The influence of some ecological factors to aquatic and marsh vegetation was studied during 1998-2000. Three basic vegetation units (Caricetum buekii, Typhetum latifoliae and Ceratophylletum submersi) and three transitional communities were defined in the belt transect, which was established along the moisture gradient. The content of available soil nutrients in individual vegetation types differed only in case of the Ceratophyllum submersum community, where a higher magnesium and nitrogen co...
Dynamic global vegetation models are a powerful tool to project the past, current and future distribution of vegetation and associated water and carbon fluxes. However, most models are limited by how they define vegetation and by their simplistic representation of competition. We discuss how concepts from community assembly theory and coexistence theory can help to improve vegetation models. We further present a new trait- and individual-based dynamic vegetation model (the aDGVM2) that allows each individual plant to adopt a unique combination of trait values. These traits define how each individual plant grows and competes with other plants under given environmental conditions. The performance of individual plants in turn drives the assembly of a plant community. A genetic optimisation algorithm is used to simulate the inheritance of traits and different levels of reproductive isolation between individuals. Together these model properties allow the assembly of plant communities that are well adapted to a site's biotic and abiotic conditions. Simulated communities can be classified into different plant functional types or biome types by using trait data bases. We illustrate that the aDGVM2 can simulate (1) how environmental conditions and changes in these conditions influence the trait spectra of assembled plant communities, (2) that fire selects for traits that enhance fire protection and reduces trait diversity, and (3) the emergence of communities dominated by life history strategies that are suggestive of colonisation-competition trade-offs. The aDGVM2 deals with functional diversity and competition fundamentally differently from current dynamic vegetation models. We argue that this approach will yield novel insights as to how vegetation may respond to climate change and we believe that it could foster fruitful collaborations between research communities that focus on plant functional traits, plant competition, plant physiology, systems ecology and earth system science.
Scheiter, Simon; Higgins, Steven; Langan, Liam
Full Text Available The influence of some ecological factors to aquatic and marsh vegetation was studied during 1998-2000. Three basic vegetation units (Caricetum buekii, Typhetum latifoliae and Ceratophylletum submersi and three transitional communities were defined in the belt transect, which was established along the moisture gradient. The content of available soil nutrients in individual vegetation types differed only in case of the Ceratophyllum submersum community, where a higher magnesium and nitrogen content accumulated due to specific environmental conditions. Water and marsh vegetation is usually characterised by a pronounced spatial and temporal dynamics. In the studied area, its zonation was dependent from the terrain morphology, and both depth and duration of floods. The fluctuation of ground and surface water table during a three-year period caused changes in the occurrence and cover of several species (e.g. Carex buekii, Typha latifolia, aquatic macrophytes. Pronounced changes in the cover of some species occurred even within a single vegetation season due to the long-term sink of water table below the ground surface.
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.
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
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.
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.
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.
Species turnover across elevational gradients has matured into an important paradigm of community ecology. Here, we tested whether ecological and phylogenetic structure of skipper butterfly assemblages is more strongly structured according to altitude or vegetation type along three elevation gradients of moderate extent in Serra do Mar, Southern Brazil. Skippers were surveyed along three different mountain transects, and data on altitude and vegetation type of every collection site were recor...
Carneiro, Eduardo; Mielke, Olaf Hermann Hendrik; Casagrande, Mirna Martins; Fiedler, Konrad
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
By the methods of TWINSPAN, DCA and DCCA, and from the aspects of the relations between plant species, communities and environmental factors, this paper studied the ecological relationships among artificial vegetations during their restoration in Antaibao mining area. 63 collected quadrates were classified into 12 community types by TWINSPAN, and the distribution of the communities could comprehensively reflect the influence of environmental factors. DCA ordination indicated that soil water content, which was increased with restoration time, was the main factor restricting the distribution of the communities. DCCA ordination showed that soil organic matter content was the decisive factor to the development of communities. PMID:15852977
Zhang, Guilian; Zhang, Jintun; Guo, Xiaoyu
We are attempting to set up a new protocol for palaeoecological reconstruction in relation to the fossil hominin site Laetoli, Tanzania. This is based on the premise that habitat variability in the past was at least as great as at present; that this variability at the landscape level is a function of variations in geology, soils, and topography rather than climate; and that vegetation type at the landscape level can be reconstructed from these environmental variables. Measurable variation in climate in tropical Africa today occurs over distances of at least 100 km, so that ranges of habitat variation within the limited area of Laetoli today can be reconstructed in relation to soils and topography, and the effects of climate changes are then estimated in relation to these other factors. In order to document the modern vegetation, we have made voucher collections of plants in the Laetoli region, recorded distributions of plants by habitat, climate, soil, and topography, and mapped the vegetation distributions. Results show that areas of low relief have soils with impeded drainage and dense Acacia drepanolobium woodland, having low canopies when disturbed by human action, higher when not; shallow brown soils on volcanic lavas have four woodland associations, two dominated by Acacia species, two by Combretum-Albizia species; shallow volcanic soils to the east have a woodland association with Croton-Dombeya-Albizia species; elevated land to the east on volcanic soils has two associations of montane-edge species, one with Croton-Celtis-Lepidotrichilia, and the other with Acacia lahai; the eastern highlands above 2,750 m have montane forest; seasonal water channels flowing from east to west have three Acacia riverine woodland associations; three deep valleys to the north of the area have dense riverine woodland with Celtis, Albizia, Euclea, Combretum, Acacia spp.; emergence of springs at Endulen feed a perennial stream with closed gallery forest with Ficus-Croton-Lepidotrichilia; and, finally, recent ash falls have produced immature alkaline soils with calcrete formation and short grass vegetation. All of these vegetation associations have been modified by human disturbance to greater or lesser degrees, and we have attempted to allow for this both by basing the associations on the least modified areas and by predicting how the associations, or parts of associations, have been altered by human action. Past land forms at Laetoli have been based on the geology and geomorphology of the area. Past vegetation patterns were estimated by superimposing present distributions of plant associations on equivalent landforms in the past, assuming similar climate to the present. This indicates the overall pattern of vegetation at Laetoli to have been a mosaic of low and tall deciduous woodlands and with riverine woodland and forest associations along water courses. Low woodlands would have been dominated by Acacia species, and tall woodlands by Combretum-Albizia species, with increasing increments of montane species, such as Croton species, to the east of the area. Riverine woodlands would have been dominated by Acacia-Euclea species, with wetter associations (downriver or linked with spring activity) supporting gallery forest with Ficus, Celtis, and Croton species. These are all species associations common in the area today, and with landforms little changed in the past, and assuming similar climate, there is every reason to predict that they would have been present in the past. Moreover, Pliocene environments lack the human disturbance that has destroyed much of the present day vegetation. Presence of woodlands is supported by fossil wood attributed to several of the tree species present in the area today and by similarities in the mammalian community structure between past and present. Having established the pattern for Pliocene vegetation based on climatic variables existing today, we then predict the effects of past variations in climate. PMID:17765945
Andrews, Peter; Bamford, Marion
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.
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
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 mov [...] ement 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.
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 H 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
Based on the data obtained from 72 plant community plots and 276 plant species in Hulunbeier Sandy Land and Kerqin Sandy Land in the northeast desertification region of China, TWINSPAN analysis was carried out. Meanwhile the practical classification result was obtained by Detrended correspondence Analysis (DCA). Under the vegetation classification principles of China, the vegetation classification system of the desertification regions in northeast China was preliminarily established, which includes 6 vegetation types, 11 subtypes, 40 formations, and 55 associations. PMID:11767570
Guan, W; Zeng, D; Jiang, F
Terrestrial vegetation is an interactive component of the climate system. Dynamic Global Vegetation Models (DGVMs) simulate vegetation dynamics at the global scale and include it into Earth System Models. DGVMs are mostly based on the carbon balance of above- and below-ground biomass, and vegetation dynamics are influenced by climatic conditions and a variety of disturbances. They include a limited number of mechanisms to represent different types of vegetation and disturbances. T...
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.)
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
Watermelon, tomato and other vegetable crops are infected by a wide variety of viral pathogens, many of which are transmitted by whiteflies. The inter-related ecology and management of four such viruses currently present in Florida, Squash vein yellowing virus, Cucurbit leaf crumple virus, Tomato y...
Outbreaks of illness due to human enteric pathogenic bacteria via fresh vegetables warrant intensive research on changing strategies of these bacteria in alterning their hosts for survival. The systemic infection of human pathogenic bacteria in plants and the plant growth stage at which they establish endophytic relationship is poorly understood. The issue is magnified in countries like India where the dietary habits are changing and consumption of fresh fruits ...
Nithya, A.; Gothandam, K. M.; Babu, S.
Full Text Available 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.
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.
Wetlands constitute very important ecological areas. The aim of this study was to quantify the soil losses due to fluvial erosion from 2006 to 2008 in two riverbanks under three types of vegetal coverage dominated by Haematoxylum campechianum, Dalbergia brownei and Brachiaria mutica, in the Pantanos de Centla Biosphere Reserve, SE Mexico. The relationship between the texture, organic matter and pH of soils and soil losses was evaluated. We used erosion sticks to estimate soil losses in 18 plots (three plots per type, three vegetation types, two riverbanks). Soil loss decreased in this order: H. campechianum>B. mutica>D. brownei indicating that D. brownei scrubland has the most potential to retain soil. The higher erosive impact within H. campechianum sites can be related with the low density of these trees in the study areas, as well as the lack of association with other types of vegetation that could reinforce the rooting of the soil profile. Furthermore, soil losses in H. campechianum sites were dependent on soil texture. The soils under this type of vegetal coverage were mainly sandy, which are more vulnerable to the erosive action in comparison with fine textured soils or soils with higher clay content, like the ones found in D. brownei and B. mutica sites. Soil losses of 100 % in the second year (B. mutica plots) can be attributed to the distribution of roots in the upper soil layer and also to livestock management along riverbanks. This study recognizes the importance of D. brownei scrublands in riverbank soil retention. Nevertheless it is necessary to consider the role of an entire vegetal community in future research. PMID:20073341
Sepúlveda-Lozada, Alejandra; Geissen, Violette; Ochoa-Gaona, Susana; Jarquín-Sánchez, Aarón; de la Cruz, Simón Hernández; Capetillo, Edward; Zamora-Cornelio, Luis Felipe
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
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
Ro?. 42, - (2007), s. 199-208. ISSN 1211-9520 R&D Projects: GA AV ?R IAA6163303; GA ?R(CZ) GA206/05/0020 Grant ostatní: GA AV ?R(CZ) KJB601630504 Institutional research plan: CEZ:AV0Z60050516 Keywords : Ecological methodology * Large-scale vegetation patterns * Macroecology Subject RIV: EF - Botanics Impact factor: 1.133, year: 2007
Role?ek, J.; Chytrý, M.; Hájek, Michal; Lvon?ík, S.; Tichý, L.
In this study, we compared ecological characteristics of wetland vegetation in a series of restoration projects that were carried out in the wetlands of Yellow River Delta. The investigated characteristics include plant composition structure, species diversity and community similarity in three kinds of Phragmites australis wetlands, i.e. restored P. australis wetlands (R1, R2, R3 and R4: restored in 2002, 2005, 2007 and 2009, respectively), natural P. australis wetland (N) and degraded P. aus...
Wang, Xuehong; Yu, Junbao; Zhou, Di; Dong, Hongfang; Li, Yunzhao; Lin, Qianxin; Guan, Bo; Wang, Yongli
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.
This paper applies multivariate statistical methods to a data set of weed relevés from arable fields in two different habitat types of coastal and mountainous escarpments in Southern Oman. The objectives were to test the effect of environmental gradients, crop plants and time on weed species composition, to rank the importance of these particular factors, and to describe the patterns of species composition and diversity associated with these factors. Through the application of TWINSPAN, DCA and CCA programs on data relating to 102 species recorded in 28 plots and farms distributed in the study area, six plant communities were identified: I- Dichanthium micranthum, II- Cynodon dactylon-D. micranthum, III- Convolvulus arvensis, IV- C. dactylon-Sonchus oleraceus, V- Amaranthus viridis and VI- Suaeda aegyptiaca-Achyranthes aspera. The ordination process (CCA) provided a sequence of plant communities and species diversity that correlated with some anthropogenic factors, physiographic variables and crop types. Therefore, length of time since farm construction, disturbance levels and altitude are the most important factors related to the occurrence of the species. The perennial species correlated with the more degraded mountain areas of new farm stands, whereas most of the annuals correlated with old lowland and less disturbed farms. PMID:23961246
El-Sheikh, Mohamed A
Vegetation survey is an important research agenda in vegetation science. It defines vegetation types and helps understand differences among them, which is essential for both basic ecological research and applications in biodiversity conservation and environmental monitoring. In this editorial, we reflect on the historical development and current state of vegetation survey worldwide and introduce the Special Feature ‘Vegetation Survey’, as well as the new section of the same name in Applie...
Chytry, M.; Schaminee, J. H. J.; Schwabe, A.
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 for understanding vegetation dynamics under the present climate, and for predicting 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 modeling. The outcomes of the models, which include different mechanisms, are compared to observed tree cover along a mean annual precipitation gradient in Africa. 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 improved representation in the examined 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 presence 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 forest trees, and fire-resistant and shade-intolerant savanna 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.
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.
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
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
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.
