershed  

Science.gov (United States)

Research suggests that among the possible consequences of climate change could be a change in the spatio-temporal pattern of precipitation within and across years. In particular, it is suggested that changes in inter-storm period, storm depth and the partitioning of precipitation between rain and snow events could occur. A complex interaction exists between precipitation, topographic controls, catchment structure and vegetation type and status. Collectively, they define a spatial pattern of antecedent moisture conditions across the landscape prior to each precipitation event, which in turn significantly impacts stream flow characteristics such as base flow, storm flow and nutrient loading. In the present study, we use a spatially distributed hydro-ecological model (RHESSys) to model the change in the relative contribution of stream flow and nutrient loading from sub-catchments within Biscuit Brook (Catskill mountains, New York, USA) as a function of precipitation pattern and vegetation cover. Specifically, we investigate how the spatial pattern of antecedent moisture conditions within each sub-catchment varies as a function of modeled vegetation type and precipitation pattern, and how the aggregate response of the catchment changes in terms of base flow, storm flow and nutrient loading. Implications for water quality and water quality management are assessed and discussed. Key words: climate change, RHESSys, stream discharge, nutrient loading, watershed modeling, ecological modeling, water quality

Randolph, A.; Schneiderman, E. M.; Pierson, D. C.; Zion, M. S.; Band, L. E.

2013-12-01

71

Soil Respiration Responses to Variation in Temperature Treatment and Vegetation Type  

Science.gov (United States)

Complex linkages exist between terrestrial vegetation, soil moisture, soil organic matter (SOM), local climate, and soil microorganisms. Thus, large-scale changes in vegetation, such as the woody plant encroachment observed in many historically semiarid and arid grasslands worldwide, could potentially alter the flux of carbon from soil reserves to the atmosphere. Mathematical models that attempt to project the long-term impact of vegetative shifts on soil fluxes largely rely on assumptions such as first-order donor control rather than incorporate the biological aspects of soil respiration such as microbial activity. To examine the impact of vegetation type on soil physicochemical properties and soil microbial respiration and provide experimental data to refine existing predictive models, we compared soil (ground basalt from northern Arizona) in mesocosms established with no vegetation, velvet mesquites (Prosopis velutina; woody shrub), or sideoats gramas (Bouteloua curtipendula; grass) for 2 years, The temperature sensitivity of soil respiration was examined by incubating soil (0-10 and 10-30 cm depth fractions) from each vegetation treatment at 10, 20, 30, and 40 °C for 24 hours. Vegetated soils contained more SOM (~0.1% for mesquite and grass mesocosms) than non-vegetated soils (~0.02%). Respiration rates were generally highest from grass-established soils, intermediate from mesquite-established soils, and lowest from non-vegetated soils. Respiration rates of samples incubated without the addition of substrate peaked at approximately 30 °C, whereas respiration rates of samples incubated with dextrose were highest at 40 °C. Further, the respiration assays suggest that while respiration rates are overall higher in grass-established soils, mesquite-established soils are more temperature sensitive which may have significant implications in the context of global warming and current fire management practices.

Liu, S.; Pavao-zuckerman, M.

2013-12-01

72

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

73

Simulating fire-induced ecological succession with the dynamically coupled fire-vegetation model, ED-SPIFTIRE  

Science.gov (United States)

The simulation of fire-vegetation feedbacks is crucial for determining fire-induced changes to ecosystem structure and function, and emissions of trace gases and aerosols under future climate change. A new global fire model SPITFIRE (SPread and InTensity of FIRE) has been designed to overcome many of the limitations in existing fire models set within DGVM frameworks (Thonicke et al. 2008). SPITFIRE has been applied in coupled mode globally (Thonicke et al. 2008) and northern Australia (Spessa et al. unpubl.) as part of the LPJ DGVM. It has also been driven with MODIS burnt area data applied to sub-Saharan Africa (Lehsten et al. 2008) as part of the LPJ-GUESS vegetation model (Smith et al. 2001). Recently, Spessa & Fisher (unpubl.) completed the coupling of SPIFTIRE to the Ecosystem Demography (ED) model (Moorecroft et al. 2001), which has been globalised by Dr R. Fisher as part of the development of the new land surface scheme JULES (Joint UK Environment Simulator) within the QUEST Earth System Model (http://www.quest-esm.ac.uk/). In contrast to the LPJ DGVM, ED is a ‘size and age structured' approximation of an individual based gap model. The major innovation of the ED-SPITFIRE model compared with LPJ-SPITFIRE is the categorisation of each climatic grid cell into a series of non-spatially contiguous patches which are defined by a common ‘age since last disturbance'. In theory, the age-class structure of ED facilitates ecologically realistic processes of succession and re-growth to be represented. By contrast, LPJ DGVM adopts an ‘area-based approach' that implicitly averages individual and patch differences across a wider area and across ‘populations' of PFTs. This presentation provides an overview of SPITFIRE, and provides preliminary results from ED-SPITFIRE applied to northern Australian savanna ecosystems which, due to spatio-temporal variation in fire disturbance, comprise a patchwork of grasses and trees at different stages of post-fire succession. Comparisons with similar simulations undertaken with LPJ-SPITFIRE are also presented.

Spessa, A.; Fisher, R.

2009-04-01

74

Increase of productivity of vegetables grown in winter-type greenhouses by means of radiation stimulation  

International Nuclear Information System (INIS)

Experiments on vegetables grown in winter-type greenhouses have been carried out. Optimum doses which cause the greatest stimulation effect during pre-sowing gamma irradiation are established. These doses vary from 0.5 to 8 krad for cabbage, from 0.1 to 3 krad for radish, from 0.1 to 2 krad for lattuce, and from 0.1 to 0.25 krad for leek. The increase in the output of trade production for all vegetable cultures studied is 15-20 %

1979-01-01

75

An ecological study of the major vegetation communities of the Vaalbos National Park, Northern Cape. 2. The Graspan-Holpan section  

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Full Text Available Detailed classification, description and mapping of the Graspan-Holpan section of the Vaalbos National Park, Northern Cape, were initiated. This classification is intended to serve as a basis for the establishment of an efficient wildlife management programme as well as conservation policies for the Vaalbos National Park. Using a numerical classification technique (TWINSPAN as a first approximation, the classification was refined by applying Braun-Blanquet procedures. A hierarchical plant community clas- sification, description, ecological interpretation and a vegetation map are presented. In the phytosociological table nine major plant communities are recognised.

H. Bezuidenhout

1995-09-01

76

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+/-0.001, 0.0018+/-0.0002, and 0.0012+/-0.0001 mol C/mol 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.

Huemmrich, Karl F.; Gamon, John; Tweedie, Craig; Campbell, Petya K.; Landis, David R.; Middleton, Elizabeth M.

2013-01-01

77

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

78

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

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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

79

[Spatial neighboring characteristics among patch types in oasis and its ecological security].  

Science.gov (United States)

In this paper, the spatial neighboring length and number between oasis types and desert or salina-marsh in the Jinta Oasis located in the arid Heihe River Basin of Northwest China were calculated by using ArcView3.0a and buffer zone analysis methods, and the threatening degree of oasis ecological security was discussed. The results indicated that it was different in neighboring length and number between oasis types and desert or salina-marsh, and the influencing area by desert and salina-marsh patches was also different. Grassland and farmland had more neighboring length and numbers with desert or salina-marsh patches, and impacted by desertification seriously. Forest and farmland had more length and numbers adjacent to salina-marsh, and influenced by salinization severely. The assessment of ecological security based on spatial analysis could reveal the threatening degree of oasis by desertification and salinization. PMID:15139182

Jiao, Yuanmei; Xiao, Duning

2004-01-01

80

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

 
 
 
 
81

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

82

[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

83

Dung beetle assemblage structure in Tswalu Kalahari Reserve: responses to a mosaic of landscape types, vegetation communities, and dung types.  

Science.gov (United States)

Tswalu Kalahari Reserve is a private game reserve covering 1,020 km(2) in the Northern Cape, South Africa. It has been created from a number of reclaimed farms and restocked with large indigenous mammals. Two surveys were conducted to inventory the dung beetle fauna (Coleoptera: Scarabaeidae: Scarabaeinae) and determine their spatial patterns and food type associations. The spatial survey used pig dung-baited pitfall traps to examine dung beetle distribution across three main landscape types (plains, dunes, hills) comprising six principal vegetation communities. The food study examined their relative associations with carrion and four different dung types within a single vegetation community. A total of 70 species was recorded. Because the food association study was spatially restricted and conducted under drought conditions, abundance and species richness (47 species) were much lower than in the spatial study (64 species), which was conducted after substantial rainfall. Principal spatial differences in species abundance structure of assemblages were between the sandy southwest plains and dunes; the sandy northern dune fields and plains; and the rocky hills. Forty species analyzed in the food association study showed clear distributional biases to carrion or the dung of elephant (monogastric herbivore), pig (omnivore), cattle and sheep (ruminant herbivores), or pig and cattle. The results (1) show how dung beetle assemblage structure is locally diversified across the heterogeneous landscape of the reserve and (2) indicate how the different dung types dropped by a diverse assemblage of indigenous mammals may variously favor different species of dung beetles. PMID:20550793

Davis, Adrian L V; Scholtz, Clarke H; Kryger, Ute; Deschodt, Christian M; Strümpher, Werner P

2010-06-01

84

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.

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

2014-02-01

85

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

86

Major vegetation types of the Soutpansberg Conservancy and the Blouberg Nature Reserve, South Africa  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english The Major Megetation Types (MVT) and plant communities of the Soutpansberg Centre of Endemism are described in detail, with special reference to the Soutpansberg Conservancy and the Blouberg Nature Reserve. Phytosociological data from 442 sample plots were ordinated using a DEtrended CORrespondence [...] ANAlysis (DECORANA) and classified using TWo-Way INdicator SPecies ANalysis (TWINSPAN). The resulting classification was further refined with table-sorting procedures based on the Braun-Blanquet floristic-sociological approach of vegetation classification using MEGATAB. Eight MVT's were identified and described as Eragrostis lehmanniana var. lehmanniana-Sclerocarya birrea subsp. caffra Blouberg Northern Plains Bushveld, Euclea divinorum-Acacia tortilis Blouberg Southern Plains Bushveld, Englerophytum magalismontanum-Combretum molle Blouberg Mountain Bushveld, Adansonia digitata-Acacia nigrescens Soutpansberg Arid Northern Bushveld, Catha edulis-Flueggia virosa Soutpansberg Moist Mountain Thickets, Diplorhynchus condylocarpon-Burkea africana Soutpansberg Leached Sandveld, Rhus rigida var. rigida-Rhus magalismontanum subsp. coddii Soutpansberg Mistbelt Vegetation and Xymalos monospora-Rhus chirendensis Soutpansberg Forest Vegetation.

Mostert, Theo H.C.; Bredenkamp, George J.; Klopper, Hannes L.; Verwey, Cornie; Mostert, Rachel E.; Hahn, Norbert.

87

Major Vegetation Types of the Soutpansberg Conservancy and the Blouberg Nature Reserve, South Africa  

Directory of Open Access Journals (Sweden)

Full Text Available The Major Megetation Types (MVT and plant communities of the Soutpansberg Centre of Endemism are described in detail, with special reference to the Soutpansberg Conservancy and the Blouberg Nature Reserve. Phytosociological data from 442 sample plots were ordinated using a DEtrended CORrespondence ANAlysis (DECORANA and classified using TWo-Way INdicator SPecies ANalysis (TWINSPAN. The resulting classification was further refined with table-sorting procedures based on the Braun–Blanquet floristic–sociological approach of vegetation classification using MEGATAB. Eight MVT’s were identified and described as Eragrostis lehmanniana var. lehmanniana–Sclerocarya birrea subsp. caffra Blouberg Northern Plains Bushveld, Euclea divinorum–Acacia tortilis Blouberg Southern Plains Bushveld, Englerophytum magalismontanum–Combretum molle Blouberg Mountain Bushveld, Adansonia digitata–Acacia nigrescens Soutpansberg Arid Northern Bushveld, Catha edulis–Flueggia virosa Soutpansberg Moist Mountain Thickets, Diplorhynchus condylocarpon–Burkea africana Soutpansberg Leached Sandveld, Rhus rigida var. rigida–Rhus magalismontanum subsp. coddii Soutpansberg Mistbelt Vegetation and Xymalos monospora–Rhus chirendensis Soutpansberg Forest Vegetation.

Rachel E. Mostert

2008-05-01

88

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

89

Classification of the vegetation of the Ba land type in the Mooi River catchment area, Transvaal Die plantgemeenskappe van die Ba-landtipe in die Mooirivieropvanggebied, Transvaal  

Directory of Open Access Journals (Sweden)

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 Ba land type. Six plant communities were successfully distinguished through applying a numerical classification (TWINSPAN 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 (DECORANA. The studv 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 am hoofplantegroei-eenhede en hulle variasies — van die Ba-landtipe — te identifiseer,karakteriseer en aan die hand van die habitat ekologies te interpreteer. Ses plantgemeenskappe is deur toepassing van ’n numeriese klassifikasie (TWINSPAN en Braun-Blanquet-prosedures geïdentifiseer 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 ordeningstegniek (DECORANA geïdentifiseer. Die studie beklemtoon die belangrikheid van topografie en grondtipe vir die afbakening van plantegroei-bestuurseenhede vir boerdery of natuurbewaring.

H. Bezuidenhout

1991-07-01

90

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

Directory of Open Access Journals (Sweden)

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

91

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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 gre [...] en 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 and sucrose contents decreased after the first day of storage at 30ºC. There was no difference in trypsin inhibitor activity until 6 d of storage at 30 and 7ºC. The green color of the pods that was an indication of the quality that was maintained when stored at 7ºC during 3 d. To preserve the quality of vegetable-type soybean, pods should be stored at 30ºC and consumed within 24 h or stored at 7ºC for up to 3 d of storage.

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

92

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 and sucrose contents decreased after the first day of storage at 30ºC. There was no difference in trypsin inhibitor activity until 6 d of storage at 30 and 7ºC. The green color of the pods that was an indication of the quality that was maintained when stored at 7ºC during 3 d. To preserve the quality of vegetable-type soybean, pods should be stored at 30ºC and consumed within 24 h or stored at 7ºC for up to 3 d of storage.

Andréia Cristina Santana

2012-08-01

93

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.

94

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

Energy Technology Data Exchange (ETDEWEB)

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 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.

Walker, D A; Bhatt, U S; Raynolds, M K; Romanovsky, V E [University of Alaska Fairbanks, Fairbanks, AK (United States); Leibman, M O; Gubarkov, A A; Khomutov, A V; Moskalenko, N G; Orekhov, P; Ukraientseva, N G [Earth Cryosphere Institute, Russian Academy of Science, Siberian Branch, Tyumen (Russian Federation); Epstein, H E; Yu, Q [University of Virginia, Charlottesville, VA (United States); Forbes, B C; Kaarlejaervi, E [Arctic Center, University of Lapland, Rovaniemi (Finland); Comiso, J C [NASA Goddard Space Flight Center, MD (United States); Jia, G J [Chinese Academy of Sciences, Institute for Atmospheric Physics, Beijing (China); Kaplan, J O [Swiss Federal Institute for Forest Snow and Landscape Research, Birmensdorf (Switzerland); Kumpula, T [University of Joensuu, Joensuu (Finland); Kuss, P [University of Berne, Berne (Switzerland); Matyshak, G [Moscow State University, Moscow (Russian Federation)

2009-10-15

95

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 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.

2009-10-01

96

Relationship of young-of-the-year northern pike to aquatic vegetation types in backwaters of the upper Mississippi River  

Science.gov (United States)

The association of young-of-the-year northern pike (Esox lucius) with different aquatic plant types (e.g., submerged, emergent, floating) was studied to evaluate the impacts of a potential loss of backwaters on available fish nursery habitats in the upper Mississippi River. Eight biweekly collections were made at each of six representative lentic habitats in Navigation Pool 7. In the spring, average catches of northern pike from areas with submerged vegetation were nearly three times greater than from areas with emergent vegetation, and more than 10 times greater than from an area with no vegetation. This pattern was consistent until late summer, when the young became more common in the more highly oxygenated, less heavily vegetated waters. Food and growth were examined as possible indicators for the selection of areas with submerged vegetation over other habitats. Food varied among fish in the different vegetation types; however, no significant patterns of improved growth or condition were apparent. Young northern pike apparently were successful, opportunistic feeders. Although preference for habitats with submerged vegetation was seemingly not related to food, the overall production of young was clearly best in these habitats.

Holland, L. E.; Huston, M. L.

1984-01-01

97

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

Science.gov (United States)

Background 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 red beans intake and OR = 7.1; 95% CI: 2.3–22.2; P 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.

Mvitu, Moise; Longo-Mbenza, Benjamin; Tulomba, Dieudonne; Nge, Augustin

2012-01-01

98

Type of vegetable oils used in cooking and risk of metabolic syndrome among Asian Indians.  

Science.gov (United States)

There is little data on the type of vegetable oil used and the prevalence of metabolic syndrome (MS) in Asian Indians. Food frequency questionnaire was used to document the type of cooking oil in 1875 adults in Chennai city. MS was assessed by new harmonizing criteria. The prevalence of MS was higher among sunflower oil users (30.7%) than palmolein (23.2%) and traditional oil (17.1%, p < 0.001) users. The higher prevalence of MS in sunflower oil group persisted even when stratified according to body mass index, except in obese groups. The risk of MS was further compounded by quantity of refined cereals consumed. Higher LA%E and linoleic acid/alpha-linolenic acid ratio in sunflower oil probably contributes to increased risk of MS. PMID:23025245

Lakshmipriya, Nagarajan; Gayathri, Rajagopal; Praseena, Kallingal; Vijayalakshmi, Parthasarathy; Geetha, Gunasekaran; Sudha, Vasudevan; Krishnaswamy, Kamala; Anjana, Ranjit Mohan; Henry, Jeyakumar; Mohan, Viswanathan

2013-03-01

99

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.

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

2014-01-01

100

Ecological carrying capacity of current land use assessed according to types of abiotic complexes; 1 : 500 000  

International Nuclear Information System (INIS)

The map presents ecological carrying capacity of current land use assessed according to types of abiotic complexes on the territory of the Slovak Republic. Ecological carrying capacity is the purpose-linked property of landscape, which expresses the rate of admissible (suitable) land use through anthropic activities without damaging or disturbing the natural properties, processes, and relationships between the landscape elements (abiotic, biotic, and socio-economic) and the environmental quality. Ecological limits represent the tool for assessment of ecological carrying capacity of the landscape. The rate of suitability of land use of the particular type of abiotic complex is assessed pursuing the levels of the ecological carrying capacity of landscape (CCL). Based on the comparison of the existing and the proposed use, the following was assessed: · Suitable use (1st level of CCL) - the category covers all areas where it is not necessary to change the present land use. Areas with no necessity to alter the ecological development are marked in the map. Their present use is below the threshold of ecological carrying capacity. · Moderately suitable (still sustainable) use (2nd level of CCL) - the category covers all areas where it is not necessary to change the present land use although it does not entirely respond to the landscape-ecological conditions of the territory. The areas with the possibility of conditional ecological development in some cases complemented by protective measures are marked in the map. The present use approximates the threshold of ecological carrying capacity. · Unsuitable (unsustainable) use (3rd level of CCP) - this category covers all areas where it is not possible to maintain the existing way of use either from the ecological or technological points of view. The map shows the areas with necessary changes of use accompanied by proposal of measures, as the present use exceeds ecological carrying capacity (above the threshold of ecological carrying capacity). The resulting proposal has been assessed on the basis of abiotic limits and it requires further modifications pursuing the biotic, abiotic and socio-economic limits. (authors

2002-01-01

 
 
 
 
101

Wildfires alter rodent community structure across four vegetation types in southern California, USA  

Science.gov (United States)

We surveyed burned and unburned plots across four habitat reserves in San Diego County, California, USA, in 2005 and 2006, to assess the effects of the 2003 wildfires on the community structure and relative abundance of rodent species. The reserves each contained multiple vegetation types (coastal sage scrub, chaparral, woodland, and grassland) and spanned from 250 m to 1078 m in elevation. Multivariate analyses revealed a more simplified rodent community structure in all burned habitats in comparison to unburned habitats. Reduction in shrub and tree cover was highly predictive of changes in post-fire rodent community structure in the burned coastal sage scrub and chaparral habitats. Reduction in cover was not predictive for the less substantially burned woodlands and grasslands, for which we hypothesized that interspecific competition played a greater role in post-fire community structure. Across vegetation types, generalists and open habitat specialists typically increased in relative abundance, whereas closed habitat specialists decreased. We documented significant increases in relative abundance of the deer mouse (Peromyscus maniculatus Wagner) and Dulzura kangaroo rat (Dipodomys simulans Merriam). In contrast, we found significant decreases in relative abundance for the California mouse (Peromyscus californicus Gambel), San Diego pocket mouse (Chaetodipus fallax Merriam), desert woodrat (Neotoma lepida Thomas), and brush mouse (Peromyscus boylii Baird). Currently, our research program involves assessment of whether habitat conservation plans (HCPs) in southern California provide long-term protection to HCP covered species, as well as preserve ecosystem function. The scenario of increased wildfires needs to be incorporated into this assessment. We discuss our results in relation to management and conservation planning under a future scenario of larger and more frequent wildfires in southern California.

Brehme, Cheryl S.; Clark, Denise R.; Rochester, Carlton J.; Fisher, Robert N.

2011-01-01

102

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

103

High abundance of dioecious plants in a tropical coastal vegetation.  

Science.gov (United States)

We examined the frequency of hermaphroditic, monoecious, and dioecious species of angiosperms in restinga (sandy coastal plain) vegetation in SE Brazil. The study site was a vegetation mosaic comprising nine plant formations, ranging from open types to forest. Dioecy (14% of 566 species) was similar to other tropical vegetations and strongly associated with woodiness and entomophily. However, more interestingly, there was an exceptionally high percentage (35%) of dioecious species among the dominant woody plants. This pattern has not been previously reported, and we discuss the extent to which it is ecologically driven. We argue that the high abundance of dioecious plants in this resource-poor environment can be attributed to ecological traits related to long-distance dispersal, ecological vigor, and possibly, vegetative reproduction. PMID:21646169

Matallana, Gloria; Wendt, Tânia; Araujo, Dorothy S D; Scarano, Fábio R

2005-09-01

104

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

105

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 managed chestnut forest and an intensively managed bamboo forest in subtropical China. The SOC in the 0–20 and 20–40 cm soil layers was the highest in the bamboo forest (31.6–34.8 g·C·kg?1, followed by the evergreen broad-leaf forest (10.2–19.9 g·C·kg?1, the pine forest (8.5–13.6 g·C·kg?1 and the chestnut forest (6.3–12.2 g·C·kg?1. The SOC was largely in the coarse fraction under the evergreen broad-leaf, pine and bamboo forests, while it was largely in the fine fraction in the chestnut forest, suggesting that SOC in the chestnut forest was likely more stable than that in the other forest vegetation-land use types. The SOC in the light fraction under the four forest vegetation-land use types ranged from 1.4 to 13.1 g·C·kg?1 soil, representing 21%–37% of the total organic C; this suggests that the majority of the SOC was in the better protected, heavy fraction. We conclude that forest vegetation-land use type (and the associated management practices influenced SOC distribution in particle size and density fractions in the studied subtropical forests in southeastern China.

Suyun Shang

2014-06-01

106

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

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 cycle including chemical weathering at the global scale. We use simulation experiments to assess the relative importance of the different uptake mechanisms to alleviate P limitation on biomass production. Implementing P limitation on biomass synthesis allows the assessment of the efficiencies of biomass production across different ecosystems. We find that active P-uptake is an essential mechanism for sustaining P availability on long time scales, whereas biotic de-occlusion might serve as a buffer on time scales 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 modeling 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 older soils becomes P-limited leading to a smaller biomass production efficiency. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and ecological time scales under different environmental settings.