This research describes modern phytolith records and distributions from subalpine surface soils in the Dalaoling Forest Reserve, and reveals its implications for local climate conditions with respect to the altitude gradient. Well-preserved phytolith morpho-types, assemblages, and climatic indices were used to study the relationship between local vegetation and climate conditions. The phytolith classification system is mainly based on the characteristics of detailed morpho-types described for anatomical terms, which are divided into seven groups: long cells, short cells, bulliform cells, hair cells, pteridophyte type, broad-leaved type, and gymnosperm type. Phytoliths originating from the Poaceae are composed of Pooideae (rondel and trapeziform), Panicoideae (bilobate, cross, and polylobate), Chloridoideae (short/square saddle), and Bambusoideae (oblong concave saddle). Based on the altitudinal distribution of the phytolith assemblages and the indices of aridity (Iph), climate (Ic), and tree cover density (D/P), five phytolith assemblage zones have revealed the five types of climatic conditions ranging from 1,169 m to 2,005 m in turn: warm-wet, warm-xeric to warm-mesic, warm-xeric to cool-mesic, cool-xeric, and cool-mesic to cool-xeric. The Bambusoideae, Panicoideae, and Chloridoideae are the dominant vegetation at the lower-middle of the mountains, while Pooideae is mainly distributed in the higher mountains. The close relationship between phytolith assembleages and changes of altitude gradient suggest that vegetation distribution patterns and plant ecology in the Dalaoling mountains are controlled by temperature and humidity conditions. Our results highlight the importance of phytolith records as reliable ecoclimatic indicators for vegetation ecology in subtropical regions.
Traoré, Djakanibé Désiré; Gu, Yansheng; Liu, Humei; Shemsanga, Ceven; Ge, Jiwen
Full Text Available Ecosystem entropy production is predicted to increase along ecological succession and approach a state of maximum entropy production, but few studies have bridged the gap between theory and data. Here, we explore radiative entropy production in terrestrial ecosystems using measurements from 64 Free/Fair-Use sites in the FLUXNET database, including a successional chronosequence in the Duke Forest in the southeastern United States. Ecosystem radiative entropy production increased then decreased as succession progressed in the Duke Forest ecosystems, and did not exceed 95% of the calculated empirical maximum entropy production in the FLUXNET study sites. Forest vegetation, especially evergreen needleleaf forests characterized by low shortwave albedo and close coupling to the atmosphere, had a significantly higher ratio of radiative entropy production to the empirical maximum entropy production than did croplands and grasslands. Our results demonstrate that ecosystems approach, but do not reach, maximum entropy production and that the relationship between succession and entropy production depends on vegetation characteristics. Future studies should investigate how natural disturbances and anthropogenic management—especially the tendency to shift vegetation to an earlier successional state—alter energy flux and entropy production at the surface-atmosphere interface.
Paul C. Stoy
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
Full Text Available SciELO Brazil | Language: English Abstract in portuguese As mudanças globais englobam importantes alterações nos padrões normais de processos bioquímicos e biofísicos da Terra. Os reais efeitos e retroalimentações das mudanças globais sobre a vegetação ainda são incertos. Parte das incertezas pode ser atribuída à falta de atenção de cientistas e políticos [...] para a vegetação, enquanto componente do sistema terrestre. Entretanto, algumas questões sobre as mudanças globais poderiam ser mais bem esclarecidas por abordagens mais voltadas à ecofisiologia vegetal. Nesse artigo, alguns pontos relacionados e esses problemas, como as limitações em se abordar a vegetação como um componente estático da atmosfera enquanto outros subsistemas do sistema terrestre são dinâmicos, são discutidos. Dentro dessa perspectiva, essa revisão traz uma reflexão inicial do papel da vegetação, em termos de estrutura e funcionamento, no contexto das mudanças globais. Para isso, foi feita uma revisão das terminologias relacionadas às mudanças globais e ao sistema terrestre, buscou-se ilustrar alguns dos principais temas de pesquisa da ecofisiologia vegetal no contexto das mudanças globais. Foram feitas considerações em relação ao tratamento de plantas como sistemas complexos, o que é importante para o estudo de aspectos relacionados à sensibilidade, estabilidade e vulnerabilidade a variações ambientais. Finalmente, são discutidas alternativas que podem ser utilizadas para incorporar aspectos do funcionamento da vegetação, de forma dinâmica, em estudos de mudanças globais, considerando o desafio de mudança de escalas. Espera-se que essa revisão possa auxiliar pesquisadores subsidiando suas estratégias de identificação e compreensão dos efeitos potenciais das mudanças globais sobre os processos mais vulneráveis da vegetação, da folha ao globo. Abstract in english The global changes are marked by alteration on the normal patterns of important biochemical and biophysical processes of the Earth. However, the real effects as well as the feedbacks of the global changes over vegetation are still unclear. Part of this uncertainty can be attributed to the inattentio [...] n of stakeholders and scientists towards vegetation and its complex interrelations with the environment, which drive plant physiological processes in different space-time scales. Notwithstanding, some key subjects of the global changes could be better elucidated with a more plant physiological ecology approach. We discuss some issues related to this topic, going through some limitations of approaching vegetation as a static component of the biosphere as the other sub-systems of the Earth-system change. With this perspective, this review is an initial reflection towards the assessment of the role and place of vegetation structure and function in the global changes context. We reviewed the Earth-system and global changes terminology; attempted to illustrate key plant physiological ecology researches themes in the global changes context; consider approaching plants as complex systems in order to adequately quantify systems characteristics as sensibility, homeostasis, and vulnerability. Moreover, we propose insights that would allow vegetation studies and scaling procedures in the context of the Earth-system. We hope this review will assist researchers on their strategy to identify, understand and anticipate the potential effects of global changes over the most vulnerable vegetation processes from the leaf to the global levels.
João Paulo Rodrigues Alves Delfino, Barbosa; Serge, Rambal; Angela Maria, Soares; Florent, Mouillot; Joana Messias Pereira, Nogueira; Giordane Augusto, Martins.
Species turnover across elevational gradients has matured into an important paradigm of community ecology. Here, we tested whether ecological and phylogenetic structure of skipper butterfly assemblages is more strongly structured according to altitude or vegetation type along three elevation gradients of moderate extent in Serra do Mar, Southern Brazil. Skippers were surveyed along three different mountain transects, and data on altitude and vegetation type of every collection site were recorded. NMDS ordination plots were used to assess community turnover and the influence of phylogenetic distance between species on apparent community patterns. Ordinations based on ecological similarity (Bray-Curtis index) were compared to those based on phylogenetic distance measures (MPD and MNTD) derived from a supertree. In the absence of a well-resolved phylogeny, various branch length transformation methods were applied together with four different null models, aiming to assess if results were confounded by low-resolution trees. Species composition as well as phylogenetic community structure of skipper butterflies were more prominently related to vegetation type instead of altitude per se. Phylogenetic distances reflected spatial community patterns less clearly than species composition, but revealed a more distinct fauna of monocot feeders associated with grassland habitats, implying that historical factors have played a fundamental role in shaping species composition across elevation gradients. Phylogenetic structure of community turned out to be a relevant additional tool which was even superior to identify faunal contrasts between forest and grassland habitats related to deep evolutionary splits. Since endemic skippers tend to occur in grassland habitats in the Serra do Mar, inclusion of phylogenetic diversity may also be important for conservation decisions. PMID:25272004
Carneiro, Eduardo; Mielke, Olaf Hermann Hendrik; Casagrande, Mirna Martins; Fiedler, Konrad
Full Text Available There is increasing demand for reliable, high-resolution vegetation maps covering large areas. Airborne laser scanning data is available for large areas with high resolution and supports automatic processing, therefore, it is well suited for habitat mapping. Lowland hay meadows are widespread habitat types in European grasslands, and also have one of the highest species richness. The objective of this study was to test the applicability of airborne laser scanning for vegetation mapping of different grasslands, including the Natura 2000 habitat type lowland hay meadows. Full waveform leaf-on and leaf-off point clouds were collected from a Natura 2000 site in Sopron, Hungary, covering several grasslands. The LIDAR data were processed to a set of rasters representing point attributes including reflectance, echo width, vegetation height, canopy openness, and surface roughness measures, and these were fused to a multi-band pseudo-image. Random forest machine learning was used for classifying this dataset. Habitat type, dominant plant species and other features of interest were noted in a set of 140 field plots. Two sets of categories were used: five classes focusing on meadow identification and the location of lowland hay meadows, and 10 classes, including eight different grassland vegetation categories. For five classes, an overall accuracy of 75% was reached, for 10 classes, this was 68%. The method delivers unprecedented fine resolution vegetation maps for management and ecological research. We conclude that high-resolution full-waveform LIDAR data can be used to detect grassland vegetation classes relevant for Natura 2000.
Consumption of dark green vegetables falls short of recommendations, in part, because of unpleasant bitterness. A laboratory-based study of 37 adults was used to determine bitter and hedonic responses to vegetables (asparagus, Brussels sprouts, kale) with bitter masking agents (1.33 M sodium acetate, 10 and 32 mM sodium chloride, and 3.2 mM aspartame) and then characterized by taste phenotype and vegetable liking. In repeated-measures ANOVA, aspartame was most effective at suppressing bittern...
Sharafi, Mastaneh; Hayes, John E.; Duffy, Valerie B.
In ecological systems of vegetable cultivation (hortic antrosols; soils from greenhouses), exists an ensemble of equilibriums between organic-mineral combinations, very sensitive even to relatively small variations of physical-chemical conditions in soils. As such, these can manifest a strong influence on organic matter, clay minerals and microelements from soil, which in turn impacts on the productivity of these soils and the quality of obtained products (vegetables, fruit). Although many studies consider these organic-mineral combinations are meta-stable combinations, our work has shown that the stability of organic-mineral combinations in hortic antrosols (especially for clay-humic, clay-ironhumic combinations and chelates) is higher. We believe that this is due to the higher flexibility of these combinations' structures with the variation of chemical-mineralogical composition and physical-chemical conditions in soil. This paper highlights the results of our research on the differentiation possibility of organic-mineral complexes, depending on their structure and composition (using Raman and FT-IR spectrometry) and the influences manifested by the organic-mineral complexes on the micro-elements dynamic from ecological systems of fresh vegetable cultivation. The non-destructive separation of organic-mineral compounds from soil samples was carried out through iso-dynamic magnetic separation and extraction in aqueous two-phase systems (PEG-based). The Raman and FT-IR spectrometry analyses on raw soil samples, extracts obtained from soil samples and separated mineral fractions have been supplemented by the results obtained through chemical, microscopic and thermal analyses and by UV-VIS absorption spectrometry. Ours experimental studies have been done on representative samples of hortic antrosol from Copou glasshouse (Iasi, Romania), and was studied five micro-elements: Zn, Ni, Cu, Mn, Cr and P. The total contents of the five microelements and their fractions differential bonded on mineral and organic components of hortic antrosols, have been determined by atomic absorption spectrometry after combined sequential extraction in solid phase extraction - aqueous biphasic (PEG based) systems. The specific mechanisms of the microelements interaction with organic components have been estimated on the basis of studies realized on fractions obtained after each extraction step by Raman and FTIR spectrometry. These data have been correlated with those obtained by chemical analysis and UV-VIS spectrometry. In conditions of hortic antrosol, from total contents of Zn, Ni, Cu, Mn and Cr, more than 65 % are binding on organic components. A specific phenomenon of hortic antrosols is the microelements complexation exclusively with the functional groups of organic macromolecules. This phenomenon has two important consequences: (i) the strong fixation of microelements (these can be extracted only in very extremely conditions, which implied the organic part destroying) and (ii) their presence determined major modifications in the structure, conformation and stability of organic macromolecules. Under these conditions, the type and structure of organic-mineral compounds represent determinant factors for the dynamic of micro-elements and organic compounds in ecological systems of vegetables cultivation. Acknowledgments The authors would like to acknowledge the financial support from Romanian Ministry of Education and Research (Project PNCDI 2-D5 no. 51045/07 an Project PNCDI 2-D5 no. 52141 / 08).
Bulgariu, D.; Buzgar, N.; Bulgariu, L.; Rusu, C.; Munteanu, N.
We tested if rooting mass and root nutrient uptake of cheatgrass (Bromus tectorum) or creeping wildrye (Leymus triticoides) were influenced by vegetation soil type. Three soil types (A horizons), similar in gross physical and chemical properties, were freshly-collected. The soils varied in the veget...
We examined sexual differences in patterns of vegetation structure selection in the sexually dimorphic little bustard. Differences in vegetation structure between male, female and non-used locations during reproduction were examined and used to build a presence/absence model for each sex. Ten variables were measured in each location, extracting two PCA factors (PC1: a visibility-shelter gradient; PC2: a gradient in food availability) used as response variables in GLM explanatory models. Both factors significantly differed between female, male and control locations. Neither study site nor phenology was significant. Logistic regression was used to model male and female presence/absence. Female presence was positively associated to cover of ground by vegetation litter, as well as overall vegetation cover, and negatively to vegetation density over 30 cm above ground. Male presence was positively related to litter cover and short vegetation and negatively to vegetation density over 30 cm above ground. Models showed good global performance and robustness. Female microhabitat selection and distribution seems to be related to the balance between shelter and visibility for surveillance. Male microhabitat selection would be related mainly to the need of conspicuousness for courtship. Accessibility to food resources seems to be equally important for both sexes. Differences suggest ecological sexual segregation resulting from different ecological constraints. These are the first detailed results on vegetation structure selection in both male and female little bustards, and are useful in designing management measures addressing vegetation structure irrespective of landscape composition. Similar microhabitat approaches can be applied to manage the habitat of many declining farmland birds.
Morales, M. B.; Traba, J.; Carriles, E.; Delgado, M. P.; de la Morena, E. L. García
Full Text Available Many studies have investigated the water relations of indigenous plants in the fynbos shrublands of the Cape, South Africa. These have mainly focused on understanding the mechanisms by which individual plant species respond to droughts, the frequency and severity of which is expected to increase due [...] to climate change. However, comparatively little information exists on the dynamics of water use by indigenous plants in the region, and, in particular, how water use varies seasonally and between sites. In this study we determined water use by 3 fynbos vegetation types growing at 4 different sites, namely: (i) lowland Atlantis Sand Plain fynbos growing on deep sandy soils, (ii) Kogelberg Sandstone fynbos growing in a riparian zone on deep alluvial soils, (iii) dryland Kogelberg Sandstone fynbos growing on shallow sandy soils at a montane site, and (iv) alluvial Swartland fynbos growing in clayey soils. Evapotranspiration (ET) was quantified at each site during specific periods using a boundary layer scintillometer and energy balance system. A simple dual source model in which the stand ET was calculated as the algebraic sum of outputs from soil evaporation and transpiration sub-models was used to scale up the ET measurements to annual values. The data showed large differences in ET depending on site characteristics and on plant attributes. Dense stands of riparian Sandstone Fynbos had an annual ET of 1 460 mm which exceeded the reference ET of 1 346 mm. Dryland Sandstone Fynbos used only 551 mm of water per year while the Sand Plain Fynbos' annual ET was 1 031 mm, which was similar to the reference ET of 1 059 mm. We conclude that some indigenous plant species use large volumes of water which should be accounted for in, e.g., groundwater recharge estimates, and calculations of incremental water gains after clearing alien invasive plants, among other applications
S, Dzikiti; NZ, Jovanovic; R, Bugan; S, Israel; DC, Le Maitre.
This review synthesizes the state of knowledge on fire effects on vegetation and soils in semi-arid ecosystems in the Great Basin Region, including the central and northern Great Basin and Range, Columbia River Basin, and the Snake River Plain. We summarize available literature related to: (1) the effects of environmental gradients, ecological site, and vegetation characteristics on resilience to disturbance and resistance to invasive species; (2) the effects of fire on individual plant species and communities, biological soil crusts, seed banks, soil nutrients, and hydrology; and (3) the role of fire severity, fire versus fire surrogate treatments, and post-fire grazing in determining ecosystem response. From this, we identify knowledge gaps and present a framework for predicting plant successional trajectories following wild and prescribed fires and fire surrogate treatments. Possibly the three most important ecological site characteristics that influence a site’s resilience (ability of the ecological site to recover from disturbance) and resistance to invasive species are soil temperature/moisture regimes and the composition and structure of vegetation on the ecological site just prior to the disturbance event.
Miller, Richard F.; Chambers, Jeanne C.; Pyke, David A.; Pierson, Fred B.; Williams, C. Jason
In this study, we compared ecological characteristics of wetland vegetation in a series of restoration projects that were carried out in the wetlands of Yellow River Delta. The investigated characteristics include plant composition structure, species diversity and community similarity in three kinds of Phragmites australis wetlands, i.e. restored P. australis wetlands (R1, R2, R3 and R4: restored in 2002, 2005, 2007 and 2009, respectively), natural P. australis wetland (N) and degraded P. australis wetland (D) to assess the process of wetlands restoration. The coverage of the R1 was 99%, which was similar to natural wetland. Among all studied wetlands, the highest and lowest stem density was observed in R1 and R2, respectively, Plant height and stem diameter show the same trend as N > R2 > R1 > R3 > D > R4. Species diversity of restored P. australis wetlands became closed to natural wetland. Both species richness and Shannon-Wiener index had similar tendency: increased first and then decreased with restored time. The highest species richness and species diversity were observed in R2, while the lowest values of those parameters were found in natural P. australis wetland. Similarity indexes between restored wetlands and natural wetland increased with the restoration time, but they were still less than 50%. The results indicate that the vegetation of P. australis wetlands has experienced a great improvement after several years' restoration, and it is feasible to restored degraded P. australis wetlands by pouring fresh water into those wetlands in the Yellow River Delta. However, it is notable that costal degraded P. australis wetland in this region may take years to decades to reach the status of natural wetland. PMID:21968874
Wang, Xuehong; Yu, Junbao; Zhou, Di; Dong, Hongfang; Li, Yunzhao; Lin, Qianxin; Guan, Bo; Wang, Yongli
In this study, we compared ecological characteristics of wetland vegetation in a series of restoration projects that were carried out in the wetlands of Yellow River Delta. The investigated characteristics include plant composition structure, species diversity and community similarity in three kinds of Phragmites australis wetlands, i.e. restored P. australis wetlands (R1, R2, R3 and R4: restored in 2002, 2005, 2007 and 2009, respectively), natural P. australis wetland (N) and degraded P. australis wetland (D) to assess the process of wetlands restoration. The coverage of the R1 was 99%, which was similar to natural wetland. Among all studied wetlands, the highest and lowest stem density was observed in R1 and R2, respectively, Plant height and stem diameter show the same trend as N > R2 > R1 > R3 > D > R4. Species diversity of restored P. australis wetlands became closed to natural wetland. Both species richness and Shannon-Wiener index had similar tendency: increased first and then decreased with restored time. The highest species richness and species diversity were observed in R2, while the lowest values of those parameters were found in natural P. australis wetland. Similarity indexes between restored wetlands and natural wetland increased with the restoration time, but they were still less than 50%. The results indicate that the vegetation of P. australis wetlands has experienced a great improvement after several years' restoration, and it is feasible to restored degraded P. australis wetlands by pouring fresh water into those wetlands in the Yellow River Delta. However, it is notable that costal degraded P. australis wetland in this region may take years to decades to reach the status of natural wetland.
Wang, Xuehong; Yu, Junbao; Zhou, Di; Dong, Hongfang; Li, Yunzhao; Lin, Qianxin; Guan, Bo; Wang, Yongli
Full Text Available The present study follows an ecological demarch of reintegration in the scenary through revegetation of an anthropic ground, consisting in a waste pond formed from the flotation activity of non-ferrous ores. Problem statement: To support the formation of a compact vegetal layer, having an anti-errosion and a restoration role, a preliminary study was required regarding the spontaneous settlement of different vegetal species. We have followed the specific floristic composition and the biodiversity on the waste pond, the manner of association of plant species, and the possible interractions with other species from the biocenosis (microorganisms and fungi. We have also studied the pace at which vegetal species settle, as well as the reciprocal influence, from the point of view of vegetation, with the neighbouring area, since the desideratum is the settlement of a vegetation similar to the natural one. Approach: The aim of the research is to draw a list of the vegetal taxa installed on the pond, as well as to detect some succession stages or some possible vegetal associations. We have established the share of different species in the vegetal layer on the waste pond through an analysis of the ecological preferences, of the geographical origin of plant species, of the cariological and bioform profile. All this was done to compare the possible vegetal associations which settle on such anthropic grounds with the neighbouring vegetation. The approach used was the classical one in fitosociology, recommended by the Central European Fitosociological School adapted to the pedo-climatic conditions in Romania. Results: Over 50 species of plants and fungi spontaniously settled have been listed, and we have followed their association as well as their distribution, compared to the microclimatical conditions of the waste pond. In this way,we have distinguished species with a large potential of revegetating highly polluted with heavy metals waste ponds and sites. Conclusions/Recommendations: Starting from this study, we may establish a formula of sustaining the vegetation and using the interractions among species in order to stimulate the settlement of a dense vegetation which might ensure anti-errosion protection and landscape integration.
An investigation was conducted on the characteristics of soil nematode communities in different vegetation belts (Spartina alterniflora belt, Sa; Suaeda glauca belt, Sg; bare land, B1; Phragmites australis belt, Pa; and wheat land, Wl) of Yancheng Wetland Reserve, Jiangsu Province of East China. A total of 39 genera and 20 families of soil nematodes were identified, and the individuals of dominant genera and common genera occupied more than 90% of the total. The total number of the nematodes differed remarkably with vegetation belts, ranged from 79 to 449 individuals per 100 grams of dry soil. Wheat land had the highest number of soil nematodes, while bare land had the lowest one. The nematode ecological indices responded differently to the vegetation belts. The Shannon index (H) and evenness index (J) decreased in the order of Pa > Sg > Wl > Sa > Bl, and the dominance index (lambda) was in the order of Bl > Sa > Wl > Sg > Pa, suggesting that the diversity and stability of the nematode community in bare land were lower than those in the other vegetation belts, and the nematode community in the bare land tended to be simplified. The maturity index (MI) was higher in uncultivated vegetation belts than in wheat land, suggesting that the wheat land was disturbed obviously. The nematode community structure differed significantly with vegetation belts, and the main contributing species in different vegetation belts also differed. There existed significant correlations between the soil physical and chemical characteristics and the nematode numbers, trophic groups, and ecological indices. Our results demonstrated that the changes of soil nematode community structure could be used as an indicator well reflecting the diversity of vegetation belt habitat, and an important bio-indicator of coastal wetland ecosystem. PMID:23431791
Liu, Bei-Bei; Ye, Cheng-Long; Yu, Li; Jiao, Jia-Guo; Liu, Man-Qiang; Hu, Feng; Li, Hui-Xin
Long-distance pipeline construction results in marked human disturbance of the regional ecosystem and brings into question the safety of pipeline construction with respect to the environment. Thus, the direct environmental impact and proper handling of such large projects have received much attention. The potential environmental effects, however, have not been fully addressed, particularly for large linear pipeline projects, and the threshold of such effects is unclear. In this study, two typical eco-fragile areas in western China, where large linear construction projects have been conducted, were chosen as the case study areas. Soil quality indices (SQI) and vegetation indices (VI), representing the most important potential effects, were used to analyze the scope of the effect of large pipeline construction on the surrounding environment. These two indices in different buffer zones along the pipeline were compared against the background values. The analysis resulted in three main findings. First, pipeline construction continues to influence the nearby eco-environment even after a 4-year recovery period. During this period, the effect on vegetation due to pipeline construction reaches 300 m beyond the working area, and is much larger in distance than the effect on soil, which is mainly confined to within 30 m either side of the pipeline, indicating that vegetation is more sensitive than soil to this type of human disturbance. However, the effect may not reach beyond 500 m from the pipeline. Second, the scope of the effect in terms of distance on vegetation may also be determined by the frequency of disturbance and the intensity of the pipeline construction. The greater the number of pipelines in an area, the higher the construction intensity and the more frequent the disturbance. Frequent disturbance may expand the effect on vegetation on both sides of the pipeline, but not on soil quality. Third, the construction may eliminate the stable, resident plant community. During the recovery period, the plant community in the work area of the pipeline is replaced by some species that are rare or uncommon in the resident plant community because of human disturbance, thereby increasing the plant diversity in the work area. In terms of plant succession, the duration of the recovery period has a direct effect on the composition and structure of the plant community. The findings provide a theoretical basis and scientific foundation for improving the environmental impact assessment (EIA) of oil and gas pipeline construction as it pertains to the desert steppe ecosystem, and provide a reference point for recovery and management of the eco-environment during the pipeline construction period. PMID:25112841
Xiao, Jun; Wang, Ya-Feng; Shi, Peng; Yang, Lei; Chen, Li-Ding
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. PMID:21277663
Ochoa-Hueso, Raúl; Allen, Edith B; Branquinho, Cristina; Cruz, Cristina; Dias, Teresa; Fenn, Mark E; Manrique, Esteban; Pérez-Corona, M Esther; Sheppard, Lucy J; Stock, William D
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: email@example.com [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)
Full Text Available Normal 0 false false false MicrosoftInternetExplorer4 Expanding the range of bakery products in terms of producing supplemented or dietetic products has been an increasingly important trend in contemporary baking. Bakery products as basic and popular food, could be used in the prevention of nutritive deficiencies of many important nutrients, by supplementing the products with biologically valuable ingredients. Such ingredients are dehydrated vegetables in the form of powder. For establishing the bread quality, a special importance shows it’s chemical composition, because the substances that enter in it’s constitution serve to obtaining the energy necessary to the human body. Beside the chemical composition, the bread quality and alimentary use, respectively, depends a large measure on a series of signs: flavor and taste, external appearance, crumb porosity and texture, breads’ volume. This paper belongs to a more complex study, which aims are obtaining some bread assortments with high nutritional value, and improving their sensorial and rheological features, by adding dehydrated vegetables at different levels 4% potato flakes, 2% dehydrated onion, 0.5% dehydrated garlic and 2% dehydrated leek.