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

2013-12-01

107

Seasonal variations in the biomass, quantity and quality of agar, from the reproductive and vegetative stages of Gracilaria (verrucosa type)  

Energy Technology Data Exchange (ETDEWEB)

Optimum growth of Gracilaria (verrucosa type) in British Columbia occurred between 5 and 6 meters below mean field level and correlated with solar radiation throughout the season. Vegetative populations declined with a consequent increase in reproductive forms to a maximum in July. Tetrasporophytes dominated the reproductive population and in July attained the greatest seasonal biomass of all forms of the alga. Maximum population and biomass were attained by carposporophytes in July and by male gametophytes one month earlier. An inverse relationship between biomass and yield of agar was apparent only for the vegetative and tetrasporic forms of the alga. Variations in yields, gel strengths, and gelation characteristics of the agars isolated, were demonstrated to be dependent on time of season and life stages of the alga. Ranked in the following decreasing order of merit as a source of agar were the cystocarpic, tetrasporic, vegetative and male gametophytic forms of Gracilaria (verrucosa type).

Whyte, J.N.C.; Englar, J.R.; Saunders, R.G.; Lindsay, J.C.

1981-09-01

108

Evaluating the Usefulness of High-Temporal Resolution Vegetation Indices to Identify Crop Types  

Science.gov (United States)

The National Aeronautical and Space Agency (NASA) and the United States Department of Agriculture (USDA) jointly sponsored research covering the 2004 to 2006 South American crop seasons that focused on developing methods for the USDA's Foreign Agricultural Service's (FAS) Production Estimates and Crop Assessment Division (PECAD) to identify crop types using MODIS-derived, hyper-temporal Normalized Difference Vegetation Index (NDVI) images. NDVI images were composited in 8 day intervals from daily NDVI images and aggregated to create a hyper-termporal NDVI layerstack. This NDVI layerstack was used as input to image classification algorithms. Research results indicated that creating high-temporal resolution Normalized Difference Vegetation Index (NDVI) composites from NASA's MODerate Resolution Imaging Spectroradiometer (MODIS) data products provides useful input to crop type classifications as well as potential useful input for regional crop productivity modeling efforts. A current NASA-sponsored Rapid Prototyping Capability (RPC) experiment will assess the utility of simulated future Visible Infrared Imager / Radiometer Suite (VIIRS) imagery for conducting NDVI-derived land cover and specific crop type classifications. In the experiment, methods will be considered to refine current MODIS data streams, reduce the noise content of the MODIS, and utilize the MODIS data as an input to the VIIRS simulation process. The effort also is being conducted in concert with an ISS project that will further evaluate, verify and validate the usefulness of specific data products to provide remote sensing-derived input for the Sinclair Model a semi-mechanistic model for estimating crop yield. The study area encompasses a large portion of the Pampas region of Argentina--a major world producer of crops such as corn, soybeans, and wheat which makes it a competitor to the US. ITD partnered with researchers at the Center for Surveying Agricultural and Natural Resources (CREAN) of the National University of Cordoba, Argentina, and CREAN personnel collected and continue to collect field-level, GIS-based in situ information. Current efforts involve both developing and optimizing software tools for the necessary data processing. The software includes the Time Series Product Tool (TSPT), Leica's ERDAS Imagine, and Mississippi State University's Temporal Map Algebra computational tools.

Hilbert, K.; Lewis, D.; O'Hara, C. G.

2006-12-01

109

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

Directory of Open Access Journals (Sweden)

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

110

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

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Full Text Available 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.

A. P. Palacz

2013-05-01

111

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

112

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

Directory of Open Access Journals (Sweden)

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

113

Vegetative characteristics of five forest types across a lake states sulfate deposition gradient. Forest Service resource bulletin  

Energy Technology Data Exchange (ETDEWEB)

The report presents the vegetative characteristics of the five forest types that comprised the study plots established to test the hypothesis that the wet sulfate deposition gradient across the Lake States is reflected in the amount of accumulated sulfur in soil and tree tissue, which in turn is reflected in tree growth.

Ohmann, L.F.; Grigal, D.F.; Shifley, S.R.; Berguson, W.E.

1994-04-20

114

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  

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, ...

MARILUZA GRANJA BARROS

2001-01-01

115

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2005-01-01

116

Short-term trends in vegetation cover of Danish semi-natural ecosystems : a landscape-ecological assessment of main drivers indicated by traits of winner and loser species  

DEFF Research Database (Denmark)

The landscapes in which many plant communities persist today are increasingly modified by anthropogenic activities, especially in Denmark, where most communities are influenced by for example atmospheric deposition of Nitrogen, changes in soil moisture levels (e.g. ground water-table changes caused by drainage) and changes in management regimes (primarily reduced grazing-pressure). Such modifications of the environment are filtering the persistence of species into those that are adapted to these new conditions (winners) and those that are not (losers). Across the landscape, it is reasonable to expect species with similar traits to respond similarly to systematic shifts in habitat conditions and disturbance. Consequently, contrasting traits of winner and loser species could be a powerful tool in identifying mechanisms that might be driving community changes. In this study, we use a large dataset of vegetation surveys from 207 semi-natural non-forested sites in Denmark, identifying temporal short-term changes in vegetation cover, notably identifying those species that are winners and losers. A further goal is to identify environmental drivers of contemporary vegetation change in Danish semi-natural habitats by quantifying which functional traits makes species decline or increase. We therefore assess whether winners and losers differ with regard to key functional traits and ecological indicator values, and whether these results match our expectations given the current anthropogenic disturbance regime. Notably, do winner and loser species display distinct sets of traits of the ones related to: exotic species invasion, eutrophication by nitrogen deposition, management changes (decreasing grazing and associated encroachment by woody plants), soil moisture changes (due to excessive water extraction and drainage)? Preliminary results suggest that even during a relative short time span of just seven years, it is possible to identify winner and loser species, indicating that significant shifts in species compositionare currently taking place in Danish semi-natural ecosystems. The number of identified loser species was greater than the number of identified winner species, suggesting that homogenization of species composition across the landscape may be a concern. Today, management of semi-natural habitats is a common conservation measure. However, despite traditional management, habitats may still be vulnerable to compositional changes due to e.g. surrounding land-use and atmospheric nitrogen deposition. The preliminary results from this study, are dichotomous in that it seems some factors as for example soil moisture and woody species encroachment are being managed in a way that opposites expectations from human disturbances, whereas management can not combat the effects of nitrogen deposition. Further analyses are still being developed to differentiate the landscape pattern of winners and losers into the specific habitat-types to induce differences between them in their responses to environmental drivers.

Timmermann, Allan; Damgaard, Christian

117

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

Energy Technology Data Exchange (ETDEWEB)

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

118

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

International Nuclear Information System (INIS)

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-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.

2011-03-18

119

Seasat synthetic aperture radar ( SAR) response to lowland vegetation types in eastern Maryland and Virginia.  

Science.gov (United States)

Examination of Seasat SAR images of eastern Maryland and Virginia reveals botanical distinctions between vegetated lowland areas and adjacent upland areas. Radar returns from the lowland areas can be either brighter or darker than returns from the upland forests. Scattering models and scatterometer measurements predict an increase of 6 dB in backscatter from vegetation over standing water. This agrees with the 30-digital number (DN) increase observed in the digital Seasat data. The density, morphology, and relative geometry of the lowland vegetation with respect to standing water can all affect the strength of the return L band signal.-from Authors

Krohn, M. D.; Milton, N. M.; Segal, D. B.

1983-01-01

120

Radio-capacity of different types of natural ecosystems (without man) and their ecological standardization principles  

International Nuclear Information System (INIS)

In this article the theory of radio-capacity of natural ecosystems (excluding mankind) is applied to the definition of ecological standards for permissible releases in the environment. A specific limit of radionuclide contamination of wild life which can be considered as the basis of an ecological standardization (64-640 kb kg-1) is proposed. BAsic equations for evaluation of maximum permissible releases into a lake ecosystem are presented. Ecological standards for benthos are 10 to 100 times less than the ecological standards for inhabitants of the water column. It is shown that the existing levels of radionuclide contamination of terrestrial slope ecosystems in the 30-km zone around Chernobyl Nuclear Power Plant (NPP) exceed the proposed ecological standards. (authors)

1997-01-01

 
 
 
 
121

Vegetation NDVI Linked to Temperature and Precipitation in the Upper Catchments of Yellow River  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation in the upper catchment of Yellow River is critical for the ecological stability of the whole watershed. The dominant vegetation cover types in this region are grassland and forest, which can strongly influence the eco-environmental status of the whole watershed. The normalized difference vegetation index (NDVI) for grassland and forest has been calculated and its daily correlation models were deduced by Moderate Resolution Imaging Spectroradiometer products on 12 dates in 2000, 200...

Hao, F.; Zhang, X.; Ouyang, W.; Skidmore, A. K.; Toxopeus, A. G.

2012-01-01

122

The hydrological responses of different land cover types in a re-vegetation catchment area of the Loess Plateau, China  

Directory of Open Access Journals (Sweden)

Full Text Available The impact of re-vegetation on soil moisture dynamics was investigated by comparing five land cover types. Soil moisture and temperature variations under grass (Andropogon, subshrub (Artemisia scoparia, shrub (Spiraea pubescens, tree (Robinia pseudoacacia, and crop (Zea mays vegetation were monitored in an experiment performed during the growing season of 2011. There were more than 10 soil moisture pulses during the period of data collection, and the surface soil moisture of all of the land cover types showed an increasing trend. Corn cover was associated with consistently higher soil moisture readings than the other surfaces. Grass and subshrubs showed an intermediate moisture level, with that of grass being slightly higher than that of subshrub most of the time. Shrubs and trees were characterized by lower soil moisture readings, with the shrub levels consistently being slightly higher than those of the trees. With the exception of the corn land cover type, the average soil temperature showed the same regime as the average moisture content, but exhibiting a downward trend throughout the observation period. Three typical decreasing periods were chosen to compare the differences in water losses. In periods of both relatively lower and higher water soil moisture contents, subshrubs lost the largest amount of water. The daily water loss associated with corn was most variable. The tree and shrub sites presented an intermediate level, with that of tree being slightly higher compared to shrub; the daily water loss trends of these two land cover types were similar and were more stable than those of the other types. The amount of water loss related to the grass land cover type is determined by the initial moisture content. Soil under subshrubs acquired and retained soil moisture resources more efficiently than the other cover types, representing an adaptive vegetation type in this area.

S. Wang

2012-05-01

123

The hydrological responses of different land cover types in a re-vegetation catchment area of the Loess Plateau, China  

Science.gov (United States)

The impact of re-vegetation on soil moisture dynamics was investigated by comparing five land cover types. Soil moisture and temperature variations under grass (Andropogon), subshrub (Artemisia scoparia), shrub (Spiraea pubescens), tree (Robinia pseudoacacia), and crop (Zea mays) vegetation were monitored in an experiment performed during the growing season of 2011. There were more than 10 soil moisture pulses during the period of data collection, and the surface soil moisture of all of the land cover types showed an increasing trend. Corn cover was associated with consistently higher soil moisture readings than the other surfaces. Grass and subshrubs showed an intermediate moisture level, with that of grass being slightly higher than that of subshrub most of the time. Shrubs and trees were characterized by lower soil moisture readings, with the shrub levels consistently being slightly higher than those of the trees. With the exception of the corn land cover type, the average soil temperature showed the same regime as the average moisture content, but exhibiting a downward trend throughout the observation period. Three typical decreasing periods were chosen to compare the differences in water losses. In periods of both relatively lower and higher water soil moisture contents, subshrubs lost the largest amount of water. The daily water loss associated with corn was most variable. The tree and shrub sites presented an intermediate level, with that of tree being slightly higher compared to shrub; the daily water loss trends of these two land cover types were similar and were more stable than those of the other types. The amount of water loss related to the grass land cover type is determined by the initial moisture content. Soil under subshrubs acquired and retained soil moisture resources more efficiently than the other cover types, representing an adaptive vegetation type in this area.

Wang, S.; Fu, B. J.; Gao, G. Y.; Zhou, J.

2012-05-01

124

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

Directory of Open Access Journals (Sweden)

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

125

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.

2012-01-01

126

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

2014-04-01

127

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

128

Response of normalized difference vegetation index in main vegetation types to climate change and their variations in different time scales along a North-South Transect of Eastern China  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Aims Climate change characterized by global warming has posed a great threat to terrestrial ecosystems and sustainable development of human society. Our objective was to examine the response of major vegetation types to climate change.Methods We used the biweekly dataset of the National Oceanographic and Atmospheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) normalized difference vegetation index (NDVI) and climatic data from 752 standard stations in China for 1982?...

2011-01-01

129

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Daniel Paredes; Luis Cayuela; Gurr, Geoff M.; Mercedes Campos

2013-01-01

130

The Uptake of Heavy Metals by Fruit Type Vegetables Grown in Selected Agricultural Areas  

Directory of Open Access Journals (Sweden)

Full Text Available A study on the uptake of heavy metals by fruit vegetables from agricultural areas was conducted at Agrotek, Sepang and Bangi, Selangor. The objective of the study was to determine the uptake of heavy metals by chilies (Capsicum annum and long beans (Vigna sinensis from the soil. Heavy metals studied were Pb, Cd and Zn. Wet digestion method was used for heavy metals analysis in the vegetables. Heavy metals from soil samples were extracted by sequential extraction method, which extract heavy metals from easily and freely leachable fraction (EFLE, acid reduction (AR, organic oxidation (OO and resistant fraction (RR. The results of the study showed that the level of Zn content in long beans (Vigna sinensis was higher than in chilies (Capsicum annum. However the concentrations of heavy metals studied in these vegetables were still below the maximum level allowed by the Malaysian Food Act (1983 and Food Regulations (1985 for Pb (2.00 mg kg-1, Cd (1.00 mg kg-1 and Zn (30.00 mg kg-1.

J. Khairiah

2004-01-01

131

Variations in fresh fruit and vegetable quality by store type, urban-rural setting and neighbourhood deprivation in Scotland. — Measures of the Food Environment  

Science.gov (United States)

Cummins S, Smith DM, Taylor M, Dawson J, Marshall D, Sparks L, Anderson AS. Variations in fresh fruit and vegetable quality by store type, urban-rural setting and neighbourhood deprivation in Scotland.

132

Structural and floristic changes caused by gamma radiation in understory vegetation of two forest types in northern Wisconsin  

International Nuclear Information System (INIS)

Structural and floristic changes of the understory vegetation of gamma-irradiated aspen and maple-aspen-birch (MAB) communities in northern Wisconsin were quantified by comparing the pre- and postirradiation floristic composition and vegetational cover. A size-dependent radiosensitivity was determined among three vegetational strata, the tall shrubs being the most sensitive, low shrubs intermediate, and herbs the most resistant. Corylus cornuta, whose nuclear characteristics indicated that it could be resistant, was very sensitive and was completely eliminated at exposures of 500 r/20-hr day or higher. The cover of Rubus strigosus, minimal before irradiation, increased manifold and accounted for most of the shrub cover 2 years after the conclusion of irradiation. Among herbs, Carex pensylvanica and Luzula acuminata were very resistant, and Trillium grandiflorum, Aralia nudicaulis, Oryzopsis asperifolia, and Clintonia borealis were very sensitive. The herbaceous stratum of the aspen type appeared more resistant than that of the MAB. This difference apparently resulted from differences in floristic composition of the two communities

1977-01-01

133

Effects of soil type and genotype on lead concentration in rootstalk vegetables and the selection of cultivars for food safety.  

Science.gov (United States)

Lead (Pb) contamination of soil poses severe health risks to humans through vegetable consumption. The variations of Pb concentration in different parts of rootstalk vegetables (radish, carrot and potato) were investigated by using twelve cultivars grown in acidic Ferralsols and neutral Cambisols under two Pb treatments (125 mg kg(-1) and 250 mg kg(-1) for Ferralsols; 150 mg kg(-1) and 300 mg kg(-1) for Cambisols) in a pot experiment. The Pb concentration in edible parts was higher in Ferralsols under two Pb treatments, with range from 0.28 to 4.14, 0.42-10.66 mg kg(-1) (fresh weight) respectively, and all of them exceeded the food safety standard (0.1 mg kg(-1)) recommended by the Codex Alimentarius Commission of FAO and WHO. The Pb concentration in edible parts was significantly affected by genotype, soil type and the interaction between these two factors. The variation of Pb concentration in different cultivars was partially governed by Pb absorption and the transfer of Pb from aerial to edible part. The results revealed that caution should be paid to the cultivation of rootstalk vegetables in Pb-contaminated Ferralsols without any agronomic management to reduce Pb availability and plant uptake. For Cambisols with slight to moderate Pb contamination, growing potato cultivar Shandong No.1 and Chongqing No.1 was effective in reducing the risk of Pb entering human food chain. The results suggest the possibility of developing cultivar- and soil-specific planting and monitoring guidelines for the cultivation of rootstalk vegetables on slight to moderate Pb-contaminated soils. PMID:23542226

Ding, Changfeng; Zhang, Taolin; Wang, Xingxiang; Zhou, Fen; Yang, Yiru; Yin, Yunlong

2013-06-15

134

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

135

Influência do tipo da cobertura vegetal sobre a erosão no semi-árido Paraibano Influence of the type of vegetal cover on sediment yield in the semiarid of Paraíba state  

Directory of Open Access Journals (Sweden)

Full Text Available O tipo de cobertura vegetal, presente numa área, tem grande influência sobre o escoamento superficial e a produção de sedimentos. O objetivo do presente trabalho é estabelecer uma relação entre o tipo da cobertura vegetal e a erosão do solo nu, mediante uma equação empírica da perda de solo. A equação proposta foi calibrada usando-se dados sintéticos gerados por um modelo físico hidrossedimentológico, cujos parâmetros de erosão foram determinados como valores representativos de uma área desmatada do semi-árido paraibano. Apresenta-se uma comparação entre os valores calculados pela equação e os dados observados em várias parcelas de erosão, as quais apresentavam condições de cobertura vegetal e declividade distintas, localizadas na Bacia Experimental de Sumé, PB. Esta comparação permitiu uma avaliação da influência do tipo de cobertura vegetal sobre a erosão do solo.The type of vegetation cover present in an area, greatly influences the surface runoff as well as the sediment yield. The objective of this paper is to establish a relationship between the type of vegetal cover and erosion by means of an empirical equation for soil loss. The proposed equation was calibrated using synthetic data obtained from a physically-based runoff-erosion model in which the erosion parameter values are representative of a cleared bare-land surface in the semiarid area of Paraíba State. A comparison between the values obtained from the equation and the observed data collected from several erosion plots in the Sumé Experimental Watershed with different conditions of vegetal cover and slope is presented as an evaluation of the influence of the vegetation cover on soil erosion.

Celso Augusto Guimarães Santos

2000-04-01

136

Forecasts of future terrain and vegetation types at Olkiluoto and implications for spatial and temporal aspects of biosphere modelling.  

Science.gov (United States)

In Finland, a nuclear repository site is situated on the western coast where the current land uplift rate is 6mm/yr. A set of tools has been developed for predicting the future terrain and vegetation types, and for producing estimates of the site-specific parameter values for use in simplified radionuclide transport models. Although the landscape will change considerably within the next millennia, the likely changes are relatively predictable. By comparing the results to the site data, the effect of human activities can be at least partially quantified. PMID:18515124

Ikonen, A T K; Aro, L; Leppänen, V

2008-11-01

137

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Cooper, A. J.; Forouhi, N. G.; Ye, Z.; Buijsse, B.; Feskens, E. J. M.

2012-01-01

138

Ecological Transcriptomics of Lake-Type and Riverine Sockeye Salmon (Oncorhynchus nerka)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background: There are a growing number of genomes sequenced with tentative functions assigned to a largeproportion of the individual genes. Model organisms in laboratory settings form the basis for the assignment ofgene function, and the ecological context of gene function is lacking. This work addresses this shortcoming byinvestigating expressed genes of sockeye salmon (Oncorhynchus nerka) muscle tissue. We compared morphologyand gene expression in natural juvenile sockeye populations relate...

Pavey, Scott; Sutherland, Ben; Leong, Jong; Robb, Adrienne

2011-01-01

139

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.

140

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.

 
 
 
 
141

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  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2009-01-01

142

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 Ã? 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

143

Evaluation of sensor types and environmental controls on mapping biomass of coastal marsh emergent vegetation  

Science.gov (United States)

There is a need to quantify large-scale plant productivity in coastal marshes to understand marsh resilience to sea level rise, to help define eligibility for carbon offset credits, and to monitor impacts from land use, eutrophication and contamination. Remote monitoring of aboveground biomass of emergent wetland vegetation will help address this need. Differences in sensor spatial resolution, bandwidth, temporal frequency and cost constrain the accuracy of biomass maps produced for management applications. In addition the use of vegetation indices to map biomass may not be effective in wetlands due to confounding effects of water inundation on spectral reflectance. To address these challenges, we used partial least squares regression to select optimal spectral features in situ and with satellite reflectance data to develop predictive models of aboveground biomass for common emergent freshwater marsh species, Typha spp. and Schoenoplectus acutus, at two restored marshes in the Sacramento–San Joaquin River Delta, California, USA. We used field spectrometer data to test model errors associated with hyperspectral narrowbands and multispectral broadbands, the influence of water inundation on prediction accuracy, and the ability to develop species specific models. We used Hyperion data, Digital Globe World View-2 (WV-2) data, and Landsat 7 data to scale up the best statistical models of biomass. Field spectrometer-based models of the full dataset showed that narrowband reflectance data predicted biomass somewhat, though not significantly better than broadband reflectance data [R2 = 0.46 and percent normalized RMSE (%RMSE) = 16% for narrowband models]. However hyperspectral first derivative reflectance spectra best predicted biomass for plots where water levels were less than 15 cm (R2 = 0.69, %RMSE = 12.6%). In species-specific models, error rates differed by species (Typha spp.: %RMSE = 18.5%; S. acutus: %RMSE = 24.9%), likely due to the more vertical structure and deeper water habitat of S. acutus. The Landsat 7 dataset (7 images) predicted biomass slightly better than the WV-2 dataset (6 images) (R2 = 0.56, %RMSE = 20.9%, compared to R2 = 0.45, RMSE = 21.5%). The Hyperion dataset (one image) was least successful in predicting biomass (R2 = 0.27, %RMSE = 33.5%). Shortwave infrared bands on 30 m-resolution Hyperion and Landsat 7 sensors aided biomass estimation; however managers need to weigh tradeoffs between cost, additional spectral information, and high spatial resolution that will identify variability in small, fragmented marshes common to the Sacramento–San Joaquin River Delta and elsewhere in the Western U.S.

Byrd, Kristin B.; O'Connell, Jessica L.; Di Tommaso, Stefania; Kelly, Maggi

2014-01-01

144

Terrestrial ecology  

International Nuclear Information System (INIS)

The main effort of the Terrestrial Ecology Division has been redirected to a comprehensive study of the Espiritu Santo Drainage Basin located in northeastern Puerto Rico. The general objective are to provide baseline ecological data for future environmental assessment studies at the local and regional levels, and to provide through an ecosystem approach data for the development of management alternatives for the wise utilization of energy, water, and land resources. The interrelationships among climate, vegetation, soils, and man, and their combined influence upon the hydrologic cycle will be described and evaluated. Environmental management involves planning and decision making, and both require an adequate data base. At present, little is known about the interworkings of a complete, integrated system such as a drainage basin. A literature survey of the main research areas confirmed that, although many individual ecologically oriented studies have been carried out in a tropical environment, few if any provide the data base required for environmental management. In view of rapidly changing socio-economic conditions and natural resources limitations, management urgently requires data from these systems: physical (climatological), biological, and cultural. This integrated drainage basin study has been designed to provide such data. The scope of this program covers the hydrologic cycle as it is affected by the interactions of the physical, biological, and cultural systems

1977-10-01

145

Characterization of glycosyltransferase activity of wild-type Leuconostoc mesenteroides strains from Bulgarian fermented vegetables.  