Full text: Full text: There is now ample evidence demonstrating the impacts of climate change on biodiversity and human society (Walther ef a/. 2002). Numerous studies have shown climate change is one of the most significant threats to tropical forests, such as the Wet Tropics Heritage Area, due to their high biodiversity and endemism (Pounds ef al. 1999; Hughes 2000; Parmesan and Yohe 2003). Williams ef al. (2003) suggested that small shifts in net primary productivity (NPP) as a result of climate change could lead to potentially massive follow-on effects for the extremely diverse and vulnerable rainforest flora and fauna. It is therefore crucial to explore the relationships between NPP and local biodiversity, especially to create models for different climate change scenarios. Nevertheless, NPP in the Wet Tropics has yet to be estimated. This is the first study to provide a general NPP estimate for the Wet Tropics bioregion using climate surrogates (Schuur 2003). This technique estimates NPP in an accurate, repeatable, and cost-effective way. NPP values were linked to vegetation types and examined under various climatic and environmental conditions. Results show a significant difference in productivity according to vegetation types and climatic variables, with temperature and rainfall seasonality as the most important determining variables. Additionally, lowland and upland vegetations showed a significant difference in productivity patterns throughout the year. Vegettivity patterns throughout the year. Vegetation types located above 1000 metres in altitude had the lowest values of mean annual productivity due to their high rainfall and low temperatures; vegetation types located below 600 metres showed increased productivity values during the wet season (December-March). Net primary productivity will certainly be impacted by changes in temperature and rainfall, due to climate change. Although an increase in NPP values can be predicted for upland areas, the more widely distributed lowlands will drastically decrease their productivity values. Information regarding the variability of net primary productivity across the Wet Tropics bioregion and its possible modifications due to climate change is crucial for management of future scenarios. The results from this study will help management agencies and conservation groups to plan accordingly
The book turns to the freshment, the teacher, for preparation of ecological topics for lessons, but also to pupils of the secondary stage II, and the main course ecology. The book was knowingly held simple with the restriction to: the ecosystem and its abiotic basic functions, simple articles on population biology, bioceonotic balance ith the questions of niche formation and the life form types coherent with it, of the substance and energy household, the production biology and space-wise and time-wise differentations within an ecological system form the main points. A central role in the volume is given to the illustrations. Their variety is to show and deepen the coherences shown. (orig./HP)
The ability of alien plant species to invade a region depends not only on attributes of the plant, but on characteristics of the habitat being invaded. Here, we examine characteristics that may influence the success of alien plant invasion in mixed-grass prairie at Theodore Roosevelt National Park, in western North Dakota, USA. The park consists of two geographically separate units with similar vegetation types and management history, which allowed us to examine the effects of native vegetation type, anthropogenic disturbance, and the separate park units on the invasion of native plant communities by alien plant species common to counties surrounding both park units. If matters of chance related to availability of propagules and transient establishment opportunities determine the success of invasion, park unit and anthropogenic disturbance should better explain the variation in alien plant frequency. If invasibility is more strongly related to biotic or physical characteristics of the native plant communities, models of alien plant occurrence should include vegetation type as an explanatory variable. We examined >1300 transects across all vegetation types in both units of the park. Akaike's Information Criterion (AIC) indicated that the fully parameterized model, including the interaction among vegetation type, disturbance, and park unit, best described the distribution of both total number of alien plants per transect and frequency of alien plants on transects where they occurred. Although all vegetation types were invaded by alien plants, mesic communities had both greater numbers and higher frequencies of alien plants than did drier communities. A strong element of stochasticity, reflected in differences in frequencies of individual species between the two park units, suggests that prediction of risk of invasion will always involve uncertainty. In addition, despite well-documented associations between anthropogenic disturbance and alien plant invasion, five of the six most abundant alien species at Theodore Roosevelt National Park had distributions unrelated to disturbance. We recommend that vegetation type be explicitly taken into account when designing monitoring plans for alien species in natural areas.
Larson, D.L.; Anderson, P.J.; Newton, W.
Full Text Available El desierto Chihuahuense (DC), el más grande del Continente Americano, está flanqueado por montañas que impiden el paso de los vientos húmedos: la Sierra Madre Oriental, la Faja Volcánica Trans-mexicana y la Sierra Madre Occidental (en México) y Las Rocallosas (en Estados Unidos); cubre una superfic [...] ie de 507,000 km², desde Nuevo México y Texas en Estados Unidos, hasta porciones de los estados de Chihuahua, Coahuila, Durango, Guanajuato, Hidalgo, Nuevo León, Querétaro, San Luis Potosí, Tamaulipas y Zacatecas, en México. El trabajo en campo consistió en la caracterización cualitativa de los principales tipos de vegetación del DC, con base en su fisonomía y en la recolección de ejemplares vegetales para su posterior identificación. Con los datos de composición y fisonomía se elaboraron perfiles semirrealistas de las principales asociaciones vegetales y de las condiciones fisiográficas y edáficas donde se desarrollaban. Las asociaciones detectadas fueron: matorral micrófilo de Larrea tridentata, matorral rosetófilo de Agave lechuguilla, matorral rosetófilo de Dasylirion spp., pastizal, chaparral, nopalera, mezquital, izotal, vegetación de dunas y vegetación halófita. Abstract in english The Chihuahuan Desert (CD), the largest in the Americas, is flanked by mountains that prevent wet winds from blowing across it; those mountain ranges are the Sierra Madre Oriental, the Trans-Mexican Volcanic Belt and the Sierra Madre Occidental in Mexico, and the Rockies in the United States. The de [...] sert covers an area of 507,000 km2, stretching from New Mexico and Texas in the United States to parts of the states of Chihuahua, Coahuila, Durango, Guanajuato, Hidalgo, Nuevo León, Querétaro, San Luis Potosi, Tamaulipas and Zacatecas in Mexico. Field work consisted of the qualitative characterization of the main vegetation types in the CH, based on their physiognomy and the collection of plant specimens for later identification. With the composition and physiognomy data, semi-realistic profiles were made of the main plant associations and the physiographic and soil conditions where they thrive. The associations detected were: Larrea tridentata microphyll scrub, Agave lechuguilla rosette scrub, Dasylirion spp. rosette scrub, grassland, chaparral, nopalera (a patch of prickly pears), mesquite, yucca, dune vegetation and halophytic vegetation.
Diódoro, Granados-Sánchez; Arturo, Sánchez-González; Ro Linnx, Granados Victorino; Amparo, Borja de la Rosa.
The natural vegetation and spoils of two abandoned, unreclaimed coal mines in the Mountain Park area were studied quantitatively in 34 stands. After 26 years of abandonment the vegetation of both Townsite and West Mine was sparse. Total plant cover was usually less than 10% and isolated plants were common. The communities were dominated by perennial grasses and forbs. Seven plant community types were recognized: (i) Festuca rubra - Epilobium angustifolium, (ii) Agropyron latiglume - Agropyron repens, and (iii) Agropyron spp. - Artemisia borealis on the Townsite; and (iv) Equisetum arvense - Potentilla fruticosa, (v) Agoseris glauca - Crepis nana, (vi) Agropyron latiglume - Crepis elegans, and (vii) Crepis nana - Eriogonum androsaceum on the West Mine. The spoil materials were generally coarse textured and structureless, consisting of rock fragments and loose single grains. Spoil samples were analysed for 20 physical and chemical properties. Variation in spoil properties appeared to strongly influence plant distribution and community development. Total plant cover and species richness were correlated with several spoil properties; highest correlations were with fine earth content (less than 2 mm) and clay content on the Townsite and West Mine sites, respectively. Slope position strongly influenced plant distribution on both study sites. Total plant cover, species richness, and the frequency of most species were highest at the slope base and lowest at the upper slope, midslope, and (or) crest positions. The sites were only 1.2 km apart, differed only 30 m in elevation, and were abandoned for the same length of time. Nevertheless, they differed edaphically and supported significantly different plant communities. 41 references.
Russell, W.B.; La Roi, G.M.
The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone) gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of veget...
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.
The ecological water conveyance project (EWCP) in the lower reaches of the Tarim River provided a valuable opportunity to study hydro-ecological processes of desert riparian vegetation. Ecological effects of the EWCP were assessed at large spatial and temporal scales based on 13 years of monitoring data. This study analyzed the trends in hydrological processes and the ecological effects of the EWCP. The EWCP resulted in increased groundwater storage-expressed as a general rise in the groundwater table-and improved soil moisture conditions. The change of water conditions also directly affected vegetative cover and the phenology of herbs, trees, and shrubs. Vegetative cover of herbs was most closely correlated to groundwater depth at the last year-end (R?=?0.81), and trees and shrubs were most closely correlated to annual average groundwater depth (R?=?0.79 and 0.66, respectively). The Normalized Difference Vegetation Index (NDVI) responded to groundwater depth on a 1-year time lag. Although the EWCP improved the NDVI, the study area is still sparsely vegetated. The main limitation of the EWCP is that it can only preserve the survival of existing vegetation, but it does not effectively promote the reproduction and regeneration of natural vegetation. PMID:25074365
Hao, Xingming; Li, Weihong
High altitude color and multispectral black and white photography was used to survey existing vegetation and soil conditions on the Empire Ranch where large scale development will soon begin. Utilizing stereo pairs of the high altitude color photography, four vegetation classifications were discernable as a function of topography and foliage characteristics. In contrast to the undeveloped Ranch, the same photography was used to detect environmental changes in the Tucson metropolitan area as a result of rapid urbanization. The most prevalent change related to development is the removal of vegetation in high density areas to allow for housing starts. Erosion then occurs where vegetation has been removed.
Foster, K.; Garcia, A.
Non-vascular plants (lichens and mosses) are significant components of tundra landscapes and may respond to climate change differently from vascular plants affecting ecosystem carbon balance. Remote sensing provides critical tools for monitoring plant cover types, as optical signals provide a way to scale from plot measurements to regional estimates of biophysical properties, for which spatial-temporal patterns may be analyzed. Gas exchange measurements were collected for pure patches of key vegetation functional types (lichens, mosses, and vascular plants) in sedge tundra at Barrow, AK. These functional types were found to have three significantly different values of light use efficiency (LUE) with values of 0.013 plus or minus 0.0002, 0.0018 plus or minus 0.0002, and 0.0012 plus or minus 0.0001 mol C mol (exp -1) absorbed quanta for vascular plants, mosses and lichens, respectively. Discriminant analysis of the spectra reflectance of these patches identified five spectral bands that separated each of these vegetation functional types as well as nongreen material (bare soil, standing water, and dead leaves). These results were tested along a 100 m transect where midsummer spectral reflectance and vegetation coverage were measured at one meter intervals. Along the transect, area-averaged canopy LUE estimated from coverage fractions of the three functional types varied widely, even over short distances. The patch-level statistical discriminant functions applied to in situ hyperspectral reflectance data collected along the transect successfully unmixed cover fractions of the vegetation functional types. The unmixing functions, developed from the transect data, were applied to 30 m spatial resolution Earth Observing-1 Hyperion imaging spectrometer data to examine variability in distribution of the vegetation functional types for an area near Barrow, AK. Spatial variability of LUE was derived from the observed functional type distributions. Across this landscape, a fivefold variation in tundra LUE was observed. LUE calculated from the functional type cover fractions was also correlated to a spectral vegetation index developed to detect vegetation chlorophyll content. The concurrence of these alternate methods suggest that hyperspectral remote sensing can distinguish functionally distinct vegetation types and can be used to develop regional estimates of photosynthetic LUE in tundra landscapes.
Huemmrich, Karl Fred; Gamon, John A.; Tweedie, Craig E.; Campbell, Petya K. Entcheva; Landis, David R.; Middleton, Elizabeth M.
In developing conservation strategies, it is important to maximize effects of conservation within a specified land tract and to maximize conservation effects on surrounding area (ecological context). The authors proposed two criteria to select biotic entities for conservation foci: (1) the relative occurrence of fauna or flora in a tract is greater than that of an ecological context region; and (2) occurrence of the fauna or flora is relatively limited in the ecological context region. Using extensive spatial data on vegetation and wildlife habitat distribution, the authors identified strategic vegetation and fauna conservation foci for the 400 000 ha Fort Bliss military reservation in New Mexico and Texas relative to a 164 km radius ecological context region intersecting seven ecological zones and the predicted habitat distribution of 616 animal species. The authors set two specific criteria: (1) predicted area of a species' occurrence is 5% (Fort Bliss is 4.2% of the region). These criteria selected one vegetation class and 40 animal species. Further, these vegetation and animal foci were primarily located in two areas of Fort Bliss. Sensitivity analyses with other analytical radii corroborated the context radius used. Conservation of the two areas and associated taxa will maximize the contribution of Fort Bliss's conservation efforts in its ecological proximity. This relatively simple but information-rich process represents economical and defensible preliminary contextual analysis for detailed conservation planning.
Hamazaki, T.; Thompson, B.C.; Locke, B.A.; Boykin, K.G.
Cutting-edge remote sensing technology has a significant role for managing the natural resources as well as the any other applications about the earth observation. Crop monitoring is the one of these applications since remote sensing provides us accurate, up-to-date and cost-effective information about the crop types at the different temporal and spatial resolution. In this study, the potential use of three different vegetation indices of RapidEye imagery on crop type classification as well as the effect of each indices on classification accuracy were investigated. The Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), and the Normalized Difference Red Edge Index (NDRE) are the three vegetation indices used in this study since all of these incorporated the near-infrared (NIR) band. RapidEye imagery is highly demanded and preferred for agricultural and forestry applications since it has red-edge and NIR bands. The study area is located in Aegean region of Turkey. Radial Basis Function (RBF) kernel was used here for the Support Vector Machines (SVMs) classification. Original bands of RapidEye imagery were excluded and classification was performed with only three vegetation indices. The contribution of each indices on image classification accuracy was also tested with single band classification. Highest classification accuracy of 87, 46 % was obtained using three vegetation indices. This obtained classification accuracy is higher than the classification accuracy of any dual-combination of these vegetation indices. Results demonstrate that NDRE has the highest contribution on classification accuracy compared to the other vegetation indices and the RapidEye imagery can get satisfactory results of classification accuracy without original bands.
Ustuner, M.; Sanli, F. B.; Abdikan, S.; Esetlili, M. T.; Kurucu, Y.
Dynamic global vegetation models (DGVMs) are powerful tools to project past, current and future vegetation patterns and associated biogeochemical cycles. However, most models are limited by how they define vegetation and by their simplistic representation of competition. We discuss how concepts from community assembly theory and coexistence theory can help to improve vegetation models. We further present a trait- and individual-based vegetation model (aDGVM2) that allows individual plants to adopt a unique combination of trait values. These traits define how individual plants grow and compete. 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 a site's biotic and abiotic conditions. The aDGVM2 simulates how environmental conditions influence the trait spectra of plant communities; that fire selects for traits that enhance fire protection and reduces trait diversity; and the emergence of life-history strategies that are suggestive of colonization-competition trade-offs. The aDGVM2 deals with functional diversity and competition fundamentally differently from current DGVMs. This approach may yield novel insights as to how vegetation may respond to climate change and we believe it could foster collaborations between functional plant biologists and vegetation modellers. PMID:23496172
Scheiter, Simon; Langan, Liam; Higgins, Steven I
A dynamic food chain model has been built for the modeling of the transfer of 137Cs in three types of vegetables consumed in Hong Kong, namely, white flowering cabbage (Brassica chinensis), head lettuce (Lactuca sativa) and celery (Apium graveolens). Some parameters have been estimated from the experimental data obtained in this work. The experimental data include the transfer factors of 137Cs from soil to the different vegetable species which are determined through high resolution gamma spectrometry, maximum crop biomasses for the vegetable species, the dry-to-fresh ratios for the vegetable species, the bulk density of soil layers and the average concentration of 137Cs in air. The derived parameters include the deposition rate and the root uptake rate, information for tillage, the logistic growth model and radionuclide concentrations in vegetables. The dynamic food chain model is solved by the Birchall-James algorithm to give the 137Cs concentration in subsurface soil, from the 0.1-25 cm soil layer, and the 137Cs concentration in harvested and unwashed vegetables. As validation of the model and parameters, the concentrations obtained experimentally and from the model are compared and are found to be in good agreement
In this paper, the stationary probability distribution (SPD) and mean first passage time (MFPT) in a vegetation model with time delay are investigated, where the vegetation dynamics is assumed to be disturbed by both intrinsic and extrinsic noises. The impacts of the intrinsic noise strength ?, extrinsic noise strength D, time delay ? and cross-correlation strength q between two noises on the SPD and MFPT of the regime shifts between the sustainable vegetation and barren states are discussed, respectively. Our main results are as follows. (i) The increase of ? will cause regime shifts from the barren state to the sustainable vegetation state, while the increase of D or ? will cause regime shifts from the sustainable vegetation state to the barren state. (ii) The MFPT as a function of the noise intensities (i.e., ? and D) exhibits one maximum value in the case of q 0.0), the presence of time delay can also cause the existence of extrinsic noise enhanced stability. (paper)
SACRIFICING THE ECOLOGICAL RESOLUTION OF VEGETATION MAPS AT THE ALTAR OF THEMATIC ACCURACY: ASSESSED MAP ACCURACIES FOR HIERARCHICAL VEGETATION CLASSIFICATIONS IN THE EASTERN GREAT BASIN OF THE SOUTHWEST REGIONAL GAP ANALYSIS PROJECT (SW REGAP)
The Southwest Regional Gap Analysis Project (SW ReGAP) improves upon previous GAP projects conducted in Arizona, Colorado, Nevada, New Mexico, and Utah to provide a consistent, seamless vegetation map for this large and ecologically diverse geographic region. Nevada's compone...
Even if mires have proven to be relatively reliable archives over the temporal trends in atmospheric mercury deposition, there are large discrepancies between sites regarding the magnitude of the anthropogenic contribution to the global mercury cycle. A number of studies have also revealed significant differences in mercury accumulation within the same mire area. This raises the question of which factors, other than mercury deposition, affect the sequestration of this element in peat. One such factor could be vegetation type, which has the potential to affect both interception and retention of mercury. In order to assess how small-scale differences in vegetation type can affect mercury sequestration we sampled peat and living plants along three transects on a northern Swedish mire. The mire has two distinctly different vegetation types, the central part consists of an open area dominated by Sphagnum whereas the surrounding fen, in addition to Sphagnum mosses, has an understory of ericaceous shrubs and a sparse pine cover. A few main patterns can be observed in our data; (1) Both peat and Sphagnum-mosses have higher mercury content (both concentration and inventory) in the pine-covered fen compared to the open Sphagnum area (100% and 71% higher for peat and plants, respectively). These differences clearly exceed the 33% difference observed for lead-210, which is considered as a good analogue for atmospheric mercury deposition. (2) The differences in mercury concentration between peat profiles within a single vegetation type can largely be attributed to differences in peat decomposition. (3) When growing side by side in the open Sphagnum area, the moss species Sphagnum subsecundum has significantly higher mercury concentrations compared to S. centrale (24 ± 3 and 18 ± 2 ng Hg g -1, respectively). Based on these observations we suggest that species composition, vegetation type and decomposition can affect the mercury sequestration in a peat record, and that any changes in these properties over time, or space, have the potential to modify the mercury deposition signal recorded in the peat.
Rydberg, Johan; Karlsson, Jon; Nyman, Roger; Wanhatalo, Ida; Näthe, Kerstin; Bindler, Richard
As a description of altitude-belt zonality of wood vegetation, a model of ecological second-order transitions is proposed. Objects of the study have been chosen to be forest cenoses of the northern slope of Kulumyss Ridge (the Sayan Mauntains), while the results are comprised by the altitude profiles of wood vegetation. An ecological phase transition can be considered as the transition of cenoses at different altitudes from the state of presence of certain tree species within the studied territory to the state of their absence. By analogy with the physical model of second-order, phase transitions the order parameter is introduced (i.e., the area portion occupied by a single tree species at the certain altitude) as well as the control variable (i.e., the altitude of the wood vegetation belt). As the formal relation between them, an analog of the Landau's equation for phase transitions in physical systems is obtained. It is shown that the model is in a good accordance with the empirical data. Thus, the model can be used for estimation of upper and lower boundaries of altitude belts for individual tree species (like birch, aspen, Siberian fir, Siberian pine) as well as the breadth of their ecological niches with regard to altitude. The model includes also the parameters that describe numerically the interactions between different species of wood vegetation. The approach versatility allows to simplify description and modeling of wood vegetation altitude zonality, and enables assessment of vegetation cenoses response to climatic changes. PMID:25508927
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 differenotential factors driving regional differences are discussed.
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: firstname.lastname@example.org [Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540 (United States)
Ro?. 118, ?. 1 (2009), s. 122-130. ISSN 0030-1299 R&D Projects: GA AV ?R IAA100070601 Grant 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) REN2003-00273 Institutional research plan: CEZ:AV0Z50070508 Keywords : complex ecological network Subject RIV: EH - Ecology, Behaviour Impact factor: 3.147, year: 2009
Melián, C. J.; Bascompte, J.; Jordano, P.; K?ivan, Vlastimil
Climate change in tundra regions may alter vegetation species composition and ecosystem carbon balance, and remote sensing provides critical tools for monitoring these changes. Measurements of pure patches of key plant functional types (lichens, mosses, and vascular plants) in sedge tundra at Barrow AK, show three different values of light use efficiency (LUE). Also, discriminant analysis of patch reflectance identifies seven spectral bands that can separate each functional type and nongreen material (bare soil and dead leaves). These results were tested along a 100 m transect across the tundra. At every meter, midsummer spectral reflectance and vegetation coverage were measured. LUE estimated from coverage fractions varies widely, even over short distances. The patch-level discriminant functions successfully unmixed cover fractions of the functional types, with standard errors well within the expected measurement error of the coverage. These results demonstrate the use of hyperspectral remote sensing to provide direct estimates of tundra ecosystem LUE variability.
Huemmrich, K. F.; Gamon, J. A.; Tweedie, C. E.
The object of our study was 5.3 km long stretch of the river Rimavica with its adjacent ecosystems. The research results show that most of the observed vegetation fulfill its function well in the country. Only certain sections require more human care, in order to strengthen their positive impact on the flow of water and other components of the ecosystem. (authors)
Mapping accurately vegetation type is one of the main challenges for monitoring arid and semi-arid grasslands with remote sensing. The multi-angle approach has been demonstrated to be useful for mapping vegetation types in deserts. This letter presents a study on the use of directional reflectance d...
Re-vegetation of trace element contaminated soils can alter the pH and chelating capacity in the rhizosphere, increasing the mobility of pollutants, which, in turn, may impact on rhizosphere ecology. In this study a short-term pot experiment was carried out in order to investigate the multi-factorial effects of: buffering capacity (sandy-loam and loam soils); pollutant load (0%, 1.3%, and 4% of pyrite sludge), and the presence/absence of plant (Lolium perenne L. and Medicago sativa L.) on the mobility of trace elements, soil biochemical functionality (hydrolase activities), and biological diversity (bacterial and nematode communities). The experiment was carried out with representative soils from the Guadiamar basin (SW Spain), an area where the Aznalcóllar mining spill affected over 4000ha. Results indicated that the development of rhizospheres in polluted soils (coarse-textured) increases the mobilization of trace elements. In general the presence of roots has stimulatory effects on soil quality indicators such as hydrolase activities and both bacterial and nematode communities. However, the presence of high amount of metals interferes with these beneficial effects. This study provided evidence about the complexity of the impact of growing plants on trace element polluted soils. Trace element mobilization, hydrolase activities and bacterial and nematode communities in the rhizosphere are dependent on plant species, soil type, and pollution dose. PMID:20385407
Belén Hinojosa, M; Carreira, José A; García-Ruíz, Roberto; Rodríguez-Maroto, José M; Daniell, Tim J; Griffiths, Bryan S
Since the 1980s, the coastal wetlands in Korea have been rapidly degraded and destroyed mainly due to reclamation and landfills for coastal development. In order to recover damaged coastal environments and to develop wetland restoration technologies, a 4-year study on ecological the restoration of coastal vegetated ecosystems was started in 1998. As one of a series of studies, a small-scale experiment on salt marsh restoration was carried out from April 2000 to August 2001. The experiment was designed to find effective means of ecological restoration through a comparison of the changes in environmental components and species structure between two different experimental plots created using sediment fences, one with and one without small canals. Temporal variation in surface elevation, sedimentary facies, and benthic species were measured seasonally in each plot and in the adjacent natural reference sites. Monthly exposure occurred from 330 cm to mean sea level, which represents the critical tidal level (CTL) at which salt marsh plants colonize. Vegetation, especially Suaeda japonica, colonized the site the following spring and recovered to a similar extent in the natural marshes 16 months later. The sedimentary results indicated that the sediment fences had effects on particle size and sediment accumulation, especially in the plot with small canals. This experiment also showed that tidal height, especially that exceeding the CTL, is an important factor in the recovery of the benthic fauna of salt marshes. From these results, we suggested that designs for the restoration of salt marsh ecosystems must consider the inclusion of a tidal height exceeding CTL, as this may allow reconstruction of the previous natural ecosystem without artificial transplanting.
Koo, Bon Joo; Je, Jong Geel; Woo, Han Jun
Ecosystem entropy production is predicted to increase along ecological succession and approach a state of maximum entropy production, but few studies have bridged the gap between theory and data. Here, we explore radiative entropy production in terrestrial ecosystems using measurements from 64 Free/Fair-Use sites in the FLUXNET database, including a successional chronosequence in the Duke Forest in the southeastern United States. Ecosystem radiative entropy production increased then decreased...
Stoy, Paul C.; Hua Lin; Novick, Kimberly A.; Siqueira, Mario B. S.; Jehn-Yih Juang
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 topsoi...
Rivera, Desire?e; Meji?as, Violeta; Ja?uregui, Berta M.; Costa-tenorio, Marga; Lo?pez-archilla, Ana Isabel; Peco, Begon?a
Most research on boundaries between vegetation types emphasizes the contrasts and similarities between conditions on either side of a boundary, but does not compare boundary to non-boundary vegetation. That is, most previous studies lack suitable controls, and may therefore overlook underlying aspects of landscape variability at a regional scale and underestimate the effects that the vegetation itself has on the soil. We compared 25 soil chemistry variables in rainforest, sclerophyll vegetati...
Warman, Laura; Bradford, Matt G.; Moles, Angela T.