Science.gov (United States)

Glycosyltransferase activity of 13 Leuconostoc mesenteroides strains isolated from Bulgarian fermented vegetables was investigated. All the strains displayed a mucoid phenotype on sucrose-containing agar media. Strains were characterized according to carbohydrate fermentation, species-specific multiple PCR using several primers, repetitive element-PCR fingerprinting using (GTG)(5) primers and glycosyltransferase activity. Level of activity and cellular localization (soluble or cell-associated) were variable among strains. Precipitation of exopolysaccharides produced from sucrose by the soluble fractions from these strains allowed recovery of only glucans and further characterization by (1)H and (13)C NMR analysis and enzymatic digestion with dextranase revealed dextran production. However, levans could be detected in presence of raffinose as fructosyl donor. Both fructosyltransferase and glucosyltransferase encoding genes were detected by PCR and both active enzymes were detected after functional characterization by SDS-PAGE electrophoresis and in situ polymer production after incubation with sucrose. This work therefore showed that concomitant production of glucosyltransferase and fructosyltransferase is widespread in L. mesenteroides strains. PMID:22932848

Vasileva, Tonka; Iliev, Ilia; Amari, Myriam; Bivolarski, Veselin; Bounaix, Marie-Sophie; Robert, Hervé; Morel, Sandrine; Rabier, Philippe; Ivanova, Iskra; Gabriel, Bruno; Fontagné-Faucher, Catherine; Gabriel, Valérie

2012-10-01

146

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

147

Analysis of the riparian vegetation (Ia land type of the proposed Vhembe-Dongola National Park, Limpopo Province, South Africa  

Directory of Open Access Journals (Sweden)

Full Text Available The establishment of the Vhembe-Dongola National Park has been an objective of several conservationists for many years. The ultimate objective is that this park would become a major component of a transfrontier 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 Ia land type of the proposed area for the park. Sampling was done by means of the Braun-Blanquet method. A total of 70 stratified random relevés were sampled in the Ia land type. All relevé data was imported into the database TURBOVEG 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. From the phytosociological table four plant communities were identified and described in the Ia land type. The ordination algorithm, DECORANA, was applied to the floristic data in order to illustrate floristic relationships between plant communities, to detect possible gradients in and between communities and to detect possible habitat gradients and/or disturbance gradients associated with vegetation gradients.

K. Kellner

2003-12-01

148

Variation in Protein Content and Amino Acids in the Leaves of Grain, Vegetable and Weedy Types of Amaranths  

Directory of Open Access Journals (Sweden)

Full Text Available Malnutrition has affected almost 31% of pre-school children. This paper provides the information of nutritional values (leaf protein, 15 amino acids, biomass and leaf dry matter of grain, vegetable and weedy types of amaranths (n = 76 accessions; particularly those novel materials originated from the highland areas of Sumatra-Takengon. The highest values of leaf protein and total amino acids were found in many weedy species (A. viridis, A. blitum L. and A. dubius. The ranges of leaf protein and total amino acids in most of weedy types were 12–29 g 100 g?1 DM and 84–93 g 100 g?1 DW protein, respectively. The leaves of amaranths were found to be a good source for lysine which is the limiting essential amino acids in most of cereal plants. Their values were in the range of 6 g 100 g?1 DW protein which are close to that of good protein quality according to FAO/WHO’s standard. The leaves of underutilized weedy species of A. dubius, A. blitum, A. viridis and the dual purpose types of A. caudatus L., A. cruentus L. deserve to be further exploited as a low cost solution for solving malnutrition problems, especially in Indonesia.

Ryo Ohsawa

2013-05-01

149

Calcareous nannofossils from the Nkalagu formation type locality (middle Turonian to Coniacian, southern Nigeria): biostratigraphy and palæo-ecologic implications  

Science.gov (United States)

The calcareous nannofossil assemblages of the Nkalagu Formation have been investigated at its type locality, concerning their biostratigraphic and palæo-ecological applicability. Two calcareous nannofossil zones can be distinguished in the Nkalagu quarry sections: the Eiffellithus eximius zone (Middle Turonian to early Late Turonian) and the Marthasterites furcatus zone (Late Turonian to Coniacian). The first appearance of Marthasterites furcatus indicates the lower boundary of the Marthasterites furcatus zone. This boundary is within the Late Turonian, as shown by the first appearance of the index species long before the first appearance of Coniacian planktonic foraminifera and the co-occurrence with Late Turonian inoceramids. The dominating species Watznaueria barnesae points to oceanic environments at Nkalagu for the Middle Turonian to Coniacian interval.

Gebhardt, H.

2001-04-01

150

An ecological study of the major vegetation communities of the Vaalbos National Park, Northern Cape. 1. The Than-Droogeveld section  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A detailed classification, description and mapping of the Than-Droogeveld section of the Vaalbos National Park, Northern Cape Province, were initiated. This classification is intended to serve as an ecological basis for the establishment of an efficient wildlife management programme as well as conservation policies for the Vaalbos National Park. Using a numerical classification technique (TWINSPAN) as a first approximation, the classification was refined by applying Braun-Blanquet procedures....

Bezuidenhout, H.

1994-01-01

151

[Effects of arbuscular mycorrhizal fungi on the vegetation restoration of different types of coal mine spoil banks].  

Science.gov (United States)

A greenhouse pot experiment was conducted to investigate the influence of arbuscular mycorrhizal (AM) fungi Glomus etunicatum (GE) and Glomus versiforme (GV) on the plant growth, nutrient uptake, C: N: P stoichiometric, uptake of heavy metals by maize (Zea mays L.) grown in three types of coal mine spoil banks. The aim was to provide a technical basis for the revegetation of coal mine spoil banks in grassland ecosystem. The results indicated that the symbiotic associations were successfully established between two isolates and maize grown in the three substrates, with an average mycorrhizal colonization rate ranging from 36% to 54%. The colonization of two AM fungi significantly increased the dry weight of maize grown in recent discharged and weathered coal mine spoils and GE increased those grown in weathered coal mine spoil. Inoculation with AM fungi promoted the uptake of N, P and K by maize to varying degrees. In addition, inoculation with GE and GV also decreased C: N: P ratios, supporting the growth rate hypothesis, and had significantly differences on concentrations of Cu, Fe, Mn and Zn in shoots and roots of maize. The results indicated that GE and GV had different mycorrhizal effects on maize in the three types of substrates. GV was more suitable for the revegetation of recent discharged coal mine spoil and weathered coal mine spoil, while GE was more suitable for the revegetation of spontaneous combusted coal mine spoil. The experiment demonstrates that AM fungi have a potential role for maize to enhance the ability to adapt the composite adversity of different types of coal mine spoil and play a positive role in the revegetation of different coal mine spoil banks. Further field experiments should be conducted to evaluate the practical effects of AM fungi on the vegetation restoration of different types of coal mine spoil under field conditions. PMID:24455958

Zhao, Ren-Xin; Guo, Wei; Fu, Rui-Ying; Zhao, Wen-Jing; Guo, Jiang-Yuan; Bi, Na; Zhang, Jun

2013-11-01

152

Vegetation of Upper Coastal Plain depression wetlands: Environmental templates and wetland dynamics within a landscape framework.  

Energy Technology Data Exchange (ETDEWEB)

Reference wetlands play an important role in efforts to protect wetlands and assess wetland condition. Because wetland vegetation integrates the influence of many ecological factors, a useful reference system would identify natural vegetation types and include models relating vegetation to important regional geomorphic, hydrologic, and geochemical properties. Across the U.S. Atlantic Coastal Plain, depression wetlands are a major hydrogeomorphic class with diverse characteristics. For 57 functional depression wetlands in the Upper Coastal Plain of South Carolina, we characterized the principal vegetation types and used a landscape framework to assess how local (wetland-level) factors and regional landscape settings potentially influence vegetation composition and dynamics. Wetland sites were stratified across three Upper Coastal Plain landscape settings that differ in soils, surface geology, topography, and land use. We sampled plant composition, measured relevant local variables, and analyzed historical transitions in vegetative cover types. Cluster analysis identified six vegetation types, ranging from open-water ponds and emergent marshes to closed forests. Significant vegetation-environment relationships suggested environmental ''templates'' for plant community development. Of all local factors examined, wetland hydrologic regime was most strongly correlated with vegetation type, but depression size, soil textural type, and disturbance history were also significant. Because hydrogeologic settings influence wetland features, local factors important to vegetation were partly predictable from landscape setting, and thus wetland types were distributed non-randomly across landscape settings. Analysis of long-term vegetation change indicated relative stability in some wetlands and succession in others. We developed a landscape-contingent model for vegetation dynamics, with hydroperiod and fire as major driving variables. The wetland classification, environmental templates, and dynamics model provide a reference framework to guide conservation priorities and suggest possible outcomes of restoration or management.

De Steven, Diane; Toner, Maureen, M.

2004-03-01

153

Real vegetation - southern part of the Vychodoslovenska nizina Lowland  

International Nuclear Information System (INIS)

The Vychodoslovenska nizina Lowland is one of the first territories where the real vegetation was mapped on the whole area at scale 1 : 25 000. The mapped units (43) were prepared relying on the accessible knowledge of vegetation of this territory, the proper research and aerial images. They were selected in a manner allowing for reflection of site conditions and human impact on vegetation. They are mostly at the level of vegetation associations (a complex of associations). The mapped units possess their physiognomy and groups of indicating species. The aim of mapping was not the syntaxonomic characteristics of vegetation, but the properties of sites reflected by the vegetation: the water soil regime, properties of soil and substratum and the way of use by man. This source material became part of the analyses, syntheses, interpretations, and proposals used in preparation of the Ecological optimisation of use of the Vychodoslovenska nizina Lowland by the LANDEP Methodology in 1986. The fragment represents a territory where the limiting factors of distribution of certain vegetation types are: the non calcareous sand and sand dunes with xerophilous grass, locust forests and vineyards, dead river arms and inter-dune depressions with water and swamp vegetation. Heavy clayey soils with extreme water regime represent the site of flooded and withering semi-natural meadows rich in species, and pastures. The mesophile meadows and pastures are on tillable (often meliorated) soils. They are intensively used, often sowed and of little significance from the point of view of biodiversity. (author)

2002-01-01

154

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

155

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. 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

2003-01-01

156

Mapping Congo Basin vegetation types from 300 m and 1 km multi-sensor time series for carbon stocks and forest areas estimation  

Directory of Open Access Journals (Sweden)

Full Text Available This study aims to contribute to the understanding of the Congo Basin forests by delivering a detailed map of vegetation types with an improved spatial discrimination and coherence for the whole Congo Basin region. A total of 20 land cover classes were described with the standardized Land Cover Classification System (LCCS developed by the FAO. Based on a semi-automatic processing chain, the Congo Basin vegetation types map was produced by combining 19 months of observations from the Envisat MERIS full resolution products (300 m and 8 yr of daily SPOT VEGETATION (VGT reflectances (1 km. Four zones (north, south and two central were delineated and processed separately according to their seasonal and cloud cover specificities. The discrimination between different vegetation types (e.g. forest and savannas was significantly improved thanks to the MERIS sharp spatial resolution. A better discrimination was achieved in cloudy areas by taking advantage of the temporal consistency of the SPOT VGT observations. This resulted in a precise delineation of the spatial extent of the rural complex in the countries situated along the Atlantic coast. Based on this new map, more accurate estimates of the surface areas of forest types were produced for each country of the Congo Basin. Carbon stocks of the Basin were evaluated to a total of 49 360 million metric tons. The regional scale of the map was an opportunity to investigate what could be an appropriate tree cover threshold for a forest class definition in the Congo Basin countries. A 30% tree cover threshold was suggested. Furthermore, the phenology of the different vegetation types was illustrated systematically with EVI temporal profiles. This Congo Basin forest types map reached a satisfactory overall accuracy of 71.5% and even 78.9% when some classes are aggregated. The values of the Cohen's kappa coefficient, respectively 0.64 and 0.76 indicates a result significantly better than random.

A. Verhegghen

2012-12-01

157

Minimal mechanisms for vegetation patterns in semiarid regions  

CERN Multimedia

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

Martinez-Garcia, Ricardo; Hernandez-Garcia, E; Lopez, C

2014-01-01

158

Ecological half-times of 137Cs and 90Sr in dairy milk in regions with different soil types  

International Nuclear Information System (INIS)

Long-lived radionuclides 137Cs and 90Sr have been regularly monitored since the 1960's in dairy milk in Finland. The aim of this work was to study regional differences in long-term behaviour of 137Cs and 90Sr in dairy milk including the nuclear weapons tests period and the period after the Chernobyl fallout. In the milk production areas soil types vary from clayish to organic soils. Although total 137Cs deposition from nuclear weapon testings was about the same in all regions, 137Cs concentrations in dairy milk during the 1960's ranged between 5 and 35 Bq/l being highest in regions with high proportion of peat soils. The uneven deposition after the Chernobyl accident before the start of the growing season gave rise to 137Cs concentrations in dairy milk ranging from 3 Bq/l to 60 Bq/l. The ecological half-times were estimated for the decrease of 137Cs and 90Sr after the end of nuclear weapon tests period and the Chernobyl fallout for short and longer time intervals. In the milk production areas dominated by organic soils the ecological half-times for decrease of 137Cs were twice as long as in the regions with clayish soils. Half-times of 90Sr for longer time intervals were considerably longer than those for 137Cs. This long-term data on behaviour of 137Cs and 90Sr in dairy milk can be utilized in testing food chain models. The incorporation of region specific parameters in models will enhance their usefulness in case of a nuclear accident. (author)

2004-09-06

159

SOIL EMISSIONS OF N2O, NO AND CO2 IN BRAZILIAN SAVANNAS: EFFECTS OF VEGETATION TYPE, SEASONALITY, AND PRESCRIBED FIRES  

Science.gov (United States)

Using closed chamber techniques, soil fluxes of NO, N20 and C02 were measured from September 1999 through October 2000 in savanna areas in central Brazil (Cerrado) subjected to prescribed fires. Our studies focused on two vegetation types, cerrado stricto sensu (20-50% canopy cov...

160

Variation of combined heat-irradiation effects on cell inactivation in different types of vegetative bacteria  

International Nuclear Information System (INIS)

Combined effects of irradiation and heating on cell inactivation were studied with E. coli K-12 derivatives of different DNA repair capacities and some thermophilic bacteria. With E. coli K-12 mutants log-phase cells of all four strains tested were sensitized to radiation by simultaneous heating. This means that the synergistic interaction between irradiation and heating is independent of pol, uvr and rec mutation. Simultaneous heating was more effective for radiosensitization than heating before or after irradiation. This combination effect was not or only weakly observed with stationary-phase cells. From recovery experiments and sedimentation analysis of DNA from E. coli cells the process of the synergistic interaction may involve the inhibition of the recovery from heat damage and the DNA repair, especially Type II repair. In respect of thermophilic bacteria, it was found that Streptococcus thermophilus becomes more sensitive to radiation under the combined treatment with heating, while other thermophilic strains do not, according to a comparison of the radiosensitivities in terms of the D10 value of the exponential slopes of the survival curves. The latter observation with thermophilic bacteria is in contrast to E. coli. The results of sedimentation analysis of DNA of thermophiles gave unique features. (author)

1977-11-25

 
 
 
 
161

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

162

Ecological separation in foraging schedule and food type between pollinators of the California wildflower, Clarkia xantiana ssp. xantiana  

Directory of Open Access Journals (Sweden)

Full Text Available The co-occurrence of several dimensions of resource separation between coexisting consumers strengthens the hypothesis that the separation arose from and/or ameliorates interspecific competition. The two most common pollinators of the California endemic plant Clarkia xantiana ssp. xantiana (Onagraceae, the bees Hesperapis regularis (Mellitidae and Lasioglossum pullilabre (Halictidae, are known to partition flower resources by flower colour. Here we asked whether H. regularis and L. pullilabre also partition flower resources by diurnal foraging schedule and by food type (pollen versus nectar. We also quantified diurnal patterns of nectar availability, expected to be related to foraging schedules and forager responses to flower colour. The diurnal schedules of the two species differed distinctly and significantly. The majority of L. pullilabre foraging visits occurred before midday, while the majority of H. regularis visits occurred afterwards. The two species foraged for alternative food types at significantly different frequencies—nectar and pollen approximately equally frequently for H. regularis, pollen almost exclusively for L. pullilabre. Nectar standing crop declined with time of day, but it did not clearly reflect or explain previously identified colour-morph preferences. The major pollinators of C. xantiana ssp. xantiana exhibit multiple forms of ecological separation that likely reduce the intensity of competition for floral resources.

Vince Eckhart

2010-10-01

163

Spatial modelling of Bacillus anthracis ecological niche in Zimbabwe.  

Science.gov (United States)

Anthrax continues to cause significant mortalities in livestock, wildlife and humans worldwide. In Zimbabwe, anthrax outbreaks have been reported almost annually over the past four decades. In this study we tested whether anthrax outbreak data and a set of environmental variables can be used to predict the ecological niche for Bacillus anthracis using maximum entropy modelling for species geographical distribution (Maxent). Confirmed geo-referenced anthrax outbreaks data for the period 1995-2010 were used as presence locations and a set of environmental parameters; precipitation, temperature, vegetation biomass, soil type and terrain as predictor variables. Results showed that the environmental variables can adequately predict the ecological niche of B. anthracis (AUC for test data=0.717, p<0.001), with soil type as the most important predictor followed by variance of vegetation biomass and maximum temperature. These results imply that the model we tested may be used by animal health authorities in devising better control strategies for anthrax. PMID:23726015

Chikerema, S M; Murwira, A; Matope, G; Pfukenyi, D M

2013-08-01

164

THE GENESIS OF PHOTOSYNTHESIS TYPES AS THE BASIS OF ECOLOGICAL EXPANSION OF HALOPHYTIC PLANTS  

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Full Text Available The C3, C4, and CAM photosynthesis types are considerably differed by CO2 absorption intensity, its biochemistry, saturation level, water productivity, biological productivity, and other different features, which secure the plants survival at stress and extreme conditions. The aim of current research was to discover the photosynthesis peculiarities at halophytic plants species (Salicornia europaea L., Halimione pedunculata, Artemisia santonica L., Plantago lanceolata L. by salinity at model and natural conditions, and to generalize data in historical aspect. It was constituted that S. europaea L. was characterized by C3 photosynthesis passage which was switched on CAM CO2 fixation under soil salinity conditions till 4-4,5 %, but glycophyte A.santonica was immanent C4assimilation way of aspartate type.Analysis of literature data and own research allows to find out that in majority the C3photosynthesis dependence from environmental factors described by determinate curve with matched mathematical expression. It was suggested to generalize the data by Lagrange polynomial. The obtained results proved that the pattern of photosynthesis evolution is: C3 ? C4 ? CAM with commute possibilities: C3 ? CAM; C4 ? CAM.

Pyurko O.Ye.

2011-12-01

165

Food safety assessment of planting patterns of four vegetable-type crops grown in soil contaminated by electronic waste activities.  

Science.gov (United States)

A field experiment was conducted to assess the effect of crop and planting pattern on levels of cadmium (Cd), lead (Pb), and copper (Cu) in crops grown in soil contaminated by electronic waste. The crops were maize (Zea mays L. var. Shentian-1), tomato (Solanum lycopersicum L. var. Zhongshu-4), cabbage (Brassica oleracea L. var. Jingfeng-1), and pakchoi (Brassica chinensis (L.) Makino. var. Youdonger-Hangzhou). The planting patterns were crop monoculture, crop co-planted with a legume, and crop co-planted with another crop. Metal concentrations in the edible parts of the crops varied with types of metals and crops. Pb concentration was higher in leafy vegetables (cabbage and pakchoi) than in maize or tomato, Cd concentration was higher in tomato and pakchoi than in maize or cabbage, and Cu concentration was higher in maize and pakchoi than in tomato or cabbage. Metal concentrations in the edible part were also influenced by planting pattern. Relative to monoculture, co-planting and especially co-planting with Japanese clover tended to decrease Pb accumulation and increase Cd accumulation. According to the maximum permissible concentration (MPC) standard of the National Standard Agency in China, only maize (under all planting patterns) could be safely consumed. Because co-planting tended to increase Cd accumulation even in maize, however, the results suggest that maize monoculture is the optimal crop and planting pattern for this kind of contaminated soil. PMID:22054567

Liu, Ling; Hu, Liangliang; Tang, Jianjun; Li, Yuefang; Zhang, Qian; Chen, Xin

2012-01-01

166

On the Suitability of MODIS Time Series Metrics to Map Vegetation Types in Dry Savanna Ecosystems: A Case Study in the Kalahari of NE Namibia  

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Full Text Available The characterization and evaluation of the recent status of biodiversity in Southern Africa’s Savannas is a major prerequisite for suitable and sustainable land management and conservation purposes. This paper presents an integrated concept for vegetation type mapping in a dry savanna ecosystem based on local scale in-situ botanical survey data with high resolution (Landsat and coarse resolution (MODIS satellite time series. In this context, a semi-automated training database generation procedure using object-oriented image segmentation techniques is introduced. A tree-based Random Forest classifier was used for mapping vegetation type associations in the Kalahari of NE Namibia based on inter-annual intensity- and phenology-related time series metrics. The utilization of long-term inter-annual temporal metrics delivered the best classification accuracies (Kappa = 0.93 compared with classifications based on seasonal feature sets. The relationship between annual classification accuracies and bi-annual precipitation sums was conducted using data from the Tropical Rainfall Measuring Mission (TRMM. Increased error rates occurred in years with high rainfall rates compared to dry rainy seasons. The variable importance was analyzed and showed high-rank positions for features of the Enhanced Vegetation Index (EVI and the blue and middle infrared bands, indicating that soil reflectance was crucial information for an accurate spectral discrimination of Kalahari vegetation types. Time series features related to reflectance intensity obtained increased rank-positions compared to phenology-related metrics.

Stefan Dech

2009-09-01

167

Distribution and ecological consequences of ploidy variation in Artemisia sieberi in Iran  

Science.gov (United States)

Because of their high proportion in the plant kingdom polyploid taxa are considered to have had evolutionary advantages over their diploid ancestors. These advantages may have included new characteristics that enable polyploids to occupy a broader range of habitats. In this context, we assess the ecological range of Artemisia sieberi, a canopy dominant within an important vegetation type in Iran. We assess the extent to which ploidy covaries with geographical and ecological distribution and look for ecologically-significant differences in the functional characteristics of diploids and polyploids.

Jalili, Adel; Rabie, Mina; Azarnivand, Hossein; Hodgson, John G.; Arzani, Hossein; Jamzad, Ziba; Asri, Younes; Hamzehee, Behnam; Ghasemi, Farzaneh; Hesamzadeh Hejazi, S. M.; Abbas-Azimi, R.

2013-11-01

168

Renosterveld remnants – Current ecological situation and restoration perspectives  

Digital Repository Infrastructure Vision for European Research (DRIVER)

West Coast Centre renosterveld in the Western Cape of South Africa is highly fragmented and threatened due to conversion by agriculture, urbanization and the effects of invasive alien species. Currently, insufficient data on ecological processes and restoration priorities of this endangered vegetation type exist. Therefore, this thesis is an attempt to close knowledge gaps, starting with a review of renosterveld research in chapter one. Integrating available research results, the...

Heelemann, Steffen

2011-01-01

169

The classification, mapping and description of the vegetation of the Rooipoort Nature Reserve, Northern Cape, South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The need for a scientifically-based wildlife management plan and for more knowledge on vegetation led to an investigation into the plant ecology of the Rooipoort Nature Reserve. The main aim of this study was therefore to classify, describe and map the vegetation of the reserve. The floristic data were analysed according to the Braun-Blanquet procedure using the BBPC suite. The data analysis resulted in the identification of 15 communities that can be grouped into ten major community types. T...

Hugo Bezuidenhout

2009-01-01

170

[Feeding habits and trophic ecology of the fish Lutjanus griseus (Pisces: Lutjanidae) associated with submerged vegetation in Laguna de Términos, Campeche, Mexico].  