Drought and shortages of soil water are becoming extremely severe due to global climate change. A better understanding of the relationship between vegetation type and soil-moisture conditions is crucial for conserving soil water in forests and for maintaining a favorable hydrological balance in semiarid areas, such as the Saihanwula National Nature Reserve in Inner Mongolia, China. We investigated the temporal dynamics of soil moisture in this reserve to a depth of 40 cm under three types of vegetation during a period of rainwater recharge. Rainwater from most rainfalls recharged the soil water poorly below 40 cm, and the rainfall threshold for increasing the moisture content of surface soil for the three vegetations was in the order: artificial Larix spp. (AL) > Quercus mongolica (QM) > unused grassland (UG). QM had the highest mean soil moisture content (21.13%) during the monitoring period, followed by UG (16.52%) and AL (14.55%); and the lowest coefficient of variation (CV 9.6-12.5%), followed by UG (CV 10.9-18.7%) and AL (CV 13.9-21.0%). QM soil had a higher nutrient content and higher soil porosities, which were likely responsible for the higher ability of this cover to retain soil water. The relatively smaller QM trees were able to maintain soil moisture better in the study area. PMID:25781333
Zheng, Hao; Gao, Jixi; Teng, Yanguo; Feng, Chaoyang; Tian, Meirong
This study evaluated the feasibility of methane production from fruit and vegetable waste (FVW) obtained from the central food distribution market in Mexico City using an anaerobic digestion (AD) process. Batch systems showed that pH control and nitrogen addition had significant effects on biogas production, methane yield, and volatile solids (VS) removal from the FVW (0.42 m(biogas)(3)/kg VS, 50%, and 80%, respectively). Co-digestion of the FVW with meat residues (MR) enhanced the process performance and was also evaluated in a 30 L AD system. When the system reached stable operation, its methane yield was 0.25 (m(3)/kg TS), and the removal of the organic matter measured as the total chemical demand (tCOD) was 65%. The microbial population (general Bacteria and Archaea) in the 30 L system was also determined and characterized and was closely correlated with its potential function in the AD system. PMID:21865034
Garcia-Peña, E I; Parameswaran, P; Kang, D W; Canul-Chan, M; Krajmalnik-Brown, R
At Las Tres Virgenes, B.C.S., Mexico developed the Geothermic exploratory drilling of the area. One of the main recommendations of our Environmental Impact Assessment Study includes transplantation of the plant individuals found in the zones of roads and drilling platforms. In this work we describe the methodologies used to transplant the vegetal individuals found in such zones. We listed the species selected and the survivorship rate obtained for every one of them. From a total of 4,266 transplanted individuals, including many endemic species, a total of 2349 survived. Members of the Agavaceae and Cactaceae families show the maximum survivorship rate, meanwhile the members of the Burseraceae, Euphorbiaceae and Fouqueriaceae families exhibited the minimum survivorship rate (between 12.7% and 20%).
Ortega-Rubio, A.; Salinas, F.; Naranjo, A. [and others
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
Most research on boundaries between vegetation types emphasizes the contrasts and similarities between conditions on either side of a boundary, but does not compare boundary to non-boundary vegetation. That is, most previous studies lack suitable controls, and may therefore overlook underlying aspects of landscape variability at a regional scale and underestimate the effects that the vegetation itself has on the soil. We compared 25 soil chemistry variables in rainforest, sclerophyll vegetation and across rainforest-sclerophyll boundaries in north-eastern Queensland, Australia. Like previous studies, we did find some contrasts in soil chemistry across vegetation boundaries. However we did not find greater variation in chemical parameters across boundary transects than in transects set in either rainforest or woodland. We also found that soil on both sides of the boundary is more similar to "rainforest soil" than to "woodland soil". Transects in wet sclerophyll forests with increasing degrees of rainforest invasion showed that as rainforest invades wet sclerophyll forest, the soil beneath wet sclerophyll forest becomes increasingly similar to rainforest soil. Our results have implications for understanding regional vegetation dynamics. Considering soil-vegetation feedbacks and the differences between soil at boundaries and in non-boundary sites may hold clues to some of the processes that occur across and between vegetation types in a wide range of ecosystems. Finally, we suggest that including appropriate controls should become standard practice for studies of vegetation boundaries and edge effects worldwide. PMID:23593312
Warman, Laura; Bradford, Matt G; Moles, Angela T
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.
Since the 1990’s, there has been increasing scientific interest in investigating place effects on dietary and exercise behaviors. The two overall aims of this dissertation are designed to investigate at an area level and at an individual level, how food and physical activity resources are spatially distributed by socioeconomic indicators, and whether these associations can be observed between aspects of the built environment and: a) fruit and vegetable intake, and b) vigorous physical activity in individuals. Specifically, this involves operationalization of geographical measures of exposure within neighborhood environments, with development and validation of data used to describe characteristics of exercise and dietary resources. The concept of deprivation amplification is also investigated, which suggests that individual or household deprivation is further enhanced or comprised by the lack of resources in the neighborhood, and could manifest itself in poor health behaviors. This concept is first studied at the neighborhood level, by examining the socioeconomic patterning of food and exercise resources. Next, at the individual level, I examine the combined effects of socioeconomic status and the built environment, and report on how these associations affect individual dietary and exercise behavior. Data drawn for the individually-based analyses stem from the Danish contribution to the Health Behavior in School-aged Children Study (HBSC), an international, cross-sectional population-based study investigating the health and health behaviors of 11-to-15-year old school children. Outcome measures for these studies were infrequent less than daily intake of fruit and vegetables (Paper II) and frequent vigorous physical activity of one hour or more per day (Paper IV). The individual dataset was appended with a validated and cross-referenced objected database built for these studies and contained location information about supermarkets, fast food outlets, and various exercise-supportive resources (public open space, sports facilities, street connectivity, and total length of cycling and walking paths). The neighborhood-based analyses uses validated and cross-referenced objective data about food and physical activity resources in each of the 400 neighborhoods in Copenhagen and combines them with area-level socioeconomic and demographic data derived from The National Statistics Bank of Denmark. Outcome measures for these studies were also defined as the number of supermarkets and fast food outlets in each neighborhood (Paper I) and high exposure (top 25%) to resources supportive of physical activity. Study findings are expressed as either relative risk (RR) or odds ratios (OR), with 95% confidence intervals (CI). In general, study findings indicate no clear socioeconomic patterning of food or physical activity resources by examining neighborhood units alone. For example, there was no association between areal income and supermarket exposure in Copenhagen, while low income areas were more likely to be exposed to fewer fast food outlets than high-income neighborhoods (RR = 0.66; CI: 0.46-0.97). Areas with a high proportion of residents lacking a high school diploma had greater exposure to physical activity resources such as, public open space (OR = 1.90; CI: 1.15-3.15), cycling and walking paths (OR = 3.46; CI: 1.86-6.42) and one or more sports facilities (OR = 2.05; CI: 1.36-3.10) than the referent. Areas with high proportions of children were less likely to have exposure to connected streets (OR = 0.51; 0.31-0.83) than areas with low proportions of children. Results from individual-level studies generally show that while socioeconomic status remains an important individual predictor for diet and exercise behavior, the exposure to resources in the neighborhood environment may differentially affect children according to social class background. Children from low social class backgrounds attending schools with low exposure to supermarkets had the greatest odds of infrequent vegetable (OR = 1.50; CI: 1.03-2.20) and fruit (OR = 1.43
Aiming at the intrinsic relationships between vegetation type and soil salinity in coastal saline area, and by using electromagnetic induction EM38 and field sampling method, the characteristics of soil salinity profiles under various vegetation types in typical coastal saline region of the Yellow River Delta were analyzed, and the electromagnetic response characters of the salinity profiles were compared. The results showed that across the study area, soil salinity exhibited the characteristics of top enrichment and strong spatial variation. The horizontal electromagnetic conductivity EM(h) responded well to soil salinity at upper layers, and the response of vertical electromagnetic conductivity EM(v) to soil salinity at deeper layers was superior to that of EM(h). Soil salinity profiles were classified into inverted, normal, and uniform types. The vegetation types of inverted salinity profiles were mainly bare land and Suaeda salsa, while those of normal and uniform salinity profiles were cotton and weed, respectively. The sequence of top enrichment intensity was bare land > S. salsa land > weed land > cotton land. With the change of vegetation type of cotton-weed-S. salsa-bare land, the EM(v)/EM(h) value of salinity profiles decreased gradually. Nonparametric test results showed that there was a significant correlation between vegetation type and electromagnetic response characters, and the distribution characters of EM(v)/EM(h) under various vegetation types varied significantly. PMID:19123343
Yang, Jing-Song; Yao, Rong-Jiang; Zou, Ping; Liu, Guang-Ming
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
Vascular plants have been collected from abandoned or inactive uranium mill tailings in three mining areas in Canada. The collection was evaluated to determine some characteristics of vegetation development and to identify the plants which will persist on the sites. A total of 170 species were identified. Many of the species are widely distributed in North America, none has been reported as rare in any of the locations from which they were collected. Species richness was highest on Bancroft sites and lowest on Uranium City sites, though values were variable between sites. Forty-four per cent of the total number of species were found on only a single site. Only seven species occurred on more than half of the tailings sites and in all three mining areas. There was no difference between amended and unamended sites in terms of either species richness or species composition. There was no apparent relationship between species richness and either site size, site age or amendment history. The results of this survey suggest that the uranium mill tailings sites are at an early stage of colonization where the seed input from surrounding areas and the heterogeneity of the sites are factors determining species composition and species richness. The fate of an individual once it has reached the site will be determined by its ability to establish on the sites. A perennial growth habit and the ability to expand clonally are important characteristics of the species on the tailings. Theistics of the species on the tailings. The species on the tailings are commonly found in a variety of habitats. Consistent with the observation that the tailings sites are at a stage of early colonization, we find that the few species widely distributed across sites are all characteristic pioneering species with wide environmental tolerances. These species included Populus tremuloides, P. balsamifera, Scirpus cyperinus, Equisetum arvense, Betula papyrifera, Achillea millefolium and Typha spp. The vegetation on the tailings is likely to be characterized by these species for a long period of time. (author)
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.
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
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.
Theo H.C., Mostert; George J., Bredenkamp; Hannes L., Klopper; Cornie, Verwey; Rachel E., Mostert; Norbert, Hahn.
The Ent Dynamic Global Terrestrial Ecosystem Model (DGTEM), is a new DGTEM for coupling the fluxes of water, energy, carbon and nitrogen between land surface and climate models, for simulating seasonal growth and decay of vegetation, and for simulating decadal- to century-scale vegetation cover change. This study shows the use of Fluxnet data in evaluating vegetation phenology, carbon allocation, and growth in the Ent DGTEM in both stand-alone mode and coupled mode to GISS Land Surface Model (LSM), and the performance of the coupled model at the global scale forced by Global Soil Wetness Project-2 (GSWP2) meteorology. Ecosystem types modeled include temperature broadleaf cold-deciduous forest at Harvard Forest, MA, and Morgan Monroe State Forest, IN; drought-senescent Mediterranean oak/annual grass savanna at Tonzi Ranch, CA, and annual grassland at Vaira Ranch, CA; and radiation phenology of tropical rainforest in Tapajos National Forest, Brazil. Site-level simulations forced with Fluxnet meterological data are evaluated by comparing the simulated leaf area index (LAI), carbon stocks in plant carbon pools, and carbon and water fluxes between land and the atmosphere against observational data. Global-scale simulations forced with GSWP2 data for 1986 to 1995 are performed to answer the question of whether the model, well-constrained against the local observations over the limited number of years, extrapolates well to global scales and captures interannual variation over the course of 10 years.
Kim, Y.; Moorcroft, P. R.; Koster, R. D.; Kiang, N. Y.
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
Palmero cheese is a fresh smoked cheese from the Isle of Palma (Canary Islands), manufactured with goat's milk. To guarantee its safety, the occurrence of polycyclic aromatic hydrocarbons (PAH) in artisanal Palmero cheese smoked with 2 types of vegetable matter (almond shells and dry prickly pear) was studied. The determination of PAH includes extraction and clean-up steps, followed by separation, identification, and quantification of PAH by gas chromatography-mass spectrometry in selected ion-monitoring mode. The most abundant PAH are those with 2 and 3 aromatic rings. Although the highest total PAH concentrations corresponded to the cheeses smoked with almond shells, the degree of PAH contamination of the cheeses studied was lower than that found in other cheeses smoked in the traditional way. The nature of the vegetable material used for smoking seemed to have an influence on the type of PAH formed, especially on alkylderivatives and some light PAH. However, despite the artisanal, and consequently variable, production process of these cheeses, many similarities have been found among their PAH profiles. In fact, relatively constant relationships are observed between the concentrations of certain pairs of PAH. Benzo(a)pyrene was only present in 2 samples, and in much lower concentrations than the maximum allowed legal limits. Therefore, according to the results obtained, it appears that it is possible to obtain a safe product without renouncing the artisanal character or the sensory properties of this type of cheese. PMID:17517711
Guillén, M D; Palencia, G; Sopelana, P; Ibargoitia, M L
The shelf-life of the vegetable-type soybean pods stored under different conditions was evaluated by chemical characteristics and color. The pods were harvested in the R6 stage and stored either at 30 or 7ºC for 9 d. After the storage period, the pods were blanched and threshed, and the immature green grains were used for the analysis. The protein content decreased after 6 d of storage at 7ºC. There was no difference in the lipid content after the storage at 30 and 7ºC for 9 d. The starch ...