Science.gov (United States)

In Campeche, Mexico, the Laguna de Términos has Thalassia testudinum beds inhabited by the grey snapper, Lutjanus griseus (Linnaeus 1758). Along one year, we collected 994 individuals and 672 had food in their stomachs; we recorded number, weight, and frequency oftrophic groups, and the index of relative importance. Dominant food components were Farfantepenaeus duorarum and Palemonetes octaviae, Eucinostomus gula (Cuvier 1830) and Libinia dubia. Salinity and temperature were related to the number of individuals collected and with greater fish consumption by large L. griseus. The trophic niche breadth index was calculated for six size-classes of fish. The smallest and the largest fish had the lowest index values, whereas medium-size snappers had higher values. This snapper has a preference for habitats with submerged vegetation. The percentage of fish with food in their stomachs was higher during dark hours, providing evidence of the nocturnal habits of this fish. PMID:19086401

Guevara, Emma; Alvarez, Hernán; Mascaró, Maite; Rosas, Carlos; Sánchez, Alberto

2007-01-01

171

Vegetation growth monitoring under coal exploitation stress by remote sensing in the Bulianta coal mining area  

Energy Technology Data Exchange (ETDEWEB)

Coal exploitation inevitably damages the natural ecological environment through large scale underground exploitation which exhausts the surrounding areas and is the cause of surface subsidence and cracks. These types of damage seriously lower the underground water table. Deterioration of the environment has certainly an impact on and limits growth of vegetation, which is a very important indicator of a healthy ecological system. Dynamically monitoring vegetation growth under coal exploitation stress by remote sensing technology provides advantages such as large scale coverage, high accuracy and abundant information. A scatter plot was built by a TM (Thematic Mapper) infrared and red bands. A detailed analysis of the distributional characteristics of vegetation pixels has been carried out. Results show that vegetation pixels are affected by soil background pixels, while the distribution of soil pixels presents a linear pattern. Soil line equations were obtained mainly by linear regression. A new band, reflecting vegetation growth, has been obtained based on the elimination of the soil background. A grading of vegetation images was extracted by means of a density slice method. Our analysis indicates that before the exploitation of the Bulianta coal mining area, vegetation growth had gradually reduced; especially intermediate growth vegetation had been transformed into low vegetation. It may have been caused by the deterioration of the brittle environment in the western part of the mining area. All the same, after the start of coal production, vegetation growth has gradually improved, probably due to large scale aerial seeding. Remote sensing interpretation results proved to be consistent with the actual situation on the ground. From our research results we can not conclude that coal exploitation stress has no impact on the growth of vegetation. More detailed research on vegetation growth needs to be analyzed. 19 refs., 3 figs.

Xia Lu; Zhen-qi Hu; Wei-jie Liu; Xiao-yan Huang [China University of Mining & Technology, Beijing (China). Institute of Land Reclamation and Ecological Restoration

2007-09-15

172

Heavy metals in vegetable crops of Semey region  

International Nuclear Information System (INIS)

Heavy metals content in vegetable crops of Semey region is shown in this work and ecological valuing is given too. Influence of thermal treatment of the content of heavy metals in vegetable crops is revealed

2008-10-15

173

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 pre...

Calvet, J. -c; Gibelin, A. -l; Roujean, J. -l; Martin, E.; Le Moigne, P.; Douville, H.; Noilhan, J.

2007-01-01

174

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, base...

Calvet, Jean-christophe; Gibelin, Anne-laure; Roujean, Jean-louis; Martin, Eric; Le Moigne, Patrick; Douville, Herve?; Noilhan, Joe?l

2008-01-01

175

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 annua...

-c Calvet, J.; -l Gibelin, A.; -l Roujean, J.; Martin, E.; Le Moigne, P.; Douville, H.; Noilhan, J.

2008-01-01

176

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

-c Calvet, J.; -l Gibelin, A.; -l Roujean, J.; Martin, E.; Le Moigne, P.; Douville, H.; Noilhan, J.

2007-01-01

177

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 pr...

Calvet, J. -c; Gibelin, A. -l; Roujean, J. -l; Martin, E.; Le Moigne, P.; Douville, H.; Noilhan, J.

2008-01-01

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  

Directory of Open Access Journals (Sweden)

Full Text Available 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.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, by 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

2011-12-01

179

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.

180

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

 
 
 
 
181

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

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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

182

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

Directory of Open Access Journals (Sweden)

Full Text Available 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.

2002-01-01

183

Approaches to vegetation mapping and ecophysiological hypothesis testing using combined information from TIMS, AVIRIS, and AIRSAR  

Science.gov (United States)

The Tropical Rainforest Ecology Experiment (TREE) had two primary objectives: (1) to design a method for mapping vegetation in tropical regions using remote sensing and determine whether the result improves on available vegetation maps; and (2) to test a specific hypothesis on plant/water relations. Both objectives were thought achievable with the combined information from the Thermal Infrared Multispectral Scanner (TIMS), Airborne Visible/Infrared Imaging Spectrometer (AVIRIS), and Airborne Synthetic Aperture Radar (AIRSAR). Implicitly, two additional objectives were: (1) to ascertain that the range within each variable potentially measurable with the three instruments is large enough in the site, relative to the sensitivity of the instruments, so that differences between ecological groups may be detectable; and (2) to determine the ability of the three systems to quantify different variables and sensitivities. We found that the ranges in values of foliar nitrogen concentration, water availability, stand structure and species composition, and plant/water relations were large, even within the upland broadleaf vegetation type. The range was larger when other vegetation types were considered. Unfortunately, cloud cover and navigation errors compromised the utility of the TIMS and AVIRIS data. Nevertheless, the AIRSAR data alone appear to have improved on the available vegetation map for the study area. An example from an area converted to a farm is given to demonstrate how the combined information from AIRSAR, TIMS, and AVIRIS can uniquely identify distinct classes of land use. The example alludes to the potential utility of the three instruments for identifying vegetation at an ecological scale finer than vegetation types.

Oren, R.; Vane, G.; Zimmermann, R.; Carrere, V.; Realmuto, V.; Zebker, Howard A.; Schoeneberger, P.; Schoeneberger, M.

1991-01-01

184

[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

185

Lake Victoria wetlands and the ecology of the Nile tilapia, oreochromis niloticus linn,.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An ecological study of wetlands was undertaken in northern Lake Victoria (East Africa) between 1993 and 1996 with a major aim of characterising shallow vegetation-dominated interface habitats, and evaluating their importance for fish, in particular, for the stocked and socio-economically important Oreochromis niloticus LINNÉ (the Nile tilapia). From field and laboratory experiments, five major habitat types could be defined by the type of the dominant emergent macrophyte at the shore from th...

Balirwa, J. S.

1998-01-01

186

Soil, vegetation, and seed bank of a Sonoran Desert ecosystem along an exotic plant (Pennisetum ciliare) treatment gradient.  

Science.gov (United States)

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. PMID:23771285

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

2013-10-01

187

Ecological impact assessment  

International Nuclear Information System (INIS)

Quantitative problems in accomplishing ecological impact assessment with particular reference to defining population effects are discussed with some comments on the two approaches most commonly used, e.g., the experimental and simulation models. Some alternatives are suggested because both methods will probably fail to detect real population effects mostly due to poor understanding of ecosystems or because of the limitations inherent in field census methods. Most judgments of ecological impact are not quantitatively defensible but are qualitative, subjective, or political in nature. An examination of aggregates of data from various nuclear power plant sites may be one way to obtain enough replication to judge ecological impact. Thus, currently available data from such studies as well as appropriate demographic, vegetation, census, and bibliographic material could offer an interesting challenge to computer professionals if such an undertaking were contemplated. Present research programs at PNL and computer involvement are described. Future possibilities and directions are discussed. (U.S.)

1975-07-09

188

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.

Pinheiro, Eduardo Da Silva; Durigan, Giselda.

189

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  

Directory of Open Access Journals (Sweden)

Full Text Available 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.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 Station, 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

2009-09-01

190

Discrimination of vegetation types in alpine sites with ALOS PALSAR-, RADARSAT-2-, and lidar-derived information  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Natural vegetation monitoring in the alpine mountain range is a priority in the European Union in view of climate change effects. Many potential monitoring tools, based on advanced remote sensing sensors, are still not fully integrated in operational activities, such as those exploiting very high-resolution synthetic aperture radar (SAR) or light detection and ranging (lidar) data. Their testing is important for possible incorporation in routine monitoring and to increase the quantity and qua...

2013-01-01

191

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.

192

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)

2008-01-01

193

Transgenes sustain epigeal insect biodiversity in diversified vegetable farm systems.  

Science.gov (United States)

Many ecological studies have focused on the effects of transgenes in field crops, but few have considered multiple transgenes in diversified vegetable systems. We compared the epigeal, or soil surface-dwelling, communities of Coleoptera and Formicidae between transgenic and isoline vegetable systems consisting of sweet corn, potato, and acorn squash, with transgenic cultivars expressing Cry1(A)b, Cry3, or viral coat proteins. Vegetables were grown in replicated split plots over 2 yr with integrated pest management (IPM) standards defining insecticide use patterns. More than 77.6% of 11,925 insects from 1,512 pitfall traps were identified to species, and activity density was used to compare dominance distribution, species richness, and community composition. Measures of epigeal biodiversity were always equal in transgenic vegetables, which required fewer insecticide applications than their near isolines. There were no differences in species richness between transgenic and isoline treatments at the farm system and individual crop level. Dominance distributions were also similar between transgenic and isoline farming systems. Crop type, and not genotype, had a significant influence on Carabidae and Staphylinidae community composition in the first year, but there were no treatment effects in the second year, possibly because of homogenizing effects of crop rotations. Communities were more influenced by crop type, and possibly crop rotation, than by genotype. The heterogeneity of crops and rotations in diversified vegetable farms seems to aid in preserving epigeal biodiversity, which may be supplemented by reductions in insecticide use associated with transgenic cultivars. PMID:17349138

Leslie, T W; Hoheisel, G A; Biddinger, D J; Rohr, J R; Fleischer, S J

2007-02-01

194

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

195

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  

Directory of Open Access Journals (Sweden)

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

196

Mangrove Ecology and Deltaic Geomorphology: Tabasco, Mexico.  

Science.gov (United States)

There has been a spate of studies within the last two decades which have emphasized the strong relationship between landforms and vegetation. This is not a new theme in plant ecology, for many so-called classic studies emphasized the physiographic-ecologi...

B. G. Thom

1966-01-01

197

On the potential of long wavelength imaging radars for mapping vegetation types and woody biomass in tropical rain forests  

Science.gov (United States)

In the tropical rain forests of Manu, in Peru, where forest biomass ranges from 4 kg/sq m in young forest succession up to 100 kg/sq m in old, undisturbed floodplain stands, the P-band polarimetric radar data gathered in June of 1993 by the AIRSAR (Airborne Synthetic Aperture Radar) instrument separate most major vegetation formations and also perform better than expected in estimating woody biomass. The worldwide need for large scale, updated biomass estimates, achieved with a uniformly applied method, as well as reliable maps of land cover, justifies a more in-depth exploration of long wavelength imaging radar applications for tropical forests inventories.

Rignot, Eric J.; Zimmermann, Reiner; Oren, Ram

1995-01-01

198

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

199

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 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)

2005-05-08

200

Preliminary Ecological Survey of Microflora Inhabitant Different Types of Hydrophytes in Fresh Water Systems at Middle Egypt Belt with Reference to Physico-chemical Parameters and Phytochemistry  

Directory of Open Access Journals (Sweden)

Full Text Available Fungal as well as algal flora inhabiting different types of hydrophytes (floating, submerged and emerged in case of healthy and unhealthy ones and from different habitats represent different aquatic ecotypes in middle Egypt area (River Nile, channels, drains and pools were studied. The relations between fungal and algal flora were studied. Some in vivo experiments were done to analyze and confirm the in vitro observations. In addition to complete analysis of ecological parameters which may affect the abilities of microflora to colonize and inhabitant these hydrophytes, e.g. complete physical and chemical analysis of water of investigated sites, also phytochemical investigations of studied hydrophytes were conducted.

A.H. Abo El-lil

2003-01-01

 
 
 
 
201

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

202

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

1993-01-01

203

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

204

Analysis of phenoxyl-type N-methylcarbamate pesticide residues in vegetables by capillary zone electrophoresis with pre-column hydrolysis and amperometric detection.  

Science.gov (United States)

With systematic studies of pre-column thermalhydrolysis, a method is described for the determination of fivephenoxyl-type N-methylcarbamates (NMCs) (viz., propoxur, carbofuran, 3-hydroxy-carbofuran, carbaryl, and bendiocarb) in vegetables by capillary zone electrophoresis with amperometric detection. Effects of hydrolysis parameters such as alkali medium, temperature, and hydrolysis time, as well as separation conditions, are investigated. Under the optimum conditions, baseline separation of five hydrolysates is achieved within 16 min. Good calibration curves of propoxur, carbofuran, 3-hydroxy-carbofuran, carbaryl, and bendiocarb are obtained from 1.20x10(-7) to 5.00x10(-5) mol/L, and their detection limits (S/N=3) are 1.80x10(-8), 1.50x10(-8), 1.80x10(-8), 2.50x10(-8), and 1.80x10(-8) mol/L, respectively, which is approximately 20 approximately 50-fold more sensitive than those previously reported with a UV method. In the application of vegetable samples, the five NMCs are well determined. Average recoveries of 75 approximately 89% and 86 approximately 100% at fortified levels of 0.05 and 0.80 mg/kg are achieved with relative standard deviations of 2 approximately 6%, respectively. The method is sensitive, reproducible, and provides an alternative means for the analysis of phenoxyl-type NMC pesticide residues. PMID:18718137

Lin, Xucong; Hong, Qin; Wu, Xiaoping; Guo, Liangqia; Xie, Zenghong

2008-08-01

205

Metabolic ecology.  

Science.gov (United States)

Ecological theory that is grounded in metabolic currencies and constraints offers the potential to link ecological outcomes to biophysical processes across multiple scales of organization. The metabolic theory of ecology (MTE) has emphasized the potential for metabolism to serve as a unified theory of ecology, while focusing primarily on the size and temperature dependence of whole-organism metabolic rates. Generalizing metabolic ecology requires extending beyond prediction and application of standardized metabolic rates to theory focused on how energy moves through ecological systems. A bibliometric and network analysis of recent metabolic ecology literature reveals a research network characterized by major clusters focused on MTE, foraging theory, bioenergetics, trophic status, and generalized patterns and predictions. This generalized research network, which we refer to as metabolic ecology, can be considered to include the scaling, temperature and stoichiometric models forming the core of MTE, as well as bioenergetic equations, foraging theory, life-history allocation models, consumer-resource equations, food web theory and energy-based macroecology models that are frequently employed in ecological literature. We conclude with six points we believe to be important to the advancement and integration of metabolic ecology, including nomination of a second fundamental equation, complementary to the first fundamental equation offered by the MTE. PMID:24028511

Humphries, Murray M; McCann, Kevin S

2014-01-01

206

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  

Directory of Open Access Journals (Sweden)

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.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, durante 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.

MARILUZA GRANJA BARROS

2001-09-01

207

Riparian vegetation metrics as tools for guiding ecological restoration in riverscapes Descripteurs de la végétation rivulaire comme guide de la restauration écologique au sein des paysages de cours d’eau  

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Full Text Available Riparian woods are frequently fragmented and degraded, mainly as a consequence of land-cover related stresses, water diversion, regulation and invasive species. The need to enhance these systems towards their natural functioning has motivated numerous restoration efforts. However, river managers still need guidance on how to allocate scarce restoration resources, and to monitor and report the effectiveness of the restoration programmes. For this, the present work proposes a stepwise methodological procedure over spatial scales, using quantitative descriptors (metrics of the ecological condition of the riparian vegetation. This evaluation is based on the composition and cover of plant assemblages, species attributes, and spatial patterns, which can reflect the deviation of the structure and condition of the riparian zone from the near-natural state to an impaired situation. Landscape metrics obtained from high spatial resolution imagery are used for the evaluation of the spatial features of the riparian zone, followed by the calculation of a riparian multimetric index, based on field observations. The integration of multi-spatial scale information provided by landscape metrics and biological metrics is essential and recommended for decision support of end-users and to evaluate the success of restoration measures. La dégradation et la fragmentation fréquentes des bois rivulaires sont principalement dues à des pressions d’usage du sol, à des modes de gestions des écoulements de l’eau et à la concurrence par des espèces invasives. C’est ce besoin de retour à des fonctionnements plus proches des conditions naturelles qui a motivé nombre d’efforts de restauration. Toutefois les gestionnaires de cours d’eau sont demandeurs d’outils d’évaluation des programmes de restauration et des manières de gérer des ressources qui se raréfient. Pour cela, notre travail propose une méthode hiérarchisée à des échelles spatiales variées, par des descripteurs quantitatifs (métriques de l’état écologique de la végétation riparienne. Cette évaluation se fait à partir de la composition et du recouvrement des assemblages de plantes, des exigences spécifiques, et de leur répartition spatiale. Cette répartition spatiale est le reflet de l’écart de la structure et de l’état des berges, d’un état de référence quasi-naturel à une situation dégradée. Les métriques paysagères obtenues à partir d’une imagerie spatiale à haute résolution sont utilisées pour évaluer les particularités spatiales des berges, puis pour le calcul d’un indice rivulaire multifactoriel basé sur des observations de terrain. L’intégration d’une information spatiale multi-scalaire renseignée par des descripteurs du paysage est essentielle et recommandée comme support de décision pour les gestionnaires et pour évaluer le succès d’actions de restauration.

Teresa Ferreira M.

2011-11-01

208

Ecological bioavailability of permethrin and p,p'-DDT: toxicity depends on type of organic matter resource.  

Science.gov (United States)

Hydrophobic organic contaminants readily partition from aqueous to organic phases in aquatic systems with past research largely focusing on sediment. However, within many aquatic systems, matrices such as leaf material and detritus are abundant and ecologically important, as they may represent a primary exposure route for aquatic invertebrates. The objectives of the present study were to examine partitioning and toxicity to Hyalella azteca among permethrin and p,p'-DDT contaminated sediment, leaf, and a sediment-leaf mixture. Log organic carbon-water partitioning coefficients ranged from 4.21 to 5.82 for both insecticides, and were greatest within sediment and lowest in coarse leaf material. H. azteca lethal concentrations for 50% of the population (LC50s) ranged from 0.5 to 111?gg(-1) organic carbon, and were dependent on the matrix composition. The variation in sorption and toxicity among matrices common within stream ecosystems suggests that the ecological niche of aquatic organisms may be important for estimating risk of hydrophobic pesticides. PMID:23948608

de Perre, Chloé; Trimble, Andrew J; Maul, Jonathan D; Lydy, Michael J

2014-02-01

209

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.

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

210

Generic index of aquatic vegetation (IVAM) for a rapid assessment of ecological quality of Spanish rivers: taxonomic resolution and application to Castilla-La Mancha region; Indice Generico de Vegetacion Acuatica (IVAM): Propuesta de evaluacion rapida del estado ecologico de los rios ibericos en aplicacion de la Directiva Marco del Agua  

Energy Technology Data Exchange (ETDEWEB)

The Water Framework Directive proposes the use of aquatic flora as a valid bio indicator for assessing the ecological status of European rivers. Due to the lack of an aquatic vegetation index for Spanish rivers, we present an index to assess trophic status or eutrophication in rivers and streams. Thus, we calculated tolerance scores and indicator values for tax from nutrient levels. the index is called IVAM (Macroscopic Aquatic Vegetation Index). The index takes into account either macrophyte or microphytes (the latter making up macroscopic growth forms) including briophytes. The IVAM showed the best correlation with nutrients besides other quality indices, indicating a solid tool to assess trophic status or eutrophication. (Author) 15 refs.

Moreno, J. L.; Navarro, C.; Hera, J. de las

2005-07-01

211

Ecological economics  

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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

212

Coevolution of hydraulic, soil and vegetation processes in estuarine wetlands  

Science.gov (United States)

Estuarine wetlands of south eastern Australia, typically display a vegetation zonation with a sequence mudflats - mangrove forest - saltmarsh plains from the seaward margin and up the topographic gradient. Estuarine wetlands are among the most productive ecosystems in the world, providing unique habitats for fish and many terrestrial species. They also have a carbon sequestration capacity that surpasess terrestrial forest. Estuarine wetlands respond to sea-level rise by vertical accretion and horizontal landward migration, in order to maintain their position in the tidal frame. In situations in which buffer areas for landward migration are not available, saltmarsh can be lost due to mangrove encroachment. As a result of mangrove invasion associated in part with raising estuary water levels and urbanisation, coastal saltmarsh in parts of south-eastern Australia has been declared an endangered ecological community. Predicting estuarine wetlands response to sea-level rise requires modelling the coevolving dynamics of water flow, soil and vegetation. This paper presents preliminary results of our recently developed numerical model for wetland dynamics in wetlands of the Hunter estuary of NSW. The model simulates continuous tidal inflow into the wetland, and accounts for the effect of varying vegetation types on flow resistance. Coevolution effects appear as vegetation types are updated based on their preference to prevailing hydrodynamic conditions. The model also considers that accretion values vary with vegetation type. Simulations are driven using local information collected over several years, which includes estuary water levels, accretion rates, soil carbon content, flow resistance and vegetation preference to hydraulic conditions. Model results predict further saltmarsh loss under current conditions of moderate increase of estuary water levels.

Trivisonno, Franco; Rodriguez, Jose F.; Riccardi, Gerardo; Saco, Patricia; Stenta, Hernan

2014-05-01

213

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

214

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

2008-06-01

215

Distribution of grasshoppers (Othoptera: Acridoidea) in the Tapacurá ecological station (São Lourenço da Mata, PE / Brazil) Distribuição de gafanhotos (Othoptera: Acridoidea) na estação ecológica do tapacurá (São Lourenço Da Mata, PE)  

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Over the last five years, collection and periodic observation in the Tapacurá Ecological Station, São Lourenço da Mata, Pernambuco, Brazil, have been carried out to produce a systematic ecological inventory of grasshopper distribution within the station based on the classifying criteria for Acridoidea, providing new data on families, subfamilies, tribes, genera and species related to the various types of vegetation and environments the station affords.Através de procedimento de coleta...

Av, Almeida; Cag, Ca?mara

2008-01-01

216

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

217

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish 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 zo [...] na 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. Abstract in english 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.

Cruz-Elizalde, Raciel; Ramírez-Bautista, Aurelio.

218

Warfare Ecology  

Science.gov (United States)

Among human activities causing ecological change, war is both intensive and far-reaching. Yet environmental research related to warfare is limited in depth and fragmented by discipline. Here we (1) outline a field of study called "warfare ecology," (2) provide a taxonomy of warfare useful for organizing the field, (3) review empirical studies, and (4) propose research directions and policy implications that emerge from the ecological study of warfare. Warfare ecology extends to the three stages of warfare - preparations, war, and postwar activities - and treats biophysical and socioeconomic systems as coupled systems. A review of empirical studies suggests complex relationships between warfare and ecosystem change. Research needs include the development of theory and methods for examining the cascading effects of warfare on specific ecosystems. Policy implications include greater incorporation of ecological science into military planning and improved rehabilitation of postwar ecosystem services, leading to increased peace and security.

Gary E. Machlis (University of Idaho;); Thor Hanson (University of Idaho;)

2008-09-01

219

Exposure of trees to drought-induced die-off is defined by a common climatic threshold across different vegetation types.  