Andréia Cristina Santana; Mercedes Concórdia Carrão-Panizzi; José Marcos Gontijo Mandarino; Rodrigo Santos Leite; Josemeyre Bonifácio da Silva; Elza Iouko Ida
The browsing preference and ecological carrying capacity (ECC) of sambar deer (Cervus unicolor brookei) in acacia plantations for management and conservation of the ecosystem were investigated at Sabal Forest Reserve in Sarawak, Malaysia. The identification of the species browsed by the sambar deer was based on an observation of the plant parts consumed. ECC estimation was based on body weight (BW) and the physiological stages of animals browsed in six fenced 4-ha paddocks. Sambar deer were found foraging on only 29 out of 42 species of secondary vegetation in the acacia plantation. The remaining species are too high for the deer to reach. Planted species, Shorea macrophylla are not palatable to the deer. This augurs well for the integration of sambar deer into shorea plantations. The most frequently exploited plants were Ficus spp. Sambar deer preferred woody species more than non-woody species and they are browser animals. By producing metabolizable energy of 19,000 to 27,000 MJ/ha, the ECC was five head/ha to 5.25 head/ha. Given its contribution to the conservation of wildlife and its capacity to sustain the ecosystem, the sambar deer integrated farming system offers a promising strategy for the future of tropical forestry management. PMID:25163638
Ismail, Dahlan; Jiwan, Dawend
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
Identification and social-ecological characterization of areas that experience high levels of persistent productivity decline are essential for planning appropriate management measures. Although land degradation is mainly induced by human actions, the phenomenon is concurrently influenced by global climate changes that need to be taken into account in land degradation assessments. This study aims to delineate the geographic hotspots of human-induced land degradation in the country and classify the social-ecological characterizations of each specific degradation hotspot type. The research entailed a long-term time-series (1982-2006) of Normalized Difference Vegetation Index to specify the extents of areas with significant biomass decline or increase in Vietnam. Annual rainfall and temperature time-series were then used to separate areas of human-induced biomass productivity decline from those driven by climate dynamics. Next, spatial cluster analyses identified social-ecological types of degradation for guiding further investigations at regional and local scales. The results show that about 19% of the national land mass experienced persistent declines in biomass productivity over the last 25 years. Most of the degraded areas are found in the Southeast and Mekong River Delta (17,984 km2), Northwest Mountains (14,336 km2), and Central Highlands (13,504 km2). We identified six and five social-ecological types of degradation hotspots in agricultural and forested zones, respectively. Constraints in soil nutrient availability and nutrient retention capability are widely spreading in all degradation hotspot types. These hotspot types are different from each other in social and ecological conditions, suggesting that region-specific strategies are needed for the formulation of land degradation combating policy.
Vu, Quyet Manh; Le, Quang Bao; Vlek, Paul L. G.
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.
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.
Ecology is the study of interaction of living organisms in the environment. However the modern meaning of the concept of ecology has a wider meaning than in the early decades of the development of this science. Currently, most often under the mistaken environmental issues are understood, above all, the protection of the environment. In many ways, this shift is due to sense more tangible consequences of human impact on the environment. When you are citing the document, use the following lin...
There is increasing demand for reliable, high-resolution vegetation maps covering large areas. Airborne laser scanning data is available for large areas with high resolution and supports automatic processing, therefore, it is well suited for habitat mapping. Lowland hay meadows are widespread habitat types in European grasslands, and also have one of the highest species richness. The objective of this study was to test the applicability of airborne laser scanning for vegetation mapping of dif...
András Zlinszky; Anke Schroiff; Adam Kania; Balázs Deák; Werner Mücke; Ágnes Vári; Balázs Székely; Norbert Pfeifer
A land suitability study was carried out by applying a multiple-criteria technique to 12 different vegetation types in Mexico's Tamaulipas state to help select potentially suitable sites for hazardous waste treatment plants. Species richness, spatial distribution, and uniqueness were selected as the criteria for estimating a vegetation type's suitability. Using the analytical hierarchy process, we ranked and mapped vegetation types, then compared the results with rankings of the same vegetation types based only on their number of endemic species. The suitabilities of the various vegetation types were ordered in more or less the same way by both methods, except in two cases for which the results were very different. The method proved to be a useful tool despite the availability of only partial (mostly qualitative) information; under such circumstances, expert experience can be incorporated in the evaluation process to a limited degree. The technique described in this paper has a high potential to aid decisions when many opinions and options must be considered simultaneously. PMID:16364535
Cram, Silke; Sommer, Irene; Morales, Luis-Miguel; Oropeza, Oralia; Carmona, Estela; González-Medrano, Francisco
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.
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.
Full Text Available SciELO Brazil | Language: English Abstract in english The objective of this study was to evaluate the effects of storage time and temperature on the characteristics of vegetable-type soybean grain (cultivar BRS 267) minimally processed and to define the best conditions for its storage. The evaluation was performed by measurement of vitamin C levels, we [...] ight loss and color parameters (L*, a*, and b*). The time of storage of vegetable-type soybean grains minimally processed and storage in Styrofoam trays and wrapped with PVC film, caused a decreased in vitamin C levels and color parameters and increased weight loss. This process was intensified with higher temperature at 25 °C than 5°C. To maintain appropriate levels of vitamin C, weight and color of vegetable-type soybean grains minimally processed and storage in trays wrapped in plastic wrap, recommended storage for 3 days at 5°C.
Karina, Czaikoski; Mercedes Concórdia, Carrão-Panizzi; Josemeyre Bonifácio da, Silva; Elza Iouko, Ida.
Praha : CERGE-EI, 2001 - (Hanousek, J.; Lízal, L.), s. 107-115 ISBN 80-86286-69-X R&D Projects: GA AV ?R KSK9058117 Institutional research plan: CEZ:AV0Z7085904 Keywords : Czech Republic * ecology Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/books/pdf_01/VI.pdf
Lízal, Lubomír; Tošovská, Eva
We find that active P uptake is an essential mechanism for sustaining P availability on long timescales, whereas biotic de-occlusion might serve as a buffer on timescales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modelling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth, and that vegetation on old soils has a smaller biomass production rate when P becomes limiting. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and ecological timescales under different environmental settings.
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.
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.
Background:: There is a possibility for the presence of Helicobacter pylori in vegetables due to their close contact with polluted water, soil and feces. Objectives:: This study was carried out to detect the presence of H. pylori in vegetables and salads in Iran. Materials and Methods:: In total, 460 vegetable and salad samples were collected and transferred immediately to the laboratory. All samples were cultured and tested for the presence of H. pylori using the Polymerase Chain Rea...
Shahrzad Atapoor; Farhad Safarpoor Dehkordi; Ebrahim Rahimi
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
The abiotic conditions of the immediate environment of organisms are key factors for a better understanding of ecological and evolutionary processes. Yet, information in this regard is biased towards some habitat types, landscapes, and organisms. Here, we present a 2-year comparative study of the microclimatic properties (temperature, relative humidity, and their fluctuation) of three cavity types (nest boxes, cavities in bridges, and burrows in sandy cliffs) in an arid environment. We found marked and consistent months-long differences in microclimate among the three cavity types. Nest boxes were colder than the other cavity types, with temperature oscillations being an order of magnitude higher than in other cavity types. In contrast, microclimate was very stable in burrows and cavities in bridges, the former being generally warmer and drier than the latter. We also discuss the biological implications of microclimatic conditions and its variation in different cavity types by presenting two case studies, namely the temperature-humidity index and water vapor pressure during the hatching period of an endotherm and the chilling period during the diapause of an ectotherm ectoparasite. We stress the need for comparative studies of the same organisms subjected to different microclimates given the important ecological, evolutionary, and conservation implications. PMID:24573376
Amat-Valero, M; Calero-Torralbo, M A; Václav, R; Valera, F
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 computhed 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.
This thesis evaluates the effect of vegetation type and increased snow depth on soil temperature and annual CO2 efflux in an arctic tundra region. Snow fences were set up to manipulate snow accumulation in heath and meadow vegetation on Spitsbergen. Field campaigns lasted from July 2007 - July 2008. CO2 efflux, measured by means of a dark and closed-dynamic soil flux chamber, showed seasonal variation and was lowest in winter time. Soil temperature had a strong influence on efflux year-round,...
Drought is a complex natural hazard with severe impacts on ecosystems. Several studies have highlighted links between drought spatio-temporal patterns and wildfire behaviour. Recent research showed drought can affect the development of catastrophic fires through influence on the spatial connectivity of dry fuel patches. Wildfires that are initiated at isolated ignition points (‘within patch scale’) can propagate non-linearly across landscapes (“among-patches”) if fuels are sufficiently dry and connected. Consequently, accurate mapping of drought at fine spatial resolution represents a priority to monitor “among-patches” continuity of flammable fuels in fire prone regions. Traditional methods of drought monitoring are based on meteorological indices (MI) calculated from weather stations data. The network of weather stations is often sparse and inadequate to produce fine spatial resolution surfaces of MI especially across remote forested areas. Spectral indices (SI) based on satellite data provide sound and cost-effective alternatives to MI, offering spatially dense information regularly recorded over large areas across a wide range of wavelengths. Since a considerable number of SI have been proposed as drought monitoring tool, the selection of the most appropriate index for a specific region represents an essential operation to ensure efficiency in drought mapping. In this study we propose a comprehensive analysis to evaluate the performance of a wide range of Vis, NIR and SWIR based SI towards drought condition monitoring over fire prone vegetation types, using the Sydney Basin bioregion (Australia) as case study. All spectral indices were derived from reflectance data sets obtained from MODIS Terra time series (2000-2009). The relationships between SI and drought conditions were analysed using a meteorological index (Standardized Precipitation Index, SPI) as rainfall deficiency indicator. The spatial and temporal co-variability between SPI and spectral indices was analysed and the sensitivity of MODIS indices to drought-related vegetation conditions was tested against a series of dry/wet years. Strong relationships between MODIS data and drought conditions were found. All spectral indices showed strong temporal and spatial correlations with SPI, with higher sensitivity to drought among SWIR based indices. The results revealed also that the spectral index routinely used by bushfire authorities in the Sydney Basin for drought monitoring is not the best indicator available, and there are potentials for the development of an enhanced MODIS-based monitoring tool. Our findings confirmed that extensive comparative analysis is necessary prior to implementation of SI in drought monitoring systems.
Caccamo, G.; Chisholm, L. A.; Bradstock, R.; Puotinen, M. L.
Current remote sensing based models of vegetation-atmosphere carbon exchange are complex and require a large number of input parameters not all of which can be determined directly from remote sensing. Models based entirely on remote sensing data would simplify the estimation of vegetation carbon fluxes and potentially reduce errors associated with estimation of ground based parameters. We examined the relationship between the enhanced vegetation index (EVI) from the MODIS satellite sensor and gross carbon flux measurements from 10 eddy covariance towers in a wide range of vegetation types across the United States (US). There was a strong general relationship (r2 = 0.60) between EVI and gross flux when all the data were considered together. In fact, this correlation was as good as that between the MODIS GPP product and measured gross flux (r2 = 0.54), suggesting that EVI could be used as a simple alternative to more complex models. However, the strength of the relationship between EVI and gross flux varied widely when data for individual sites were considered alone. Although there was a tendency for sites with deciduous vegetation to have better correlations than those with evergreen vegetation, some of the evergreen forest sites also had reasonably strong correlations. Sites in the western US had weaker correlations between EVI and gross flux than those in the eastern US. The strength of the correlation between EVI and gross flux was a function of the amount of summer rainfall and the minimum winter temperature at each site. This may be a result of climatic effects on the amount of understory vegetation (which tends to be deciduous even when the overstory is evergreen) and the phenology of changes in vegetation greenness relative to carbon flux. We explored the mechanistic explanations for these relationships across vegetation types, geographic locations and climatic variability. Better understanding of those factors that lead to good correlations between EVI and gross flux would allow us to use this relationship with confidence for at least a portion of the country and may lead to development of other simple models for carbon flux in areas where the EVI/gross flux relationship is weak.
Sims, D. A.; Rahman, A. F.; Cordova, V. D.; El-Masri, B. Z.
Full Text Available Background:: There is a possibility for the presence of Helicobacter pylori in vegetables due to their close contact with polluted water, soil and feces. Objectives:: This study was carried out to detect the presence of H. pylori in vegetables and salads in Iran. Materials and Methods:: In total, 460 vegetable and salad samples were collected and transferred immediately to the laboratory. All samples were cultured and tested for the presence of H. pylori using the Polymerase Chain Reaction technique. Results:: The results showed that 44 of 460 samples (9.56% were positive for H. pylori using the culture method. The Polymerase Chain Reaction technique showed that 50 of 460 samples (10.86% were positive for H. pylori. Un-washed leek, traditional salad, un-washed basil and un-washed lettuce were the most commonly contaminated samples. The presence of the bacteria in various vegetables was statistically significant (P < 0.05. Conclusions:: Vegetables are a new source of H. pylori and accurate washing of vegetables improves such contaminations. Keywords: Helicobacter pylori; Vegetables; Culture; Polymerase Chain Reaction
Estado ecológico de ríos y vegetación ribereña en el contexto de la nueva Ley General de Aguas de México / Ecological status of rivers and riparian vegetation within the new General Mexican Water's Law context
Full Text Available Los ríos son unidades vitales en el funcionamiento de las cuencas que, debido al transporte y a la circulación cíclica del agua, permiten la existencia de los seres vivos. Poseen gran valor ecológico y ambiental dada su influencia sobre otros ecosistemas y los beneficios que proporcionan al hombre, [...] tanto para consumo como para riego y uso en los ámbitos agrícola e industrial. Sin embargo, casi todos los ríos de México presentan algún tipo de deterioro. Alrededor de 73 % de los sistemas acuáticos muestran contaminación, lo que empobrece la salud de estos ecosistemas. El objetivo de este trabajo es proponer que en la formulación de la nueva ley general de aguas se considere la regulación de la vegetación ribereña, pues su influencia en el mantenimiento y en la rehabilitación del estado ecológico de los ríos es fundamental. Se sugiere que la nueva ley contenga una sección de protección ambiental en la que se incluya a la vegetación ribereña como elemento clave para proteger, conservar y restaurar los ríos. Asimismo, que la delimitación de dicha vegetación se apegue a las condiciones naturales de inundación del cauce, con una frecuencia de una vez cada ocho años, de acuerdo con la variabilidad del flujo. Además, su manejo debe tomar en cuenta la reforestación y el mantenimiento de especies vegetales nativas de cada región. Abstract in english Rives are vital units in the functioning of the watersheds that, due to the transportation and circulation of water, allow the existence of life. They are of great ecological and environmental value because of their influence on other ecosystems as well as the benefits they give to humankind, not on [...] ly in the consumption for irrigation but also in the use in the agricultural and industrial areas. However, almost all the rivers in Mexico show a certain type of deterioration. About 70 % of the aquatic systems shows contamination which diminishes the health of these ecosystems. The objective of this work is to propose that the riparian vegetation should be included in the making of the new general law of water because its influence on the maintenance and rehabilitation of the ecological state of rivers is fundamental. It has been suggested a new law that contains a section of environmental protection which includes the riparian vegetation as a key element to protect, preserve, and restore rivers. Likewise, the boundaries of this vegetation should be according to the natural conditions of flooding in the bed of the river, with a once-in-every eight years- frequency, according to the variability of flow. In addition, its handling must consider the reforestation and maintenance of native vegetation species in each region.