Science.gov (United States)

Increases in drought and temperature stress in forest and woodland ecosystems are thought to be responsible for the rise in episodic mortality events observed globally. However, key climatic drivers common to mortality events and the impacts of future extreme droughts on tree survival have not been evaluated. Here, we characterize climatic drivers associated with documented tree die-off events across Australia using standardized climatic indices to represent the key dimensions of drought stress for a range of vegetation types. We identify a common probabilistic threshold associated with an increased risk of die-off across all the sites that we examined. We show that observed die-off events occur when water deficits and maximum temperatures are high and exist outside 98% of the observed range in drought intensity; this threshold was evident at all sites regardless of vegetation type and climate. The observed die-off events also coincided with at least one heat wave (three consecutive days above the 90th percentile for maximum temperature), emphasizing a pivotal role of heat stress in amplifying tree die-off and mortality processes. The joint drought intensity and maximum temperature distributions were modeled for each site to describe the co-occurrence of both hot and dry conditions and evaluate future shifts in climatic thresholds associated with the die-off events. Under a relatively dry and moderate warming scenario, the frequency of droughts capable of inducing significant tree die-off across Australia could increase from 1 in 24 years to 1 in 15 years by 2050, accompanied by a doubling in the occurrence of associated heat waves. By defining commonalities in drought conditions capable of inducing tree die-off, we show a strong interactive effect of water and high temperature stress and provide a consistent approach for assessing changes in the exposure of ecosystems to extreme drought events. PMID:24772285

Mitchell, Patrick J; O'Grady, Anthony P; Hayes, Keith R; Pinkard, Elizabeth A

2014-04-01

220

Dissolved inorganic nitrogen pools and surface flux under different brackish marsh vegetation types, common reed (Phragmites australis) and salt hay (Spartina patens)  

Science.gov (United States)

The current expansion of Phragmites australis into the high marsh shortgrass (Spartina patens, Distichlis spicata) communities of eastern U.S. salt marshes provided an opportunity to identify the influence of vegetation types on pools and fluxes of dissolved inorganic nitrogen (DIN). Two brackish tidal marshes of the National Estuarine Research Reserve system were examined, Piermont Marsh of the Hudson River NERR in New York and Hog Island in the Jacques Coustaeu NERR of New Jersey. Pools of DIN in porewater and rates of DIN surface flux were compared in replicated pairs of recently-expanded P. australis and neighboring S. patens-dominated patches on the high marsh surface. Both marshes generally imported nitrate (NO3-) and exported ammonium (NH4+), such that overall DIN was exported. No differences in surface exchange of NO3- or NH4+ were observed between vegetation types. Depth-averaged porewater NH4+ concentrations over the entire growing season were 56% lower under P. australis than under S. patens (average 1.4 vs. 3.2 mg NH4+ L-1) with the most profound differences in November. Porewater profiles showed an accumulation of NH4+ at depth in S. patens and constant low concentrations in P. australis from the soil surface to 50 cm depth, with no significant differences in porewater salinity. Despite these profound differences in porewater, NH 4+ diffusion from soils of P. australis and S. patens were not measurably different, were similar to other published rates, and were well below estimated rates based on passive diffusion alone. Rapid adsorption and uptake by litter and microbes in surface soils of both communities may buffer NH4+ loss to flooding tides in both communities, thereby reducing the impact of P. australis invasion on NH4+ flux to flooding waters. ?? Springer 2005.

Windham-Myers, L.

2005-01-01

 
 
 
 
221

Monitoring vegetation responses to drought -- linking Remotely-sensed Drought Indices with Meteorological drought indices  

Science.gov (United States)

Abstract: Effectively monitoring vegetation drought is of great significance in ecological conservation and agriculture irrigation at the regional scale. Combining meteorological drought indices with remotely sensed drought indices can improve tracking vegetation dynamic under the threat of drought. This study analyzes the dynamics of spatially-defined Temperature Vegetation Dryness Index (TVDI) and temporally-defined Vegetation Health Index (VHI) from remotely sensed NDVI and LST datasets in the dry spells in Southwest China. We analyzed the correlation between remotely sensed drought indices and meteorological drought index of different time scales. The results show that TVDI was limited by the spatial variations of LST and NDVI, while VHI was limited by the temporal variations of LST and NDVI. Station-based buffering analysis indicates that the extracted remotely sensed drought indices and Standard Precipitation Index (SPI) could reach stable correlation with buffering radius larger than 35 km. Three factors affect the spatiotemporal relationship between remotely sensed drought indices and SPI: i) different vegetation types; ii) the timescale of SPI; and iii) remote sensing data noise. Vegetation responds differently to meteorological drought at various time scales. The correlation between SPI6 and VHI is more significant than that between SPI6 and TVDI. Spatial consistency between VHI and TVDI varies with drought aggravation. In early drought period from October to December, VHI and TVDI show limited consistency due to the low quality of remotely sensed images. The study helps to improve monitoring vegetation drought using both meteorological drought indices and remotely sensed drought indices.

Wang, H.; Lin, H.; Liu, D.

2013-12-01

222

Connectivity processes and riparian vegetation of the upper Paraná River, Brazil  

Science.gov (United States)

In fluvial systems, the relationship between a dominant variable (e.g. flood pulse) and its dependent ones (e.g. riparian vegetation) is called connectivity. This paper analyzes the connectivity elements and processes controlling riparian vegetation for a reach of the upper Paraná River (Brazil) and estimates the future changes in channel-vegetation relationship as a consequence of the managing of a large dam. The studied reach is situated 30 km downstream from the Porto Primavera Dam (construction finished in 1999). Through aerial photography (1:25,000, 1996), RGB-CBERS satellite imagery and a previous field botany survey it was possible to elaborate a map with the five major morpho-vegetation units: 1) Tree-dominated natural levee, 2) Shrubby upper floodplain, 3) Shrub-herbaceous mid floodplain, 4) Grass-herbaceous lower floodplain and 5) Shrub-herbaceous flood runoff channel units. By use of a detailed topographic survey and statistical tools each morpho-vegetation type was analyzed according to its connectivity parameters (frequency, recurrence, permanence, seasonality, potamophase, limnophase and FCQ index) in the pre- and post-dam closure periods of the historical series. Data showed that most of the morpho-vegetation units were predicted to present changes in connectivity parameters values after dam closing and the new regime could affect, in different intensity, the river ecology and particularly the riparian vegetation. The methods used in this study can be useful for dam impact studies in other South American tropical rivers.

Stevaux, José C.; Corradini, Fabrício A.; Aquino, Samia

2013-10-01

223

Vegetative cover for low level radioactive waste sites  

Energy Technology Data Exchange (ETDEWEB)

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.

Salvo, S. Keith (USDA Soil Conservation Service, Raleigh, NC (United States))

1994-06-01

224

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

225

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

2007-01-01

226

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

227

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

228

Vegetation emphasized on Taihang Shan  

Energy Technology Data Exchange (ETDEWEB)

This article explains how increasing vegetation in a Chinese province can reduce soil erosion. During 1982 there was a silt accumulation of 15.9 million cubic meters in the 11 large, medium and small reservoirs throughout the mountainous district, and some 93,000 tons of nitrogen, phosphorus, potassium and organic fertilizers were washed away. Large forests can reduce or delay flood crests and can increase water supplies during normal or dry seasons. Closing off mountains to grow trees increases vegetation, protects the ecological environment, prevents erosion and improves economic results and the living standards of the populace of mountainous districts. If grass is grown on barren mountains and slopes, the soil will then have water and nutrients, and an excellent ecological environment for afforestation can be created.

Sun Jingcai

1983-08-11

229

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.

230

Earlier-Season Vegetation Has Greater Temperature Sensitivity of Spring Phenology in Northern Hemisphere  

Science.gov (United States)

In recent decades, satellite-derived start of vegetation growing season (SOS) has advanced in many northern temperate and boreal regions. Both the magnitude of temperature increase and the sensitivity of the greenness phenology to temperature–the phenological change per unit temperature–can contribute the advancement. To determine the temperature-sensitivity, we examined the satellite-derived SOS and the potentially effective pre-season temperature (Teff) from 1982 to 2008 for vegetated land between 30°N and 80°N. Earlier season vegetation types, i.e., the vegetation types with earlier SOSmean (mean SOS for 1982–2008), showed greater advancement of SOS during 1982–2008. The advancing rate of SOS against year was also greater in the vegetation with earlier SOSmean even the Teff increase was the same. These results suggest that the spring phenology of vegetation may have high temperature sensitivity in a warmer area. Therefore it is important to consider temperature-sensitivity in assessing broad-scale phenological responses to climatic warming. Further studies are needed to explore the mechanisms and ecological consequences of the temperature-sensitivity of start of growing season in a warming climate.

Shen, Miaogen; Tang, Yanhong; Chen, Jin; Yang, Xi; Wang, Cong; Cui, Xiaoyong; Yang, Yongping; Han, Lijian; Li, Le; Du, Jianhui; Zhang, Gengxin; Cong, Nan

2014-01-01

231

Comparison of deep soil moisture in two re-vegetation watersheds in semi-arid regions  

Science.gov (United States)

Soil moisture stored below rainfall infiltration depth is a reliable water resource for plant growth in semi-arid ecosystems. Along with the large-scale ecological restoration in Chinese Loess Plateau, identifying the ecohydrological response to human-introduced vegetation restoration has become an important issue in current research. In this study, soil moisture data in depth of 0-5 m was obtained by field observation and geostatistical method in two neighboring re-vegetation watersheds. Profile characteristics and spatial pattern of soil moisture was compared between different land use types, transects, and watersheds. The results showed that: (1) Introduced vegetation drastically decreased deep soil moisture when compared with farmland and native grassland. No significant differences in deep soil moisture were found between different introduced vegetation types. (2) An analysis of differences in soil moisture for different land use patterns indicated that land use had significant influence on deep soil moisture spatial variability. Land use structure determined the soil moisture condition and its spatial variation. (3) Vegetation restoration with introduced plants diminished the spatial heterogeneity of deep soil moisture on watershed scale. The improvement of land use management was suggested to improve the water management and maintain the sustainability of vegetation restoration.

Yang, Lei; Chen, Liding; Wei, Wei; Yu, Yang; Zhang, Handan

2014-05-01

232

VEGETABLE MARKETING – A SYNTHETIC EVALUATION  

Directory of Open Access Journals (Sweden)

Full Text Available The paper studies the role of business relationships in the Romanian vegetable supply chain. The analysis reveals that informal contractual relationships are prevalent on the market while in many cases contractual enforcement is at stake. This situation leads to increased uncertainty in terms of what vegetable to produce and where to sell and it negatively impacts the farmers’ revenues and investment decision. The paper employs a qualitative analysis in order to assess the main vegetable commercialization channels including vegetable processing companies and the type of contractual relationship between parts.

CORNELIA ALBOIU

2009-05-01

233

Radionuclide accumulation peculiarities demonstrated by vegetable varieties  

International Nuclear Information System (INIS)

This study focused on ecological and genetic aspects of radionuclide accumulation demonstrated by a number of vegetable varieties. The researches resulted in determining the cabbage varieties which were characterised by the minimal level of radionuclide accumulation. It was shown that the above varieties manifested the relation between radionuclide accumulation and morphobiological characteristics such as vegetation period duration and yield criteria. The study specified the genotypes with high ecological stability as regards to radionuclide accumulation: 'Beloruskaya 85' cabbage and 'Dokhodny' tomato showed the best response to Cs 137, while 'Beloruskaya 85', 'Rusinovka', 'Amager 611' cabbage varieties and 'Sprint' tomato showed the minimal level of Sr 90 accumulation. (authors)

2004-01-01

234

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.)

1981-01-01

235

Evidence for ecological divergence across a mosaic of soil types in an Amazonian tropical tree: Protium subserratum (Burseraceae).  

Science.gov (United States)

Soil heterogeneity is an important driver of divergent natural selection in plants. Neotropical forests have the highest tree diversity on earth, and frequently, soil specialist congeners are distributed parapatrically. While the role of edaphic heterogeneity in the origin and maintenance of tropical tree diversity is unknown, it has been posited that natural selection across the patchwork of soils in the Amazon rainforest is important in driving and maintaining tree diversity. We examined genetic and morphological differentiation among populations of the tropical tree Protium subserratum growing parapatrically on the mosaic of white-sand, brown-sand and clay soils found throughout western Amazonia. Nuclear microsatellites and leaf morphology were used to (i) quantify the extent of phenotypic and genetic divergence across habitat types, (ii) assess the importance of natural selection vs. drift in population divergence, (iii) determine the extent of hybridization and introgression across habitat types, (iv) estimate migration rates among populations. We found significant morphological variation correlated with soil type. Higher levels of genetic differentiation and lower migration rates were observed between adjacent populations found on different soil types than between geographically distant populations on the same soil type. PST -FST comparisons indicate a role for natural selection in population divergence among soil types. A small number of hybrids were detected suggesting that gene flow among soil specialist populations may occur at low frequencies. Our results suggest that edaphic specialization has occurred multiple times in P. subserratum and that divergent natural selection across edaphic boundaries may be a general mechanism promoting and maintaining Amazonian tree diversity. PMID:24703227

Misiewicz, Tracy M; Fine, Paul V A

2014-05-01

236

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

1993-01-01

237

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.

238

Fruit and vegetable intake, as reflected by serum carotenoid concentrations, predicts reduced probability of polychlorinated biphenyl-associated risk for type 2 diabetes: National Health and Nutrition Examination Survey 2003-2004.  

Science.gov (United States)

Type 2 diabetes has been shown to occur in response to environmental and genetic influences, among them nutrition; food intake patterns; sedentary lifestyle; body mass index; and exposure to persistent organic pollutants, such as polychlorinated biphenyls (PCBs). Nutrition is essential in the prevention and management of type 2 diabetes and has been shown to modulate the toxicity of PCBs. Serum carotenoid concentrations, considered a reliable biomarker of fruit and vegetable intake, are associated with the reduced probability of chronic diseases, such as type 2 diabetes and cardiovascular disease. Our hypothesis is that fruit and vegetable intake, reflected by serum carotenoid concentrations, is associated with the reduced probability of developing type 2 diabetes in US adults with elevated serum concentrations of PCBs 118, 126, and 153. This cross-sectional study used the Center for Disease Control and Prevention database, National Health and Nutrition Examination Survey 2003-2004, in logistic regression analyses. Overall prevalence of type 2 diabetes was approximately 11.6% depending on the specific PCB. All 3 PCBs were positively associated with the probability of type 2 diabetes. For participants at higher PCB percentiles (eg, 75th and 90th) for PCB 118 and 126, increasing serum carotenoid concentrations were associated with a smaller probability of type 2 diabetes. Fruit and vegetable intake, as reflected by serum carotenoid concentrations, predicted notably reduced probability of dioxin-like PCB-associated risk for type 2 diabetes. PMID:24774064

Hofe, Carolyn R; Feng, Limin; Zephyr, Dominique; Stromberg, Arnold J; Hennig, Bernhard; Gaetke, Lisa M

2014-04-01

239

The classification, mapping and description of the vegetation of the Rooipoort Nature Reserve, Northern Cape, South Africa  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english The need for a scientifically-based wildlife management plan and for more knowledge on vegetation led to an investigation into the plant ecology of the Rooipoort Nature Reserve. The main aim of this study was therefore to classify, describe and map the vegetation of the reserve. The floristic data w [...] ere analysed according to the Braun-Blanquet procedure using the BBPC suite. The data analysis resulted in the identification of 15 communities that can be grouped into ten major community types. This resulted in five ecology-based management units, which could assist with the compilation of an ecologically sound management plan for the reserve in order to achieve sustainable utilisation of the natural resources. The Rooipoort Nature Reserve is one of the oldest and largest private nature reserves in South Africa and as such deserves to be conserved and protected. The riverine and pan vegetation communities are considered to be endangered and are in need of special conservation and protection. CONSERVATION IMPLICATION: The results suggest five management units, which will assist in the compilation of an ecologically sound management plan for the RNR, in order to allow sustainable utilization of natural resources.

Bezuidenhout, Hugo.

240

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

 
 
 
 
241

Economic and ecological outcomes of flexible biodiversity offset systems.  

Science.gov (United States)

The commonly expressed goal of biodiversity offsets is to achieve no net loss of specific biological features affected by development. However, strict equivalency requirements may complicate trading of offset credits, increase costs due to restricted offset placement options, and force offset activities to focus on features that may not represent regional conservation priorities. Using the oil sands industry of Alberta, Canada, as a case study, we evaluated the economic and ecological performance of alternative offset systems targeting either ecologically equivalent areas (vegetation types) or regional conservation priorities (caribou and the Dry Mixedwood natural subregion). Exchanging dissimilar biodiversity elements requires assessment via a generalized metric; we used an empirically derived index of biodiversity intactness to link offsets with losses incurred by development. We considered 2 offset activities: land protection, with costs estimated as the net present value of profits of petroleum and timber resources to be paid as compensation to resource tenure holders, and restoration of anthropogenic footprint, with costs estimated from existing restoration projects. We used the spatial optimization tool MARXAN to develop hypothetical offset networks that met either the equivalent-vegetation or conservation-priority targets. Networks that required offsetting equivalent vegetation cost 2-17 times more than priority-focused networks. This finding calls into question the prudence of equivalency-based systems, particularly in relatively undeveloped jurisdictions, where conservation focuses on limiting and directing future losses. Priority-focused offsets may offer benefits to industry and environmental stakeholders by allowing for lower-cost conservation of valued ecological features and may invite discussion on what land-use trade-offs are acceptable when trading biodiversity via offsets. Resultados Económicos y Ecológicos de Sistemas de Compensación de Biodiversidad Flexible Habib et al. PMID:23869724

Habib, Thomas J; Farr, Daniel R; Schneider, Richard R; Boutin, Stan

2013-12-01

242

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

243

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

244

Ecological Biology (Program Description)  

Science.gov (United States)

... Environmental Biology Ecological Biology Description The Ecological Biology Cluster supports ... findings into new paradigms. The Ecological Biology Cluster funds research in the following areas ...

245

ECOLOGICAL EDUCATION  

Directory of Open Access Journals (Sweden)

Full Text Available While in most emerging and developing countries, the population has a lower ecological footprint in the developed countries have a larger footprint.There is also an alarming contrast between a person perception of her liability for damages to its environment and its actual size. These misconceptions may have their source in the absence of awareness of risks from climate change, culture or religion.The purpose of this study is to analyze the situation at the international and Romanian level and to draw attention on the necessity of un ecological education.

GABRIELA GYONGY MIHUT

2011-04-01

246

Political ecology  

International Nuclear Information System (INIS)

Using facts and examples, this didactically structures textbook gives an insight into the extent and consequences of the damage to the environment, with the subjects - fundamentals of ecology; - population and food problems; - the energy problem; - economic growth; scarcity of resources, recycling; - ground, water, and air pollution, - city and traffic problems; - work protection and medical care; - political alternatives and 'soft technologies'. The analysis of the political and economic reasons is combined with social and technical alternatives from which demands to be made and measures to be taken can be derived for individuals, citizens' interest groups, political groups and trade unions. Teaching models intend to help teachers to work on specific problems of ecology. (orig.)

1979-01-01

247

Ecological investigation of three geophytes in the Deltaic Mediterranean coast of Egypt.  

Science.gov (United States)

This study was conducted to investigate the ecological features of three geophytes namely Asparagus stipularis, Cyperus capitatus and Stipagrostis lanata which grow naturally in the Nile Delta coast of Egypt. C. capitatus and S. lanata are growing in non-saline sandy soils and can tolerate drought stress while, A. stipularis is growing in saline and non-saline sandy and calcareous clay soils and can tolerate drought and salt stress. Multivariate analysis of the vegetation of 100 sampled stands supporting growth of the three geophytic species in the study area led to the recognition of four vegetation groups namely, (A) Alhagi graecorum, (B) Cyperus capitatus, (C) Lycium schweinfurthii var. schweinfurthii-Asparagus stipularis and (D) Juncus acutus subsp. acutus. Vegetationally, the vegetation groups associated with the three species can be distinguished into two community types. The first one is psammophytic community comprising vegetation groups A and B that may represent the non-saline sand formations (flats, hummocks and dunes). The second one is halophytic community including vegetation groups C and D that may represent the saline sand flats and salt marsh habitat types, respectively. Sodium adsorption ratio, electrical conductivity, sodium cation, chlorides, silt and sand fractions, pH value, moisture content, bicarbonates and available phosphorus were the most effective soil factors that controlling the abundance and distribution of the plant communities associated with the investigated geophytes. This study showed the ecological features of the selected geophytes in terms of their habitats, associated plant communities and the most edaphic factors controlling their richness and distribution in the study area. PMID:24506033

Maswada, Hanafey F; Elzaawely, Abdelnaser A

2013-12-01

248

Ecological Investigation of Three Geophytes in the Deltaic Mediterranean Coast of Egypt  

Directory of Open Access Journals (Sweden)

Full Text Available This study was conducted to investigate the ecological features of three geophytes namely Asparagus stipularis, Cyperus capitatus and Stipagrostis lanata which grow naturally in the Nile Delta coast of Egypt. C. capitatus and S. lanata are growing in non-saline sandy soils and can tolerate drought stress while, A. stipularis is growing in saline and non-saline sandy and calcareous clay soils and can tolerate drought and salt stress. Multivariate analysis of the vegetation of 100 sampled stands supporting growth of the three geophytic species in the study area led to the recognition of four vegetation groups namely, (A Alhagi graecorum, (B Cyperus capitatus, (C Lycium schweinfurthii var. schweinfurthii-Asparagus stipularis and (D Juncus acutus subsp. acutus. Vegetationally, the vegetation groups associated with the three species can be distinguished into two community types. The first one is psammophytic community comprising vegetation groups A and B that may represent the non-saline sand formations (flats, hummocks and dunes. The second one is halophytic community including vegetation groups C and D that may represent the saline sand flats and salt marsh habitat types, respectively. Sodium adsorption ratio, electrical conductivity, sodium cation, chlorides, silt and sand fractions, pH value, moisture content, bicarbonates and available phosphorus were the most effective soil factors that controlling the abundance and distribution of the plant communities associated with the investigated geophytes. This study showed the ecological features of the selected geophytes in terms of their habitats, associated plant communities and the most edaphic factors controlling their richness and distribution in the study area.

Abdelnaser A. Elzaawely

2013-01-01

249

Ecological profiles of wetland plant species in the northern Apennines (N. Italy)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Eighteen selected species occurring in the wetlands of the northern Apennines were studied by the ecological profile method. By this method, it is possible to identify the ecological factors mostly influencing species distribution within a particular vegetation. Moreover, it is possible to evaluate both ecological amplitude and ecological preferences of species. Ecological profiles were built for three factors (altitude, pH and electrical conductivity) from a data set of 265 phytosociological...

Petraglia, Alessandro; Tomaselli, Marcello

2003-01-01

250

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)

2002-01-01

251

Studying the effect of elevation and edaphic variables on vegetation composition in Khezrabad rangelands using principal component analysis (PCA  

Directory of Open Access Journals (Sweden)

Full Text Available A major scientific challenge in plant ecology is to identify and quantify the strength of environmental factors that are responsible for the distribution and abundance of plant species within and among ecosystems. Hence, this study is focused on relation between plant communities and environmental variables in Khezrabad region of Iran. Based on field surveys, eight vegetation types including Artemisia sieberi-Acantholimon erinaceum, Artemisia sieberi-Hertia angustifolia, Artemisia sieberi-Launea acanthodes, Artemisia sieberi-Salsola tomentosa, Artemisia sieberi-Zygophyllum atriplicoides, Artemisia aucheri-Astrgalus albispinus, Artemisia sieberi-Fortuynia bungei, Haloxylon aphyllum were identified. With respecting to the present variance between vegetation and environmental factors, four samples were established in each vegetation type in 0–30 cm depth. The studied soil variables affecting plant communities were texture, EC, pH, Na+, k+, Cl-, Ca2+, Mg2+, SP, O.M, CaCO3, HCO3 - and CEC. Among the topographic conditions, elevation was recorded in sampling regions as well. Data matrix of environmental factors and vegetation type was made using the windows (ver. 4.17 of PC-ORD. Results according to PCA showed that in the study area, among different environmental factors, the distribution of vegetation types was most strongly correlated with some agents such as soil texture, salinity and sodicity. In fact, soil texture controls distribution of plant species by affecting moisture availability, ventilation and distribution of plant roots. Beside, soil salinity and sodicity because of habitat condition, plant ecological needs and tolerance range can have negative affect on plant diversity. In addition, results indicated that increasing of elevation had negative effect on plant distribution. However, soil characteristics have more influence on vegetation separation than to the elevation in this study.

Ruhollah TAGHIZADEH MEHRJARDI

2009-11-01

252

Vegetation Analysis of Sutan-Chay Basin in Arasbaran  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Problem statement: Plants associations differ in relation to environmental gradients. Therefore, it is necessary to study the interaction between ecological factors and vegetation. Approach: In this study vegetation and flora of Sutan-Chay Basin in Arasbaran was investigated using Braun Blanquet method as physiognomic floristic. Sampling of soil and vegetation was carried out by selecting areas with homogenous plant compositions. The surface area of releves was determined using ...

Gajoti, T. E.; Haciyev, V.; Javanshir, A.; Nosrati, H.; Haghighi, A. R.; Eimanifar, A.; Stewart, N. J.

2010-01-01

253

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

254

Discrepancies among ecological, household, and individual data on fruits and vegetables consumption in Brazil Discrepância entre dados ecológicos, domiciliares e individuais sobre o consumo de frutas e hortaliças no Brasil  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Information on fruits and vegetables consumption in Brazil in the three levels of dietary data was analyzed and compared. Data about national supply came from Food Balance Sheets compiled by the FAO; household availability information was obtained from the Brazilian National Household Budget Survey (HBS); and actual intake information came from a large individual dietary intake survey that was representative of the adult population of São Paulo city. All sources of information were collected...

2010-01-01

255

The role of plant type and salinity in the selection for the denitrifying community structure in the rhizosphere of wetland vegetation.  

Science.gov (United States)

Coastal wetlands, as transient links from terrestrial to marine environments, are important for nitrogen removal by denitrification. Denitrification strongly depends on both the presence of emergent plants and the denitrifier communities selected by different plant species. In this study, the effects of vegetation and habitat heterogeneity on the community of denitrifying bacteria were investigated in nine coastal wetlands in two preserved areas of Spain. Sampling locations were selected to cover a range of salinity (0.81 to 31.3 mS/cm) and nitrate concentrations (0.1 to 303 ?M NO3-), allowing the evaluation of environmental variables that select for denitrifier communities in the rhizosphere of Phragmites sp., Ruppia sp., and Paspalum sp. Potential nitrate reduction rates were found to be dependent on the sampling time and plant species and related to the denitrifier community structure, which was assessed by terminal restriction fragment length polymorphism analysis of the functional genes nirS, nirK and nosZ. The results showed that denitrifier community structure was also governed by plant species and salinity, with significant influences of other variables, such as sampling time and location. Ruppia sp. and Phragmites sp. selected for certain communities, whereas this was not the case for Paspalum sp. The plant species effect was strongest on nirK-type denitrifiers, whereas water carbon content was a significant factor defining the structure of the nosZ-harboring community. The differences recognized using the three functional gene markers indicated that different drivers act on denitrifying populations capable of complete denitrification, compared to the overall denitrifier community. This finding may have implications for emissions of the greenhouse gas nitrous oxide. PMID:22847270

Bañeras, Luís; Ruiz-Rueda, Olaya; López-Flores, Rocío; Quintana, Xavier D; Hallin, Sara

2012-06-01

256

Are tree ontogenetic structure and allometric relationship independent of vegetation formation type? A case study with Cordia oncocalyx in the Brazilian caatinga  

Science.gov (United States)

In temperate and tropical rainforests, ontogenetic structure and allometry during tree ontogeny are often associated with light gradients. Light is not considered a limiting resource in deciduous thorny woodland (DTW), but establishment and growth occur during a short rainy period, when the canopy is fully leaved and light in the understory may be modified. Our aim was to investigate whether the light gradient in DTW and the biomechanical limitations of tree growth would be enough to produce an ontogenetic structure and allometric growth similar to rainforest canopy trees. We investigated the ontogenetic stages and diameter-height relationship of Cordia oncocalyx (Boraginaceae), a dominant canopy tree of the DTW of semiarid northeastern Brazil. We tagged, measured and classified the ontogenetic stages of 2.895 individuals in a 1 ha area (5°6'58.1?S and 40°52'19.4?W). In the rainy season only 4.7% of the light falling on the canopy reached the ground. Initial ontogenetic stages, mainly infant (50.9%) and seedling (42.1%), were predominant in the population, with the remaining 7% distributed among juvenile, immature, virginile and reproductive. The ontogenetic structure was similar to that of rainforest tree species, but the population formed both permanent seed and infant banks in response to long dry periods and erratic rainy spells. Like many other Boraginaceae tree species in tropical rainforests, C. oncocalyx has a Prévost architectural model, but allometric growth was quite different from rainforest trees. C. oncocalyx invested slightly more in diameter at first, then in height and finally invested greatly in diameter and attained an asymptotic height. The continued high investment in diameter growth at late stages and the asymptotic height point to low tree density and more frequent xylem embolism as the main drivers of tree allometric shape in DTW. This indicates that tree ontogenetic structure and allometric relationships depend on vegetation formation type.

Silveira, Andréa P.; Martins, Fernando R.; Araújo, Francisca S.

2012-08-01

257

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 de 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

258

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.

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

259

[Review of dynamic global vegetation models (DGVMs)].  

Science.gov (United States)

Dynamic global vegetation model (DGVM) is an important and efficient tool for study on the terrestrial carbon circle processes and vegetation dynamics. This paper reviewed the development history of DGVMs, introduced the basic structure of DGVMs, and the outlines of several world-widely used DGVMs, including CLM-DGVM, LPJ, IBIS and SEIB. The shortages of the description of dynamic vegetation mechanisms in the current DGVMs were proposed, including plant functional types (PFT) scheme, vegetation competition, disturbance, and phenology. Then the future research directions of DGVMs were pointed out, i. e. improving the PFT scheme, refining the vegetation dynamic mechanism, and implementing a model inter-comparison project. PMID:24765870

Che, Ming-Liang; Chen, Bao-Zhang; Wang, Ying; Guo, Xiang-Yun

2014-01-01

260

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  

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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...

Denes Bajzak; Roberts, Bruce A.

2011-01-01

 
 
 
 
261

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  

Directory of Open Access Journals (Sweden)

Full Text Available 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 distrófico 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.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 groundcover 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

2008-06-01

262

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.

263

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

1994-01-01

264

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

Energy Technology Data Exchange (ETDEWEB)

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.

Stegen, J.A.

1994-01-17

265

Ecology of Drosophila aggregation pheromone  

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Many insect species use an aggregation pheromone to form groups with conspecifics in certain localities of the environment. This type of behaviour has a variety of implications for ecological interactions, both directly through the effect of the pheromone on the behaviour of con- and heterospecifics, and indirectly through the consequential aggregative distributions that may affect species interactions. The evolutionary ecology of the use of aggregation pheromone has received o...

Wertheim, B.

2001-01-01

266

Industrial ecology.  

Science.gov (United States)

Industrial ecology addresses issues that will impact future production, use, and disposal technologies; proper use of the concept should reduce significantly the resources devoted to potential remediation in the future. This cradle-to-reincarnation production philosophy includes industrial processes that are environmentally sound and products that are environmentally safe during use and economically recyclable after use without adverse impact on the environment or on the net cost to society. This will require an industry-university-government round table to set the strategy and agenda for progress. PMID:11607254

Patel, C K

1992-02-01

267

Flow resistance models for flexible submerged vegetation  

Science.gov (United States)

SummaryThis paper investigates the variation of hydraulic roughness parameters with flow depth for submerged flexible vegetation. In an experimental study flexible grass canopies are used to examine the impact of stem height, grass type and degree of submergence on the flow resistance properties. Results reveal that Manning's n roughness coefficient increases with decreasing flow depth reaching an asymptotic constant at lower levels of vegetation submergence. Data suggest that the value of the constant is dependent on the vegetation height and the vegetation properties. Currently the n- UR method underpredicts the Manning's n and the data from this study extends the USDA method for lower bed slopes and for smaller UR values. The vegetal drag-Reynolds number model is extended for submerged flexible grass linings of differing heights and types. Similar values of the vegetative characteristic number k are evaluated as from previous studies yet for contrasting vegetation types. The vegetal drag coefficient value was found to be strongly correlated to the vegetation height, and follows a power law relationship. The exponent value was found to be independent of the vegetation characteristics.

Wilson, C. A. M. E.

2007-09-01

268

The classification, mapping and description of the vegetation of the Rooipoort Nature Reserve, Northern Cape, South Africa  

Directory of Open Access Journals (Sweden)

Full Text Available The need for a scientifically-based wildlife management plan and for more knowledge on vegetation led to an investigation into the plant ecology of the Rooipoort Nature Reserve. The main aim of this study was therefore to classify, describe and map the vegetation of the reserve. The floristic data were analysed according to the Braun-Blanquet procedure using the BBPC suite. The data analysis resulted in the identification of 15 communities that can be grouped into ten major community types. This resulted in five ecology-based management units, which could assist with the compilation of an ecologically sound management plan for the reserve in order to achieve sustainable utilisation of the natural resources. The Rooipoort Nature Reserve is one of the oldest and largest private nature reserves in South Africa and as such deserves to be conserved and protected. The riverine and pan vegetation communities are considered to be endangered and are in need of special conservation and protection.

Conservation implication: The results suggest five management units, which will assist in the compilation of an ecologically sound management plan for the RNR, in order to allow sustainable utilization of natural resources.

How to cite this article: Bezuidenhout, H., 2009, ‘The classification, mapping and description of the vegetation of the Rooipoort Nature Reserve, Northern Cape, South Africa’, Koedoe 51(1, Art. #695, 11 pages. DOI: 10.4102/koedoe.v51i1.695

Hugo Bezuidenhout

2009-01-01

269

Grains and Starchy Vegetables  

Science.gov (United States)

... A A Listen En Español Grains and Starchy Vegetables There is no end in sight to the ... 6 grams of sugar. Best Choices of Starchy Vegetables Starchy vegetables are great sources of vitamins, minerals ...

270

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

271

Discrepancies among ecological, household, and individual data on fruits and vegetables consumption in Brazil Discrepância entre dados ecológicos, domiciliares e individuais sobre o consumo de frutas e hortaliças no Brasil  

Directory of Open Access Journals (Sweden)

Full Text Available Information on fruits and vegetables consumption in Brazil in the three levels of dietary data was analyzed and compared. Data about national supply came from Food Balance Sheets compiled by the FAO; household availability information was obtained from the Brazilian National Household Budget Survey (HBS; and actual intake information came from a large individual dietary intake survey that was representative of the adult population of São Paulo city. All sources of information were collected between 2002 and 2003. A subset of the HBS, representative of São Paulo city, was used in our analysis in order to improve the quality of the comparison with actual intake data. The ratio of national supply to household availability of fruits and vegetables was 2.6 while the ratio of national supply to actual intake was 4.0. The discrepancy ratio in the comparison between household availability and actual intake was smaller, 1.6. While the use of supply and availability data has advantages, as lower cost, must be taken into account that these sources tend to overestimate actual intake of fruits and vegetables.Dados sobre o consumo de frutas e hortaliças no Brasil, em três níveis de informação, foram analisados e comparados. Dados sobre a oferta nacional foram obtidos em Folhas de Balanço de Alimentos da FAO; a disponibilidade domiciliar de frutas e hortaliças baseou-se em resultados da Pesquisa de Orçamentos Familiares (POF; informações sobre o consumo de frutas e hortaliças foram obtidas em um inquérito de consumo alimentar representativo da população adulta do Município de São Paulo. Todas as informações referem-se ao período entre 2002 e 2003. Uma subamostra dos domicílios da POF, representativa da cidade de São Paulo, foi utilizada a fim de melhorar a qualidade da comparação com dados de consumo de folhas e hortaliças. A razão entre a oferta nacional e a disponibilidade domiciliar de frutas e hortaliças foi de 2,6, enquanto a razão entre oferta nacional e o seu consumo foi de 4,0. A razão entre a disponibilidade domiciliar e o consumo foi de 1,6. Embora o uso de dados da oferta e disponibilidade de frutas e hortaliças apresente certas vantagens, como o menor custo, sua utilização deve levar em conta a tendência a superestimar o consumo de frutas e hortaliças.

Rafael Moreira Claro

2010-11-01

272

Discrepancies among ecological, household, and individual data on fruits and vegetables consumption in Brazil / Discrepância entre dados ecológicos, domiciliares e individuais sobre o consumo de frutas e hortaliças no Brasil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Dados sobre o consumo de frutas e hortaliças no Brasil, em três níveis de informação, foram analisados e comparados. Dados sobre a oferta nacional foram obtidos em Folhas de Balanço de Alimentos da FAO; a disponibilidade domiciliar de frutas e hortaliças baseou-se em resultados da Pesquisa de Orçame [...] ntos Familiares (POF); informações sobre o consumo de frutas e hortaliças foram obtidas em um inquérito de consumo alimentar representativo da população adulta do Município de São Paulo. Todas as informações referem-se ao período entre 2002 e 2003. Uma subamostra dos domicílios da POF, representativa da cidade de São Paulo, foi utilizada a fim de melhorar a qualidade da comparação com dados de consumo de folhas e hortaliças. A razão entre a oferta nacional e a disponibilidade domiciliar de frutas e hortaliças foi de 2,6, enquanto a razão entre oferta nacional e o seu consumo foi de 4,0. A razão entre a disponibilidade domiciliar e o consumo foi de 1,6. Embora o uso de dados da oferta e disponibilidade de frutas e hortaliças apresente certas vantagens, como o menor custo, sua utilização deve levar em conta a tendência a superestimar o consumo de frutas e hortaliças. Abstract in english Information on fruits and vegetables consumption in Brazil in the three levels of dietary data was analyzed and compared. Data about national supply came from Food Balance Sheets compiled by the FAO; household availability information was obtained from the Brazilian National Household Budget Survey [...] (HBS); and actual intake information came from a large individual dietary intake survey that was representative of the adult population of São Paulo city. All sources of information were collected between 2002 and 2003. A subset of the HBS, representative of São Paulo city, was used in our analysis in order to improve the quality of the comparison with actual intake data. The ratio of national supply to household availability of fruits and vegetables was 2.6 while the ratio of national supply to actual intake was 4.0. The discrepancy ratio in the comparison between household availability and actual intake was smaller, 1.6. While the use of supply and availability data has advantages, as lower cost, must be taken into account that these sources tend to overestimate actual intake of fruits and vegetables.

Claro, Rafael Moreira; Jaime, Patricia Constante; Lock, Karen; Fisberg, Regina Mara; Monteiro, Carlos Augusto.

273

Discrepancies among ecological, household, and individual data on fruits and vegetables consumption in Brazil / Discrepância entre dados ecológicos, domiciliares e individuais sobre o consumo de frutas e hortaliças no Brasil  

Scientific Electronic Library Online (English)

Full Text Available SciELO Public Health | Language: English Abstract in portuguese Dados sobre o consumo de frutas e hortaliças no Brasil, em três níveis de informação, foram analisados e comparados. Dados sobre a oferta nacional foram obtidos em Folhas de Balanço de Alimentos da FAO; a disponibilidade domiciliar de frutas e hortaliças baseou-se em resultados da Pesquisa de Orçame [...] ntos Familiares (POF); informações sobre o consumo de frutas e hortaliças foram obtidas em um inquérito de consumo alimentar representativo da população adulta do Município de São Paulo. Todas as informações referem-se ao período entre 2002 e 2003. Uma subamostra dos domicílios da POF, representativa da cidade de São Paulo, foi utilizada a fim de melhorar a qualidade da comparação com dados de consumo de folhas e hortaliças. A razão entre a oferta nacional e a disponibilidade domiciliar de frutas e hortaliças foi de 2,6, enquanto a razão entre oferta nacional e o seu consumo foi de 4,0. A razão entre a disponibilidade domiciliar e o consumo foi de 1,6. Embora o uso de dados da oferta e disponibilidade de frutas e hortaliças apresente certas vantagens, como o menor custo, sua utilização deve levar em conta a tendência a superestimar o consumo de frutas e hortaliças. Abstract in english Information on fruits and vegetables consumption in Brazil in the three levels of dietary data was analyzed and compared. Data about national supply came from Food Balance Sheets compiled by the FAO; household availability information was obtained from the Brazilian National Household Budget Survey [...] (HBS); and actual intake information came from a large individual dietary intake survey that was representative of the adult population of São Paulo city. All sources of information were collected between 2002 and 2003. A subset of the HBS, representative of São Paulo city, was used in our analysis in order to improve the quality of the comparison with actual intake data. The ratio of national supply to household availability of fruits and vegetables was 2.6 while the ratio of national supply to actual intake was 4.0. The discrepancy ratio in the comparison between household availability and actual intake was smaller, 1.6. While the use of supply and availability data has advantages, as lower cost, must be taken into account that these sources tend to overestimate actual intake of fruits and vegetables.

Claro, Rafael Moreira; Jaime, Patricia Constante; Lock, Karen; Fisberg, Regina Mara; Monteiro, Carlos Augusto.

274

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.

275

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  

Directory of Open Access Journals (Sweden)

Full Text Available 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.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

1998-04-01

276

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.

277

Arctic Vegetation Change and Feedbacks under Future Climate (Invited)  

Science.gov (United States)

Arctic surface air temperatures have risen at approximately twice the global rate, produce multiple climate feedbacks, e.g. via expansion of woody shrubs and trees into the tundra biome increasing surface net shortwave radiation due to reductions in albedo. To explore the feedbacks of future Arctic vegetation change on climate, we modeled vegetation type distribution across the circumpolar domain using machine-learning ecological niche models at moderately fine (4.5 x 4.5 km) spatial resolution. Vegetation was resolved into four classes of graminoids, four classes of shrubs, and two classes of tree cover. Comparison of observed and modeled classes under present climate revealed strong predictive performance. When simulating into the 2050s under scenarios of restricted tree dispersal and climate change, we found vegetation in 48-69% of our study area would shift to a different physiognomic class. Under an equilibrium scenario with unrestricted dispersal 57-84% of the area is predicted to shift to a different class. This latter scenario is supported by evidence of rapid shifts to larger growth-forms due to rapid colonization due to long-distance dispersal, expansion from refugia, and favorable conditions for establishment following disturbance like tundra fires and thermal erosion related to permafrost thaw. Distributions of lower-lying vegetation classes with sparse plant cover are predicted to contract in some places as larger shrubs and trees expand their ranges, but this outcome is mostly restricted to regions that do not have more northerly land masses to which vegetation could shift as trees and larger shrubs migrate from the south. We also estimated future changes in albedo, evapotranspiration and above-ground biomass, each of which would change substantially with our predicted widespread redistribution of Arctic vegetation. In terms of climate feedbacks, the predicted increases in ET were relatively small, and predicted maximum total increases in biomass (1.27 Pg) were roughly equivalent to the projected annual efflux of soil carbon to the atmosphere as a consequence of permafrost thaw over the coming century. In contrast, changes in Spring-Summer albedo (?) and net surface shortwave radiation (SN) indicate the significant extent to which vegetation change will influence climate. We estimate that ? will decrease by 2-6% under restricted tree dispersal and by 10-26% under equilibrium, corresponding to increases in SN of 1.07-3.11 W m-2 and 3.54-8.71 W m-2 under the same two scenarios. These changes are largely due to the snow masking effects of taller vegetation, indicating the projected vegetation changes would exacerbate currently amplified rates of regional warming. Our predictions thereby indicate that vegetation in the Arctic will affect climate primarily as a biophysical medium, whereas the carbon implications of Arctic change are largely those that influence permafrost and associated soil carbon stocks. As with thawing permafrost, vegetation distribution shifts will result in an overall positive feedback to climate that is likely to cause greater warming than has previously been predicted.

Goetz, S. J.; Loranty, M. M.; Beck, P.; Phillips, S.; Damoulas, T.; Pearson, R. G.

2013-12-01

278

Ecology and Biogeography (some ideas ???????? ? ???????????? (????????? ???????????  

Directory of Open Access Journals (Sweden)

Full Text Available The article discusses methods and approaches to identify and assess the communication of environmental factors and variability of totals and the character of flora, fauna, vegetation and animal population by the given environment gradients and search of trends inherent in heterogeneity of communities. Attention is paid to the feasibility assessment of connections not only with single factors, but their inseparable combinations - natural and man-made modes. The differences are shown between targeted and value ??approaches in the researches and connected with this either their greater geographical or ecological bias.??????????? ?????? ? ??????? ? ????????? ? ?????? ????? ???????? ????? ? ???????????? ????????? ??????????? ? ?????? ?????, ?????, ?????????????? ? ????????? ????????? ?? ???????? ?????????? ????? ? ?????? ??????? ??????????? ?????????????? ?????????. ???????? ???????? ?? ???????????????? ?????? ????? ?? ?????? ? ?????????? ?????????, ?? ?? ????????????? ??????????? – ????????-?????????????? ????????. ???????? ???????? ??????? ? ?????????? ?????????????? ? ????????????? ? ????????? ? ???? ?? ??????? «??????????????» ??? «?????????????».

Ravkin Yury Solomonovich

2013-10-01

279

Ecologism in Interior Design  

Directory of Open Access Journals (Sweden)

Full Text Available With the progress of our mankind, great changes have taken place in economy as well as our society, so have the natural environment and ecological system in which we live. Nowadays, we are faced with decreasing natural environment, forest, species, clean water, air and cultivable land. In addition, some urgent issues such as global warming, exhausted energy and widespread rubbish force us to reflect on our future life style. In this situation, interior designers are expected to introduce ecological ideas into their design to push it to a higher and advanced level, which will consequently promote the transformation of the employment of resources in architecture from the consumptive type to the recycled one.

Ruizhou Liu

2009-02-01

280

Analysis of Vegetation Behavior in a North African Semi-Arid Region, Using SPOT-VEGETATION NDVI Data  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The analysis of vegetation dynamics is essential in semi-arid regions, in particular because of the frequent occurrence of long periods of drought. In this paper, multi-temporal series of the Normalized Difference of Vegetation Index (NDVI), derived from SPOT-VEGETATION satellite data between September 1998 and June 2010, were used to analyze the vegetation dynamics over the semi-arid central region of Tunisia. A study of the persistence of three types of vegetation (pastures, annual agricult...

Rim Amri; Mehrez Zribi; Zohra Lili-Chabaane; Benoit Duchemin; Claire Gruhier; Abdelghani Chehbouni

2011-01-01

 
 
 
 
281

Ecological stability of landscape - ecological infrastructure - ecological management  

International Nuclear Information System (INIS)

The Field Workshop 'Ecological Stability of Landscape - Ecological Infrastructure - Ecological Management' was held within a State Environmental Programme financed by the Federal Committee for the Environment. The objectives of the workshop were to present Czech and Slovak approaches to the ecological stability of the landscape by means of examples of some case studies in the field, and to exchange ideas, theoretical knowledge and practical experience on implementing the concept of ecological infrastructure in landscape management. Out of 19 papers contained in the proceedings, 3 items were inputted to the INIS system. (Z.S.)

1992-06-15

282

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

2000-06-13

283

Leukemia Ecology: Ecological Prophylaxis of Leukemia.  

Science.gov (United States)

Contents: Etiopathogenesis of leukemia; Ecological leukemogenic factors; Epidemiology of leukemias; Geochemical environment in relationship to health and disease; Leukemia risk factor bank; Perspectives of leukemia prophylaxis by ecological and dietary me...

J. Aleksandrowica A. B. Skotnicki

1982-01-01

284

The Role of plant type and salinity in the selection for the denitrifying community structure in the rhizosphere of wetland vegetation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Coastal wetlands, as transient links from terrestrial to marine environments, are important for nitrogen removal by denitrification. Denitrification strongly depends on both the presence of emergent plants and the denitrifier communities selected by different plant species. In this study, the effects of vegetation and habitat heterogeneity on the community of denitrifying bacteria were investigated in nine coastal wetlands in two preserved areas of Spain. Sampling locations were selected to c...

Ban?eras Vives, Llui?s; Ruiz Rueda, Olaya; Lo?pez I Flores, Roci?o; Quintana Pou, Xavier; Hallin, Sara

2012-01-01

285

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2004-01-01

286

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

1996-01-01

287

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

288

Estratificacao de Areas Desflorestadas Por Tipos de Vegetacao DA Amazonia, Utilizando Sistema de Informacoes Geograficas: Estudo de Caso NA Folha SB20 Purus (Stratification of Deforested Areas by Vegetation Types in Amazonia, Using Geographic Information Systems: Study of Case at SB20 Purus MAP).  

Science.gov (United States)

A methodology to stratify deforested areas by Amazonia vegetation types, using geoprocessing techniques was tested for SB20 Purus map. The approach concerns the integration of different scales and projections data, so two datasets were considered: defores...

J. D. Deoliveira

1993-01-01

289

The Circumpolar Arctic vegetation map  

Science.gov (United States)

Question: What are the major vegetation units in the Arctic, what is their composition, and how are they distributed among major bioclimate subzones and countries? Location: The Arctic tundra region, north of the tree line. Methods: A photo-interpretive approach was used to delineate the vegetation onto an Advanced Very High Resolution Radiometer (AVHRR) base image. Mapping experts within nine Arctic regions prepared draft maps using geographic information technology (ArcInfo) of their portion of the Arctic, and these were later synthesized to make the final map. Area analysis of the map was done according to bioclimate subzones, and country. The integrated mapping procedures resulted in other maps of vegetation, topography, soils, landscapes, lake cover, substrate pH, and above-ground biomass. Results: The final map was published at 1:7 500 000 scale map. Within the Arctic (total area = 7.11 x 106 km 2), about 5.05 ?? 106 km2 is vegetated. The remainder is ice covered. The map legend generally portrays the zonal vegetation within each map polygon. About 26% of the vegetated area is erect shrublands, 18% peaty graminoid tundras, 13% mountain complexes, 12% barrens, 11% mineral graminoid tundras, 11% prostrate-shrub tundras, and 7% wetlands. Canada has by far the most terrain in the High Arctic mostly associated with abundant barren types and prostrate dwarf-shrub tundra, whereas Russia has the largest area in the Low Arctic, predominantly low-shrub tundra. Conclusions: The CAVM is the first vegetation map of an entire global biome at a comparable resolution. The consistent treatment of the vegetation across the circumpolar Arctic, abundant ancillary material, and digital database should promote the application to numerous land-use, and climate-change applications and will make updating the map relatively easy. ?? IAVS; Opulus Press.

Walker, D. A.; Reynolds, M. K.; Daniels, F. J. A.; Einarsson, E.; Elvebakk, A.; Gould, W. A.; Katenin, A. E.; Kholod, S. S.; Markon, C. J.; Melnikov, E. S.; Moskalenko, N. G.; Talbot, S. S.; Yurtsev, B. A.; Bliss, L. C.; Edlund, S. A.; Zoltai, S. C.; Wilhelm, M.; Bay, C.; Gudjonsson, G.; Moskalenko, N. G.; Ananjeva, G. V.; Drozdov, D. S.; Konchenko, L. A.; Korostelev, Y. V.; Melnikov, E. S.; Ponomareva, O. E.; Matveyeva, N. V.; Safranova, I. N.; Shelkunova, R.; Polezhaev, A. N.; Johansen, B. E.; Maier, H. A.; Murray, D. F.; Fleming, M. D.; Trahan, N. G.; Charron, T. M.; Lauritzen, S. M.; Vairin, B. A.

2005-01-01

290

[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

291

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

292

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.

293

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

294

Sound Ecologies  

Directory of Open Access Journals (Sweden)

Full Text Available Discussions about what constitutes ‘the rural’ invariably focus on notions of spatial location – of inhabiting spaces apart from that of the metropolitan. Deeply embedded in our images of what it means to be Australian, nonetheless our intellectual framing of ‘the rural’ as something outback and beyond has significant implications for our relations with these spaces. The relatively recent phenomenon of sea- and tree-changes has struck many unawares, and not simply because a good latté is so hard to find. Although a frivolous remark, such an apparent lack does shift our focus to a bodily scale of the rural; how is rural place re/made through our experiences of it? This article originates out of on-going research that explores the practice of listening and sound and the ways in which the body can draw attention to the intuitive, emotional, and psychoanalytical processes of subjectivity and place-making. Drawing on Nigel Thrift’s concept of an ecology of place, I suggest that contemporary heightened concerns with regards to loss and lack in rural Australia has led to a nascent emotional economy – one in which individual and intimate connections to the rural require a rethinking of how we live community and belonging. In such a terrain, what does it mean to be rural?

Michelle Duffy

2010-02-01

295

Sound Ecologies  

Directory of Open Access Journals (Sweden)

Full Text Available Discussions about what constitutes ‘the rural’ invariably focus on notions of spatial location – of inhabiting spaces apart from that of the metropolitan. Deeply embedded in our images of what it means to be Australian, nonetheless our intellectual framing of ‘the rural’ as something outback and beyond has significant implications for our relations with these spaces. The relatively recent phenomenon of sea- and tree-changes has struck many unawares, and not simply because a good latté is so hard to find. Although a frivolous remark, such an apparent lack does shift our focus to a bodily scale of the rural; how is rural place re/made through our experiences of it? This article originates out of on-going research that explores the practice of listening and sound and the ways in which the body can draw attention to the intuitive, emotional, and psychoanalytical processes of subjectivity and place-making. Drawing on Nigel Thrift’s concept of an ecology of place, I suggest that contemporary heightened concerns with regards to loss and lack in rural Australia has led to a nascent emotional economy – one in which individual and intimate connections to the rural require a rethinking of how we live community and belonging. In such a terrain, what does it mean to be rural?

Michelle Duffy

2010-03-01

296

Sound ecologies  

Directory of Open Access Journals (Sweden)

Full Text Available Discussions about what constitutes ‘the rural’ invariably focus on notions of spatial location – of inhabiting spaces apart from that of the metropolitan. Deeply embedded in our images of what it means to be Australian, nonetheless our intellectual framing of ‘the rural’ as something outback and beyond has significant implications for our relations with these spaces. The relatively recent phenomenon of sea- and tree-changes has struck many unawares, and not simply because a good latté is so hard to find. Although a frivolous remark, such an apparent lack does shift our focus to a bodily scale of the rural; how is rural place re/made through our experiences of it? This article originates out of on-going research that explores the practice of listening and sound and the ways in which the body can draw attention to the intuitive, emotional, and psychoanalytical processes of subjectivity and place-making. Drawing on Nigel Thrift’s concept of an ecology of place, I suggest that contemporary heightened concerns with regards to loss and lack in rural Australia has led to a nascent emotional economy – one in which individual and intimate connections to the rural require a rethinking of how we live community and belonging. In such a terrain, what does it mean to be rural?

Duffy, Michelle

2010-01-01

297

Ecologia da paisagem: mapeamento da vegetação da Reserva Biológica da Serra do Japi, Jundiaí, SP, Brasil Landscape ecology: vegetation map of the Reserva Biológica da Serra do Japi, Jundiaí, SP, Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available Foi realizado o mapeamento da vegetação da Reserva Biológica (REBIO Municipal da Serra do Japi, Jundiaí, SP, por meio de fotointerpretação analógica, em escala 1:30.000. O mapa foi digitalizado e transferido para computador pelo sistema de informação geográfica (Idrisi e posteriormente para o programa Corel Draw. Foram identificadas, mapeadas e descritas oito unidades de paisagem (UP sendo três antrópicas (solo exposto, campo antrópico e reflorestamento homogêneo e cinco naturais (floresta estacional semidecidual montana dossel uniforme - microfanerófitos; floresta estacional semidecidual montana dossel uniforme - mesofanerófitos; floresta estacional semidecidual montana dossel emergente; floresta estacional semidecidual aluvial dossel emergente e refúgio montano arbustivo. As unidades naturais somaram 98,46% do total dos 2.071,20 ha da área, indicando que a Reserva vem cumprindo seu papel na preservação do ecossistema em questão. No entanto, como algumas unidades não tem expressiva representatividade na área, e como existe grande extensão de floresta no entorno da Reserva, sugere-se a ampliação e a transformação da mesma em uma unidade que contemple inclusive a visitação pública como forma de auxiliar no processo de conservação. Sugere-se que a área seja transformada em parque estadual, cujo nome poderia ser Parque Estadual da Serra do Japi.It was realized the vegetation map of the Reserva Biológica Municipal da Serra do Japi, at Jundiaí, São Paulo State, by analogical photointerpretation, on the scale 1:30.000. The map was digitized and changed to computer by the geographical information system - Idrisi, and then to the Corel Draw program. Eight landscape units, three anthropic - bare earth, anthropic prairie, homogeneous reforestation, and five natural units - mountainseasonal semideciduous forest with uniform canopy and microphanerophyts, mountain seasonal semideciduous forest with uniform canopy and mesophanerophyts, mountain seasonal semideciduous forest with emergent canopy, alluvial seasonal semideciduous forest with emergent canopy, and shrubby mountain refuges, were identified, mapped, and described. The natural units added 98,46% of the total area, showing that the Reserve is carrying out this role in the ecosystem conservation, but as some units are not significantly represented, and since of the large forest extension outside Reserve, it was offered the suggestion that the Reserve with the enlarged area be changed to another conservation unit-category and that contemplate the public visitation, to help in the conservation process. The conservation unit more appropriated is a Park, and could be denominated Parque Estadual da Serra do Japi.

Eliana Cardoso-Leite

2005-06-01

298

Elemental sources, cycling, and ecological availability in rivers in carbonate terrains: An interdisciplinary perspective  

Science.gov (United States)

Multiple, coupled physical, chemical and biologic processes control the sources and cycling of solutes in streams; however, the relative magnitude and temporal variability of individual processes can be difficult to differentiate in large rivers. Understanding the timing and magnitude of these processes is critical to preserving the water quality and ecological health of stream systems and predicting their responses to environmental change. The large springs of north Florida are characterized by stable chemical composition and discharge, high clarity and naturally low metal concentrations. As a result, spring-fed rivers provide model systems to study the interactions between the hydrologic, geochemical and ecological processes which control the availability and cycling of solutes within streams and the feedbacks between these solute dynamics and submerged vegetation. We combined high-frequency river and synoptic pore-water sampling, with measurements of submerged vegetation stoichiometry, and long-term records of river and pore-water hydrology in the Ichetucknee River, FL to investigate how diffuse groundwater discharge and in-stream diel (24-hr) cycling mediate the environmental availability of solutes and the composition and function of aquatic vegetation. Diffusion and diffuse groundwater flow from the anoxic river-bottom sediments provide a source of Fe, Mn, P, Ca and Cl to the aquatic ecosystem distinct from other spring water inputs. In-stream solute concentrations of Ca, Mn, Ba, Cr, V, Fe, U, and Sr cycle at diel time scales as a result of a number of overlapping inorganic processes indirectly controlled by solar radiation and the primary production of submerged vegetation. Plant metabolism also directly contributes to the diel removal of trace metals via assimilatory uptake, although the exact timing of assimilation relative to the other inorganic controls remains uncertain. Tissue stoichiometry varies between vegetation types (submerged macrophytes generally enriched in major elements and depleted in trace elements relative to benthic algae), and between sampling sites (in correlation with changes in ambient water chemistry for select elements, including Mn, Cr, U, and Sr). Since diffuse hyporheic sources and in-river cycling mediate the availability of nutrients to the aquatic ecosystem, these processes may affect the productivity and relative abundance of algae and submerged macrophytes. Conversely, changes in species abundance could lead to corresponding changes in the magnitude of assimilatory uptake and thus control in-stream diel variations. These results illustrate the reciprocal interactions between solute dynamics in streams and the elemental requirements of submerged aquatic vegetation, and highlight the significance of the hyporheic zone as an ecologically important source of solutes to rivers with otherwise homogenous source chemistry.

Kurz, M. J.; Martin, J. B.; Cohen, M. J.; de Montety, V.; Nifong, R. L.

2013-12-01

299

High herbivore density associated with vegetation diversity in interglacial ecosystems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The impact of large herbivores on ecosystems before modern human activities is an open question in ecology and conservation. For Europe, the controversial wood-pasture hypothesis posits that grazing by wild large herbivores supported a dynamic mosaic of vegetation structures at the landscape scale under temperate conditions before agriculture. The contrasting position suggests that European temperate vegetation was primarily closed forest with relatively small open areas, at most impacted loc...

2014-01-01

300

Vegetative reproduction capacities of floodplain willows--cutting response to competition and biomass loss.  

Science.gov (United States)

While several studies on regeneration in Salicaceae have focused on seedling recruitment, little is known about factors controlling their vegetative reproduction. In two greenhouse experiments, we studied the response of floodplain willows (Salix fragilis, S. viminalis, S. triandra) to competition with Poa trivialis, and to shoot and root removal when planted as vegetative cuttings. In the first experiment, growth performance variables were analysed in relation to full competition, shoot competition, root competition and control, taking into account two different water levels. After 9 weeks, shoots were removed and the resprouting capacity of the bare cuttings was recorded. In the second experiment, the cutting performance of the three floodplain and an additional two fen willow species (S. cinerea, S. aurita) was compared when grown in three different soil compositions and with two different water levels. After 9 weeks, shoot and root biomass was removed and the bare cuttings were replanted to test their ability to resprout. Cutting performance and secondary resprouting were negatively affected by full and shoot competition while root competition had no or weak effects. The floodplain species performed better than the fen species in all soil types and water levels. Secondary resprouting capacity was also higher in the floodplain species, which showed an additional strong positive response to the previous waterlogging treatment. The results contribute to understanding of the vegetative regeneration ecology of floodplain willows, and suggest that the use of vegetative plantings in restoration plantings could be an effective strategy for recovering floodplain forests. PMID:21972956

Radtke, A; Mosner, E; Leyer, I

2012-03-01

 
 
 
 
301

Vegetation Greenness in Northeastern Brazil and Its Relation to ENSO Warm Events  

Directory of Open Access Journals (Sweden)

Full Text Available The spatio-temporal variability of trends in vegetation greenness in dryland areas is a well-documented phenomenon in remote sensing studies at global to regional scales. The underlying causes differ, however, and are often not well understood. Here, we analyzed the trends in vegetation greenness for a semi-arid area in northeastern Brazil (NEB and examined the relationships between those dynamics and climate anomalies, namely the El Nino Southern Oscillation (ENSO for the period 1982 to 2010, based on annual Normalized Difference Vegetation Index (NDVI values from the latest version of the Global Inventory Modeling and Mapping Studies (GIMMS NDVI dataset (NDVI3g dataset. Against the ample assumption of ecological and socio-economic research, the results of our inter-annual trend analysis of NDVI and precipitation indicate large areas of significant greening in the observation period. The spatial extent and strength of greening is a function of the prevalent land-cover type or biome in the study area. The regression analysis of ENSO indicators and NDVI anomalies reveals a close relation of ENSO warm events and periods of reduced vegetation greenness, with a temporal lag of 12 months. The spatial patterns of this relation vary in space and time. Thus, not every ENSO warm event is reflected in negative NDVI anomalies. Xeric shrublands (Caatinga are more sensitive to ENSO teleconnections than other biomes in the study area.

Stefan Erasmi

2014-04-01

302

The feasibility of ecological taxation  

International Nuclear Information System (INIS)

The feasibility of ecological taxation in general and for the Netherlands in specific was analyzed within the context of one of the NRP research projects. The analysis shows that the feasibility of ecological taxes is generally determined by the tax design, the taxing authority by which these taxes are imposed and by the constitutional, institutional and fiscal structures into which they are embedded. In order to be feasible, the analysis shows that ecologically relevant taxes have to be imposed by a taxing authority which is clearly related to relevant ecological circumstances. Since normal taxing authorities tend to be political units which most of the times do not fit this description, institutional and constitutional changes are necessary to introduce and impose (additional) feasible types of ecological taxes in practice. Within the context of the Netherlands, the analysis shows that the currently changing intergovernmental and financial relationships in this country provide important starting points for municipalities, water authorities and provinces to introduce feasible types of such taxes. 225 refs

1995-01-01

303

The feasibility of ecological taxation  

Energy Technology Data Exchange (ETDEWEB)

The feasibility of ecological taxation in general and for the Netherlands in specific was analyzed within the context of one of the NRP research projects. The analysis shows that the feasibility of ecological taxes is generally determined by the tax design, the taxing authority by which these taxes are imposed and by the constitutional, institutional and fiscal structures into which they are embedded. In order to be feasible, the analysis shows that ecologically relevant taxes have to be imposed by a taxing authority which is clearly related to relevant ecological circumstances. Since normal taxing authorities tend to be political units which most of the times do not fit this description, institutional and constitutional changes are necessary to introduce and impose (additional) feasible types of ecological taxes in practice. Within the context of the Netherlands, the analysis shows that the currently changing intergovernmental and financial relationships in this country provide important starting points for municipalities, water authorities and provinces to introduce feasible types of such taxes. 225 refs.

Paulus, A.T.G. [University of Limburg, Faculty of Economics and Business Administration, Maastricht (Netherlands)

1995-12-31

304

Plant species diversity in the ecological species groups in the Kandelat Forest Park, Guilan, North of Iran  

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Full Text Available Pourbabaei H, Haghgooy T. 2012. Plant species diversity in the ecological species groups in the Kandelat Forest Park, Guilan, North of Iran. Biodiversitas 13: 7-12. Forest vegetation indicates conditions and productivity potential of forest habitat, because it reflects the interaction of climate, soil and topography. The aim of this research was to study the relationship between vegetation and topography factors. In order to do this research, type, number and percentage cover of trees, shrubs (sample plot with 1000 m2 area and type and percentage cover of herbaceous species (sample plot with 64 m2 area investigated and recorded. The coverage percent of species were estimated on the basis of Domin scale. Vegetation classified using Two-Way Indicator Species Analysis (TWINSPAN. The results revealed that there were 6 ecosystem units (ecological groups in the region. The comparison of diversity indices and topographic factors between groups were performed with ANOVA test. Results also indicated that there were significant differences between groups in terms of biodiversity indices and topographic factors. The formation of a particular group is affected by a combination of environment variables. The aspect was the most important variable of topographic factors in this study.

HASSAN POURBABAEI

2012-01-01

305

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

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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.

Jacques Hubert Charles Delabie

2013-07-01

306

Ecological, biological balances and conservation  

International Nuclear Information System (INIS)

The scientific work within the activity ''ecological/biological balances and conservation'' is summarised in this report. The aims of the activity during its existence between 1992 and 1994 have been to: (i) arrange a workshop and publish the presentations on the environmental aspects of energy forest cultivations, (ii) perform joint scientific work together with the activity group on ''biological disposal of wastewaters and sludges'', that is closely related to environmental problems, and (iii) produce ecological guidelines concerning energy forestry, suitable for advisers and farmers dealing with bioenergy problems. The most important results from the workshop were the environmental benefits from energy forestry when compared with intensive agriculture and forestry. Energy forestry has positive influence on the carbon balances, nutrient recycling, and soil sustainability. The effects are also positive on the natural flora and fauna, which in most cases are enriched when compared with agricultural crops. From the joint efforts of the two activities the main result was a study tour, conference and workshop, concentrating on biological purification systems. The most promising system seems to be the vegetation filters of short rotation coppice. The report on ecological guidelines contains a number of ideas and recommendations for establishment, management, and harvesting of energy forests in an environmentally acceptable way. It also gives advice on how to locate the stands to minimise the risk of nutrient leakage from arable land. (Author)

1995-03-23

307

Assessing ecological land use and water demand of river systems: a case study in Luanhe River, North China  

Directory of Open Access Journals (Sweden)

Full Text Available Economic and social development has greatly increased ecological water demand and modified land use of river systems worldwide, causing overall degradation of many of these systems. In this study, theoretical and technical frameworks for regionalization on the eco-environmental function of river systems are formulated and applied to the Luanhe River system. Based on its eco-environmental functions, this river can be regionalized into four types of first-class functional areas: ecological preservation areas, habitat restoration areas, ecological buffer areas and development and utilization areas. Considering the overall eco-environmental functions, we assessed the ecological land use of the Luanhe River system. The total area of basic ecological land use is 876.98 km2; the restrictive ecological land use is 1745.52 km2; ecological land use of the river system returned from farmland is 284.25 km2; and that returned from construction land is 17.35 km2. The average minimum ecological flow of mainstreams in upper and middle reaches of the Luanhe River is 4.896 m3 s?1 based on the habitat method. And the recommended minimum and suitable annual ecological water demand of channels in the lower reaches are 391 million m3 and 819.5 million m3, respectively. The evaporation and seepage consumption and vegetation consumption in riparian zones of the Luanhe River system are approximately 132.6 million m3 and 145.3 million m3 per year, respectively. Our results suggest that is crucial to regulate the instream ecological water use of the Luanhe River's mainstream starting from the Panjiakou-Daheiting Reservoir system. We recommend accelerating ecological land-use planning and strengthening the regulation of ecological water use on this river system focusing on important lower reaches under the condition of competitive water demand.

D. H. Yan

2012-08-01

308

PROPOSAL OF A SYNTHETIC IND ICATOR TO CONTROL ECOLOGICAL DYNAMICS AT AN ECOLOGICAL MOSAIC SCALE  

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Full Text Available The problem to control transformations of an ecological mosaic is becoming more and more important. These transformations occur according to processes linked with thresholds of metastability, which correspond to a passage from a metastable equilibrium to another. Trying to evaluate the metastability of a certain ecological mosaic, it is necessary to identify the levels of replacement and to measure the metastability of each element, in order to consider their complementarity. It is possible to measure the capacity of an ecological mosaic, formed by a vegetational mosaic, defining a synthetic quantity, named biological territorial capacity, or Btc. It ranks landscape’s elements, giving high values to high-resistance ecosystems. Therefore, it is possible to use the Btc as a synthetic indicator of the metastability of an ecological mosaic. Some examples of application regard Gallarate heath-land (local scale and Lathium, Lombardy and Sicily (regional scales.

E. GIGLIO

1999-01-01

309

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

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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

310

Assessment of the environmental effects of mining using SPOT-Vegetation NDVI  

Science.gov (United States)

Within the ImpactMin project, funded by the Framework Programme 7 of the European Commission, new methods for the environmental impact monitoring of mining operations are being developed. The objective of this study is to analyze the impact of mining on soil properties through assessment of the vegetation status using time series analysis of low resolution Normalized Difference Vegetation Index (NDVI) images derived from SPOT-Vegetation. The study focuses on the surroundings of mining areas in the Orenburg region in the Russian Urals. Karabash has been a centre for mining and metal production for well over 3000 years, and environmental impact of (historical) mining in the area is extremely severe. The area was characterized as an 'ecological disaster zone', based on chemical analysis of soil samples in the area [1]. The mining activities were intensified in the early to mid-20th century, but the old smelter was modernized in the 1990s. A time series of 10-daily NDVI images from SPOT-Vegetation (S10 April/1998-December/2010 at 1km2 resolution, http://www.vgt.vito.be/) is analyzed. Different land cover types clearly show different phenology. To remove seasonal vegetation changes and thus to facilitate the interpretation through the historical record, a Standardized Difference Vegetation Index (SDVI) was calculated for each pixel and for each record of the time series. The first results of trend analyses indicate a strong recovery of open forests in the Karabash region in the last decade. To what extent this can be related to reduced mining impact or climate factors, still needs to be assessed. Further research will also focus on the spatial heterogeneity of phenological parameters, in relation to distance to and wind direction of the smelters and soil properties. [1] V. Nestersnko, "Urban associations of elements- environmental pollutants in Karabash city (Chelyabinsk oblast) as a reflection of ore-chemical descriptions of mineral raw material", Proceedings of the Chelyabinsk Scientific Center, vol. 3, pp. 58-62, 2006.

Tote, C.; Swinnen, E.; Goossens, M.; Reusen, I.; Delalieux, S.

2012-04-01

311

Variación de la estructura y composición de comunidades de árboles y arbustos entre tipos de vegetación en la Cuenca de Cuitzeo, Michoacán / Structural and composition variation of tree and shrub communities among vegetation types in the Cuitzeo Basin, Michoacán, Mexico  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Se analizó la variación estructural de comunidades de árboles y arbustos presentes en diferentes tipos de vegetación (matorral subtropical, bosque de encino, bosque mixto, bosque de pino y bosque de oyamel) a través de gradientes de altitud y profundidad del suelo en la Cuenca de Cuitzeo, Michoacán. [...] La cuenca cubre 4,000 km² y un ámbito altitudinal de 1,700 a 3,420 m s.n.m. En toda la cuenca se muestrearon 50 sitios de 1,000 m² cada uno, se registró un total de 4,941 plantas con diámetro a la altura del pecho ? 1 cm, que representaron 164 especies, 88 géneros y 47 familias. Las familias con más especies fueron Asteraceae (30; 18.4% del total de especies) y Fagaceae (16; 9.8%). Por arriba de los 2,500 m s.n.m. se encontraron los bosques de pino, oyamel y mixto (pino-encino); por debajo de 2,300 m s.n.m. se encontraron el bosque de encino y el matorral subtropical. La densidad de plantas fue semejante entre los tipos de vegetación, pero diferentes indicadores de la biomasa aumentaron con la altitud y la profundidad del suelo. El matorral subtropical y el bosque mixto fueron los más diversos en especies, mientras que el bosque de coníferas fue el menos diverso. Existió un elevado recambio de especies dentro y entre los tipos de vegetación (índice de similitud de Bray-Curtis, ámbito: 5.4-25.4%). La composición de especies varió notablemente asociada con la altitud y la profundidad del suelo. Se ofrecen lineamientos para la conservación del importante complejo vegetal presente en la Cuenca de Cuitzeo. Abstract in english This work analyzed the structural variation of tree and shrub communities present in different vegetation types (subtropical scrub, oak forest, mixed forest, pine and fir forest) across altitudinal gradients and soil depth at the Cuitzeo Basin, Michoacán. The basin covers 4,000 km² and altitudinal r [...] ange of 1,700 to 3,420 m a.s.l. In the entire basin we sampled 50 sites 1,000 m² each, recording a total of 4,941 plants with a diameter at breast height ? 1 cm, representing 164 species, 88 genera and 47 families. Families with more species were Asteraceae (30, 18.4% of total species) and Fagaceae (16, 9.8%). Above 2,500 m a.s.l. were found pine, fir and mixed (pine-oak) forests; below 2,300 m a.s.l. were found the oak forest and subtropical scrub. Plant density was similar among vegetation types but different indicators of community biomass increased with altitude and soil depth. The subtropical scrub and mixed forest were the most diverse in species and coniferous forest the less diverse. There was a high turnover of species within and among vegetation types (index of Bray-Curtis similarity, range: 5.4-25.4%). The vegetation composition varied significantly associated with altitude and soil depth. We offer some guidelines for the conservation of the important vegetation complex present in the Cuitzeo Basin.

Susana, Maza-Villalobos; Franceli, Macedo-Santana; Jorge, Rodríguez-Velázquez; Ken, Oyama; Miguel, Martínez-Ramos.

312

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.)

1984-01-01

313

Integrated Evaluation of Ecological Sustainability of a Mining Area in the Western Region of China  

Directory of Open Access Journals (Sweden)

Full Text Available The ecological environment is extremely fragile in the western region of China, where the largest coal mining company in China is located. After mining, subsidence and massive loss of water resources occur in many areas. Plant mortality caused by lack of water, has made the fragile ecological environment deteriorate much more rapidly after 1986. Therefore, an investigation of eco-environmental sustainability in the mining area is imperative. Based on Remote Sensing (RS and GIS, two typical mines were selected as study areas. Four types of spatial information (desertification, land use structure, water and soil erosion, and vegetation for the ecological environment were extracted from remote sensing imagery for 5 periods (August 2, 1986, August 29, 1990, July 26, 1995, July 31, 2000, and July 24, 2006. The spatial information was used to construct an evaluation index system. Based on a grid of environmental data, the environmental index was used to develop and design an integrated evaluation model for evaluating sustainability of the ecological environment in the mining area. Four classes of ecological sustainability were identified by the model. The analyses identified variability in the environmental sustainability. The changes in loess areas were much greater than in sandy areas because subsidence in loess areas was more serious than that in sandy areas. Because most cropland occurs in loess areas, and the ecological environment of loess regions is extremely sensitive and vulnerable to desertification, negative effects of mining are a serious concern. Therefore, evaluation of the environmental sensitivity and sustainability of the mining area is indispensable. The results of this evaluation corresponded quite well with the actual environmental conditions, demonstrating that this model is scientifically sound and objective. Application of this model to other mines and mining regions within China can be used to evaluate potential impacts in environmentally sensitive areas.

Yufen Hao

2013-04-01

314

NATURAL VEGETATION OF BIHAR  

Directory of Open Access Journals (Sweden)

Full Text Available 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.

R.N. Pandey

2014-04-01

315

dealing with vegetation-3  

Dealing with vegetation on historic masonry monuments Protecting historic monuments guidance booklet Contents Problems caused by Vegetation 1 Natural Heritage Interests 1 Ivy 2 Steps for Treating Ivy 3 Herbicide 5 ...

316

The Ecology of Recently-deglaciated Terrain  

Science.gov (United States)

This book provides the first comprehensive review of the available information on the ecology of recently-deglaciated terrain and critically evaluates the methodology currently employed in such studies. The theme developed is that the ecology of these regions can only be fully understood by giving due consideration to the role and interaction of both physical and biological processes in the development of the landscape. By adopting this geoecological approach, the spatial variation and dynamics of vegetation and soils is considered in relation to other aspects of the landscape such as topographic variation, climate, and geomorphic processes. A geoecological model is thus outlined that provides both a framework for interpreting the varied ecological nature of glacier forelands found throughout the world, and also an agenda for future research.

Matthews, John A.

1992-05-01

317

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

318

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.

Ricetti, Janael; Bonaldo, Alexandre B..

319

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

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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

320

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

Science.gov (United States)

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.

Arieira, J.; Karssenberg, D.; de Jong, S. M.; Addink, E. A.; Couto, E. G.; Nunes da Cunha, C.; Skøien, J. O.

2010-09-01

 
 
 
 
321

Effects of Flow and Vegetation States on River Roughness Coefficients  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation roughness coefficients are the main parameters used to determine river flow characteristics and are known to depend on the flow condition (depth and velocity) as well as vegetation condition (type and density). Flume experiments were conducted to investigate the variation of roughness coefficients with flow conditions and vegetation density for submerged vegetation in river bed, banks and flood plains. Artificial plastic plants, for a length of 0.2 m, were laid on the floor of a 14...

Ebrahimi, N. G.; Fathi-moghadam, M.; Kashefipour, S. M.; Saneie, M.; Ebrahimi, K.

2008-01-01

322

A new world natural vegetation map for global change studies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We developed a new world natural vegetation map at 1 degree horizontal resolution for use in global climate models. We used the Dorman and Sellers vegetation classification with inclusion of a new biome: tropical seasonal forest, which refers to both deciduous and semi-deciduous tropical forests. SSiB biogeophysical parameters values for this new biome type are presented. Under this new vegetation classification we obtained a consensus map between two global natural vegetation maps widely use...

Lapola, David M.; Oyama, Marcos D.; Nobre, Carlos A.; Gilvan Sampaio

2008-01-01

323

Crude vegetable oil refining service (under development) - Environmental Product Declarations - Product Category Rules  

... Crude vegetable oil refining service (under development) - Environmental Product Declarations - Product Category Rules Crude vegetable oil refining service (...Forum Search Comment this PCR Post Using EPDs PCR Search Crude vegetable oil refining service (under development) Search Pcr Crude vegetable oil ... Please note that this PCR only refers to crude vegetable oil refining services for the following types of oil: crude soybean,...rapeseed, sunflower seed, palm, palm kernel and coconut oil.& nbsp Detailed information Name: Crude vegetable oil refining service (under development) CPC ...

324

Ecological and Human Community Resilience in Response to Natural Disasters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ecological resilience, adaptive cycles, and panarchy are all concepts that have been developed to explain abrupt and often surprising changes in complex socio-ecological systems that are prone to disturbances. These types of changes involve qualitative and quantitative alterations in systems' structures and processes. This paper uses the concepts of ecological resilience, adaptive cycles, and panarchies to compare ecological and human community systems. At least five important findings e...

Lance Gunderson

2010-01-01

325

Index of Alien Impact: A Method for Evaluating Potential Ecological Impact of Alien Plant Species  

Science.gov (United States)

Alien plant species are stressors to ecosystems and indicators of reduced ecosystem integrity. The magnitude of the stress reflects not only the quantity of aliens present, but also the quality of their interactions with native ecosystems. We develop an Index of Alien Impact ( IAI) to estimate the collective ecological impact of in situ alien species. IAI summarizes the frequency of occurrence and potential ecological impact ( Invasiveness-Impact Score ( I i )) of individual alien species for all aliens present in a particular location or community type. A component metric, I i , is based on ecological species traits (life history, ecological amplitude, and ability to alter ecosystem processes) that reflect mechanisms, which can increase impact to ecosystem structure and function. While I i is less complex than some other multi-metric rankings of alien impact, it compares well to these metrics and to qualitative judgments. IAI can be adapted for different ecological settings by modifying the set of species traits incorporated in I i to reflect properties likely to breach biotic and abiotic barriers or alter ecosystem function in a particular region or community type of interest. To demonstrate our approach, we created versions of IAI and I i , applicable to the diverse streamside vegetation of a river basin (19,631 km2) spanning low-elevation arid to mesic montane habitats in eastern Oregon, USA. In this demonstration effort, we (1) evaluate relationships of IAI to metrics describing invasion level, and (2) illustrate the potential utility of IAI for prioritizing alien species management activities and informing restoration goals.

Magee, Teresa K.; Ringold, Paul L.; Bollman, Michael A.; Ernst, Ted L.

2010-04-01

326

Distinguishing land use types using surface albedo and normalized difference vegetation index derived from the SEBAL model for the Atankwidi and Afram sub-catchments in Ghana  

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Full Text Available Distinguishing land use types is mostly done through field surveys which does not easily capture the spatial changes in the land use/cover types. In this study, the Surface Energy Balance Algorithm for Land (SEBAL model was used to estimate surface albedo and NDVI, for different land use/cover types for two sub-catchments (i.e., Atankwidi and Afram in the Volta Basin of Ghana. The mean coefficient of variation (CV for individual land use/cover types compared to the mean CV for a given site was then used to distinguish among the land use/cover types. It was found that these parameters derived from the SEBAL model can be used to distinguish among different land use/cover types in the two sub-catchments. SEBAL estimates for surface albedo and NDVI across the different land use/cover types varied from 0.05 to 0.22 and -0.41 to 0.38, respectively. The range of CVs for surface albedo and NDVI, were 5-22% and 7-175%, respectively across the different land use/cover types for the two catchments. The results of this study demonstrate that SEBAL’s derived surface albedo and NDVI can be used to distinguish land use/cover types in catchments similar to those of the study areas with few ground measurements.

Tayari Salifu

2012-01-01

327

Forest Fire Ecology.  

Science.gov (United States)

Presents a model that integrates high school science with the needs of the local scientific community. Describes how a high school ecology class conducted scientific research in fire ecology that benefited the students and a state park forest ecologist. (MKR)

Zucca, Carol; And Others

1995-01-01

328

Composição de espécies de Arctiidae (Lepidoptera) no sul do Brasil: relação entre tipos de vegetação e entre a configuração espacial do hábitat / Composition of the Arctiidae species (Lepidoptera) in southern Brazil: relationship among vegetation types and among habitat spatial configuration  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho descreve o padrão de diversidade beta das mariposas Arctiidae no Estado do Rio Grande do Sul (RS) e avalia se esse padrão é relacionado com o tipo de vegetação ou com a distância geográfica entre as áreas. A partir da observação de 9420 espécimes depositados em 13 coleções científicas [...] e de duas listas publicadas na literatura, obteve-se registro de 329 espécies de arctiídeos em 55 localidades do RS. Essa riqueza corresponde a 5,6% da fauna Neotropical e 16,5% da fauna estimada para o Brasil. Cinqüenta e duas espécies (15,8%) foram registradas pela primeira vez no Estado. Não houve relação entre a diversidade beta (distância de Sorensen) e a distância geográfica entre as localidades, sugerindo que a configuração espacial do ambiente não influencia de forma significativa a locomoção das mariposas Arctiidae entre as paisagens. As análises multivariadas indicaram que a fauna de Arctiidae apresenta uma composição diferente em cada tipo de vegetação. A composição da fauna de áreas de Floresta Ombrófila Mista (Mata de Araucária) difere da fauna dos demais tipos de vegetação. Além disso, verificou-se uma maior riqueza de espécies em ambientes florestais do que em campestres. Abstract in english We describe the beta-diversity pattern of the Arctiidae in Rio Grande do Sul State (RS) and assess whether this pattern is related to similarities in vegetation type or geographic distance among areas. We analysed 9420 specimens in 13 scientific collections, as well as two published checklists. Thre [...] e hundred twenty nine arctiid species were recorded for 55 localities. This richness corresponded to 5.6% of the Neotropical fauna, and 16.5% of the estimated Brazilian fauna. Fifty two species (15.8%) were recorded for the first time in the state. There was no relationship between beta-diversity (Sorensen distance) and geographic distance among the localities, suggesting that the spatial configuration of the habitat did not influence significantly the locomotion of the Arctiidae moths among landscapes. The multivariate analysis suggested that the Arctiidae fauna differ among vegetation types. The composition of the fauna at the Floresta Ombrófila Mista (Araucaria forest) is very distinct from other vegetation type faunas. Species richness was higher on forest habitats than in open habitats.

Ferro, Viviane Gianluppi; Teston, José Augusto.

329

Composição de espécies de Arctiidae (Lepidoptera no sul do Brasil: relação entre tipos de vegetação e entre a configuração espacial do hábitat Composition of the Arctiidae species (Lepidoptera in southern Brazil: relationship among vegetation types and among habitat spatial configuration  

Directory of Open Access Journals (Sweden)

Full Text Available Este trabalho descreve o padrão de diversidade beta das mariposas Arctiidae no Estado do Rio Grande do Sul (RS e avalia se esse padrão é relacionado com o tipo de vegetação ou com a distância geográfica entre as áreas. A partir da observação de 9420 espécimes depositados em 13 coleções científicas e de duas listas publicadas na literatura, obteve-se registro de 329 espécies de arctiídeos em 55 localidades do RS. Essa riqueza corresponde a 5,6% da fauna Neotropical e 16,5% da fauna estimada para o Brasil. Cinqüenta e duas espécies (15,8% foram registradas pela primeira vez no Estado. Não houve relação entre a diversidade beta (distância de Sorensen e a distância geográfica entre as localidades, sugerindo que a configuração espacial do ambiente não influencia de forma significativa a locomoção das mariposas Arctiidae entre as paisagens. As análises multivariadas indicaram que a fauna de Arctiidae apresenta uma composição diferente em cada tipo de vegetação. A composição da fauna de áreas de Floresta Ombrófila Mista (Mata de Araucária difere da fauna dos demais tipos de vegetação. Além disso, verificou-se uma maior riqueza de espécies em ambientes florestais do que em campestres.We describe the beta-diversity pattern of the Arctiidae in Rio Grande do Sul State (RS and assess whether this pattern is related to similarities in vegetation type or geographic distance among areas. We analysed 9420 specimens in 13 scientific collections, as well as two published checklists. Three hundred twenty nine arctiid species were recorded for 55 localities. This richness corresponded to 5.6% of the Neotropical fauna, and 16.5% of the estimated Brazilian fauna. Fifty two species (15.8% were recorded for the first time in the state. There was no relationship between beta-diversity (Sorensen distance and geographic distance among the localities, suggesting that the spatial configuration of the habitat did not influence significantly the locomotion of the Arctiidae moths among landscapes. The multivariate analysis suggested that the Arctiidae fauna differ among vegetation types. The composition of the fauna at the Floresta Ombrófila Mista (Araucaria forest is very distinct from other vegetation type faunas. Species richness was higher on forest habitats than in open habitats.

Viviane Gianluppi Ferro

2009-06-01

330

Variabilidade morfológica foliar de Miconia sellowiana (DC. Naudin (Melastomataceae em diferentes fitofisionomias no Estado do Paraná Leaf morphology variation of Miconia sellowiana (DC. Naudin (Melastomataceae in distinct vegetation types at the state of Paraná  

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Full Text Available Este estudo investigou a morfologia foliar de Miconia sellowiana, ocorrente em quatro diferentes fitofisionomias: Estepe Gramíneo-Lenhosa (EGL, Floresta Ombrófila Densa Montana (FODM, Floresta Ombrófia Mista (FOM e Floresta Ombrófila Densa Alto-Montana (FODAM, no Estado do Paraná, Brasil. Ramos de seis indivíduos de cada fitofisionomia foram coletados, sendo selecionadas 20 folhas por indivíduo. A área foliar, massa seca foliar, área foliar específica, densidades de tricomas e de estômatos, espessura da cutícula, espessura total e dos tecidos da lâmina foliar foram analisados. As características morfológicas foliares variaram significativamente para os parâmetros analisados. As folhas de M. sellowiana da EGL e FODAM apresentaram características mais xeromórficas, com os maiores valores médios para densidade estomática e de tricomas, maiores espessuras da cutícula da face adaxial, do parênquima esponjoso e espessura total da lâmina e os menores valores médios para a área e massa seca foliar e área foliar específica. A análise de variância e a análise dos componentes principais detectaram um gradiente de mesofilia/xeromorfia entre as quatro fitofisionomias: FOM>FODM>EGL>FODAM. Aparentemente, as diferenças encontradas estão associadas com vários fatores ambientais, principalmente com as características do solo e a intensidade luminosa.This study investigated the leaf morphology of Miconia sellowiana, in four different vegetation types: Grassland (EGL, Montane Atlantic Forest (FODM, Upper Montane Atlantic Forest (FODAM, and Araucaria Forest (FOM, at the state of Paraná, Brazil. Twenty leaves were selected from six individuals from each vegetation type. Several leaf parameters were analyzed including leaf area, leaf dry mass, specific leaf area (SLA, trichomes and stomata densities, and anatomical measurements. The leaves of M. sellowiana from EGL and FODAM presented pronounced xeric characteristics, with higher mean values for stomata density, trichome density on the adaxial surface, thickness of the cuticle of adaxial epidermis, spongy parenchyma, and total lamina thickness; and lower mean values for leaf area, dry leaf mass, and specific leaf area. The use of ANOVA and PCA detected a mesophylly-to-xeromorphy gradient among the four vegetation types: FOM>FODM>EGL>FODAM. The differences are apparently associated to several environmental conditions, mainly soil characteristics and light intensity.

Maria Regina Torres Boeger

2008-09-01

331

The use of vegetation structure measures to improve habitat classification  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The methods used to determine habitat classifications are important to planning and management. Therefore, the use of wildlife communities to improve habitat classification is crucial in Landscape Ecology. The importance of vegetation in the habitat use characteristics of breeding bird communities occurring in Évora (Portugal) was studied.

Quinta-nova, L. C.

1999-01-01

332

The study on remote sensing inversion of ecological environmental indices and their dynamic analysis in the six karst peak cluster areas, Guangxi  

Science.gov (United States)

Karst Peak Cluster areas are main type of karst landform in Guangxi, which are as controllers of ecological environment to plays a important role in Guangxi. It has important practical significance to dynamic monitor and appraisal Guangxi's ecological environment. Paper choose EOS/MODIS remote sensing data for five period. Based on the necessity argument for giving domain and quantitative remote sensing, Doing a inversion to the Normalized Difference Vegetation Index NDVI and Vegetation coverage FC remote-sensing of Du'an, Debao, Liujiang, Nandan, Jingxi and Fengshan, where the six main Karst Peak-Cluster giving domain areas of Guangxi, And paper studied the longitudinal variance analysis and the horizontal inversion variance analysis for the inversion result .it shows that, any calculations which involves applying statistical characteristics -- the average value-variance-covariance and maximum / minimum value of image processing algorithm, should adopt the giving domain image processing algorithm model. Analysis of six karst peak cluster area FC longitudinal changes ,we find that The tendency of vegetation coverage of Six major karst peak cluster is" down then up", but in general they were rising,; analysis of horizontal changes in Guangxi six major karst peak cluster vegetation coverage, Find that before 2008,the karst Peak-Cluster areas of Guangxi FC had West high and East low" spatial variation. after 2008, it had" North high South low" spatial variation.

Jia, Zhiqiang; Wu, Hong; Hao, Min; Xing, Lixin

2014-05-01

333

Wildfire History and Ecology  

Science.gov (United States)

Part of a great site on the land use history of the Colorado Plateau from Northern Arizona University, this site 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.

2008-09-17

334

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  

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Full Text Available 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 fanerógamas 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.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 phanerophytes. 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

2003-06-01

335

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.

336

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

337

Ecology of mosquitoes of Midwestern Nigeria  

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Full Text Available Background & objectives: The ecology and distribution of various mosquito species is important inthe determination of mosquito vector abundance and associated diseases prevalence. The distributionof various mosquito genera in natural and artificial habitats and their relative species abundancewas studied between August 2002 and July 2003 in three foci (Uromi, Ekpoma and Auchi comprisingthe Esan and Etsako regions of Midwestern Nigeria.Methods: Sampling was carried out by the method of Hopkins (1952 by dipping using a pipette orladle depending on container types. Pooled contents of smaller containers were sampled with a pondnet. All breeding sources of mosquito larvae were grouped into five (5 depending on their nature,constitution and the physiochemical properties. Artificial mosquito cultures were also carried out infour different container types; plastics, metal cans, earthenware pots and bamboo strips, in parts oftwo different macro habitats subdivided into area of high human activities (AHHA and areas ofderived/secondary vegetation (ADSV. Environmental temperatures, rainfall and relative humiditywere monitored during the study.Results: The present study revealed 17 mosquito species belonging to three genera (Anopheles,Culex and Aedes which are potential vectors of four human diseases in the areas surveyed. A total of736 mosquito larvae were encountered in artificial sources and 568 larvae were harvested from naturalsources. Pools, plastics and metal cans were the predominant artificial sources of mosquito larvae.Conclusion: The contribution of human activities and increasing environmental modification to thebreeding of human disease vector mosquitoes is of importance and selective vector control measuresincluding larviciding are recommended particularly before onset of rainy season

Godwin R.A. Okogun, Jude C. Anosike, Anthony N. Okere & Bethran E.B. Nwoke

2005-03-01

338

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

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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

339

Research on Chengdu Vegetables Marketing Based on STP Model  

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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 ...

Qiang Liu; Xiumin Wu

2013-01-01

340

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

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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...

2013-01-01

 
 
 
 
341

SYSTEMATICS AND ECOLOGY OF DANISH SALT MARSH COMMUNITIES  

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A review of salt marsh communities and submerged saline communities in Denmark is presented. A total of 24 communities has been recognised from published accounts of Danish salt marsh vegetation along with own investigations. A floristical classification based on TWINSPAN analysis of 696 relevées has been performed. For each community the existing knowledge on ecology, succession and impacts of management are summarized.

Nygaard, B.; Lawesson, J. E.

1998-01-01

342

ECOLOGICAL IMPACT OF INTEGRATED CHEMICAL AND BIOLOGICAL AQUATIC WEED CONTROL  

Science.gov (United States)

This final report presents results of a four-year study of the ecological impacts of chemical, biological, and integrated methods of aquatic weed control. Biological and water quality changes occurred as abundance of macrophytic vegetation was altered by natural factors or manage...

343

Coastal Sand Dune Plant Ecology: Field Phenomena and Interpretation  

Science.gov (United States)

Discusses the advantages and disadvantages of selecting coastal sand dunes as the location for field ecology studies. Presents a descriptive zonal model for seaboard sand dune plant communities, suggestions concerning possible observations and activities relevant to interpreting phenomena associated with th