Mayra, MENDOZA CARIÑO; Abel, QUEVEDO NOLASCO; Ángel, BRAVO VINAJA; Héctor, FLORES MAGDALENO; María de Lourdes, DE LA ISLA DE BAUER; Francisco, GAVI REYES; Bertha Patricia, ZAMORA MORALES.
Nature-based tourism in protected areas has increased and diversified dramatically during the last decades. Different recreational activities have a range of impacts on natural environments. This paper reports results from a comparison of the impacts of hiking, cross-country skiing and horse riding on trail characteristics and vegetation in northern Finland. Widths and depths of existing trails, and vegetation on trails and in the neighbouring forests were monitored in two research sites during 2001 and 2002. Trail characteristics and vegetation were clearly related to the recreational activity, research site and forest type. Horse trails were as deep as hiking trails, even though the annual number of users was 150-fold higher on the hiking trails. Simultaneously, cross-country skiing had the least effect on trails due to the protective snow cover during winter. Hiking trail plots had little or no vegetation cover, horse riding trail plots had lower vegetation cover than forest plots, while skiing had no impact on total vegetation cover. On the other hand, on horse riding trails there were more forbs and grasses, many of which did not grow naturally in the forest. These species that were limited to riding trails may change the structure of adjacent plant communities in the long run. Therefore, the type of activities undertaken and the sensitivity of habitats to these activities should be a major consideration in the planning and management of nature-based tourism. Establishment of artificial structures, such as stairs, duckboards and trail cover, or complete closure of the site, may be the only way to protect the most sensitive or deteriorated sites. PMID:18930578
Törn, A; Tolvanen, A; Norokorpi, Y; Tervo, R; Siikamäki, P
Ecological theory differentiates rainforest and open vegetation in many regions as functionally divergent alternative stable states with transitional (ecotonal) vegetation between the two forming transient unstable states. This transitional vegetation is of considerable significance, not only as a test case for theories of vegetation dynamics, but also because this type of vegetation is of major economic importance, and is home to a suite of species of conservation significance, including the...
Tng, David Y. P.; Jordan, Greg J.; Bowman, David M. J. S.
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
Characterization of spatial and temporal variation of soil respiration coupled with fine root and rhizomorph dynamics is necessary to understand the mechanisms that regulate soil respiration. A dense wireless network array of soil CO2 sensors in combination with minirhizotron tubes was used to continuously measure soil respiration over 1 yr in a mixed conifer forest in California, USA, in two adjacent areas with different vegetation types: an area with woody vegetation (Wv) and an area with scattered herbaceous vegetation (Hv). Annual soil respiration rates and the lengths of fine roots and rhizomorphs were greater at Wv than at Hv. Soil respiration was positively correlated with fine roots and rhizomorphs at Wv but only with fine roots at Hv. Diel and seasonal soil respiration patterns were decoupled with soil temperature at Wv but not at Hv. When decoupled, higher soil respiration rates were observed at increasing temperatures, demonstrating a hysteresis effect. The diel hysteresis at Wv was explained by including the temperature-dependent component of soil respiration and the variation dependent on photosynthetically active radiation. The results show that vegetation type and fine root and rhizomorph dynamics influence soil respiration in addition to changes in light, temperature and moisture. PMID:19086292
Vargas, Rodrigo; Allen, Michael F
In May 2000, the Cerro Grande Fire burned approximately 17,200 ha in north-central New Mexico as the result of an escaped prescribed burn initiated by Bandelier National Monument. The interaction of large-scale fires, vegetation, and elk is an important management issue, but few studies have addressed the ecological implications of vegetative succession and landscape heterogeneity on ungulate populations following large-scale disturbance events. Primary objectives of this research were to identify elk movement pathways on local and landscape scales, to determine environmental factors that influence elk movement, and to evaluate movement and distribution patterns in relation to spatial and temporal aspects of the Cerro Grande Fire. Data collection and assimilation reflect the collaborative efforts of National Park Service, U.S. Forest Service, and Department of Energy (Los Alamos National Laboratory) personnel. Geographic positioning system (GPS) collars were used to track 54 elk over a period of 3+ years and locational data were incorporated into a multi-layered geographic information system (GIS) for analysis. Preliminary tests of GPS collar accuracy indicated a strong effect of 2D fixes on position acquisition rates (PARs) depending on time of day and season of year. Slope, aspect, elevation, and land cover type affected dilution of precision (DOP) values for both 2D and 3D fixes, although significant relationships varied from positive to negative making it difficult to delineate the mechanism behind significant responses. Two-dimensional fixes accounted for 34% of all successfully acquired locations and may affect results in which those data were used. Overall position acquisition rate was 93.3% and mean DOP values were consistently in the range of 4.0 to 6.0 leading to the conclusion collar accuracy was acceptable for modeling purposes. SAVANNA, a spatially explicit, process-oriented ecosystem model, was used to simulate successional dynamics. Inputs to the SAVANNA included a land cover map, long-term weather data, soil maps, and a digital elevation model. Parameterization and calibration were conducted using field plots. Model predictions of herbaceous biomass production and weather were consistent with available data and spatial interpolations of snow were considered reasonable for this study. Dynamic outputs generated by SAVANNA were integrated with static variables, movement rules, and parameters developed for the individual-based model through the application of a habitat suitability index. Model validation indicated reasonable model fit when compared to an independent test set. The finished model was applied to 2 realistic management scenarios for the Jemez Mountains and management implications were discussed. Ongoing validation of the individual-based model presented in this dissertation provides an adaptive management tool that integrates interdisciplinary experience and scientific information, which allows users to make predictions about the impact of alternative management policies.
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.
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.
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 SCWigital number (DN) increase observed in the digital SEASAT data. The brightest areas in the Chickahominy, Virginia, drainage, containing P. virginica about 0.4 m high, contrast with the brightest areas in the Blackwater, Maryland, marshes, which contain mature loblolly pine in standing water. The darkest vegetated area in the Chickahominy drainage contains a forest of Nyssa aquatica (water tupelo) about 18 m high, while the darkest vegetated area in the Blackwater marshes contains the marsh plant Spartina alterniflora, 0.3 m high. 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.
Krohn, M. Dennis; Milton, N. M.; Segal, Donald B.
The impact of geology, climate, soil type and vegetation on forest humus forms was studied in the Veneto Region (northern Italy). A total of 352 study sites were compared by Redundancy Analysis (RDA). Humus forms were described by the structure (micro-, meso-, or macro-aggregated) of the organo-mineral A horizon, by the thickness of litter horizons and by their nomenclature, which followed the morpho-functional classification recently proposed for inclusion in the WRB-FAO. The size of aggrega...
Ponge, Jean-franc?ois; Sartori, Giacomo; Garlato, Adriano; Ungaro, Fabrizio; Zanella, Augusto; Jabiol, Bernard; Obber, Silvia
Aeolian processes redistribute sediments and nutrients within arid landscapes with important implications on the composition and structure of vegetation. Aeolian processes, on the other hand, are affected by vegetation cover and disturbances. For example, it has been reported that wind erosion is enhanced by fire occurrences, though it is still unclear how this post-fire erosion activity is affected by the vegetation type. In this study we monitored wind erosion activity in a managed grassland (CRP) and in a shrub encroached grassland within the Cimarron National Grasslands (KS). Measurements started after a naturally occurring wildfire and included both field observations - BSNE dust samplers, SENSIT particle impact sensors - and laboratory wind tunnel experiments. The results indicate that, by decreasing the threshold shear velocity (due to vegetation removal and soil water repellency), fires enhance the soil erodibility both in the CRP grassland and in the shrub-encroached grassland. The initial post-fire horizontal dust fluxes in grasslands and adjacent shrub encroached grasslands were comparable. However, the post fire recovery (decline in erosion activity) was rapid in the case of grasslands, while erosion activity remained high in the shrub encroached grasslands for several months after the wild fire. Our results support the hypothesis that woody plant encroachment decreases the resilience of semi arid grasslands - the capacity of these systems to recover from disturbances. This higher post-fire loss and redistribution of soil resources from shrub encroached grasslands further inhibits grass recovery, thereby favoring the shrub encroachment process.
Ravi, S.; Zobeck, T. M.; D'Odorico, P.; Baddock, M.
The causes of a greening trend detected in the Arctic using the normalized difference vegetation index (NDVI) are still poorly understood. Changes in NDVI are a result of multiple ecological and social factors that affect tundra net primary productivity. Here we use a 25 year time series of AVHRR-derived NDVI data (AVHRR: advanced very high resolution radiometer), climate analysis, a global geographic information database and ground-based studies to examine the spatial and temporal patterns of vegetation greenness on the Yamal Peninsula, Russia. We assess the effects of climate change, gas-field development, reindeer grazing and permafrost degradation. In contrast to the case for Arctic North America, there has not been a significant trend in summer temperature or NDVI, and much of the pattern of NDVI in this region is due to disturbances. There has been a 37% change in early-summer coastal sea-ice concentration, a 4% increase in summer land temperatures and a 7% change in the average time-integrated NDVI over the length of the satellite observations. Gas-field infrastructure is not currently extensive enough to affect regional NDVI patterns. The effect of reindeer is difficult to quantitatively assess because of the lack of control areas where reindeer are excluded. Many of the greenest landscapes on the Yamal are associated with landslides and drainage networks that have resulted from ongoing rapid permafrost degradation. A warming climate and enhanced winter snow awarming climate and enhanced winter snow are likely to exacerbate positive feedbacks between climate and permafrost thawing. We present a diagram that summarizes the social and ecological factors that influence Arctic NDVI. The NDVI should be viewed as a powerful monitoring tool that integrates the cumulative effect of a multitude of factors affecting Arctic land-cover change.
Ro?. 9, ?. 4 (2001), s. 351-358. ISSN 1061-2971 R&D Projects: GA MŠk ME 076 Institutional research plan: CEZ:AV0Z6066911 Keywords : soil microfungi * frequency of species occurrence * post-mining dumps Subject RIV: EH - Ecology, Behaviour Impact factor: 1.011, year: 2001
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
Ro?. 14, ?. 1 (2011), 132-147. ISSN 1402-2001 R&D Projects: GA AV ?R IAA600050802 Institutional research plan: CEZ:AV0Z60050516 Keywords : alpine vegetation * Classification * Trans-Himalaya Subject RIV: EF - Botanics Impact factor: 1.678, year: 2011
Dvorský, Miroslav; Doležal, Ji?í; de Bello, Francesco; Klimešová, Jitka; Klimeš, Leoš
Modeling and monitoring plankton functional types (PFTs) is challenged by the insufficient amount of field measurements of ground truths in both plankton models and bio-optical algorithms. In this study, we combine remote sensing data and a dynamic plankton model to simulate an ecologically sound spatial and temporal distribution of phyto-PFTs. We apply an innovative ecological indicator approach to modeling PFTs and focus on resolving the question of diatom–coccolithophore coexistence ...
Palacz, A. P.; St John, M. A.; Brewin, R. J. W.; Hirata, T.; Gregg, W. W.
The National Ecological Observatory Network (NEON), being funded by the National Science Foundation, is a continental-scale research platform for discovering, understanding and forecasting the impacts of climate change, land-use change, and invasive species on ecology. Local site-based flux tower and field measurements will be coordinated with high resolution, regional airborne remote sensing observations. The NEON Airborne Observation Platform (AOP) consists of an aircraft platform carrying remote sensing instrumentation designed to achieve sub-meter to meter scale ground resolution to bridge scales from organism and stand scales to the scale of satellite based remote sensing. Data from the AOP will be openly available to the science community and will provide quantitative information on land use change, and changes in ecological structure and chemistry including the presence and effects of invasive species. Remote sensing instrumentation consists of an imaging spectrometer measuring surface reflectance over the continuous wavelength range from 400 to 2500 nm with 10 nm resolution, a scanning, small footprint waveform LiDAR for 3-D canopy structure measurements and a high resolution airborne digital camera. The AOP science objectives, key mission requirements, the conceptual design and development status are presented.
Johnson, Brian R.; Kampe, Thomas U.; Kuester, Michele A.; Keller, Michael
Re-vegetation is mainly applied into regeneration in opencast mine to improve the soil quality. It is very important to choose feasible vegetation types for soil restoration. In this study, three typical forest restoration types were studied at Antaibao mine, namely, Medicago sativa, mixed forests Pinus taebelaefolius-Robinia pseudoacacia-Caragana korshinskii and Elaeagnus angustifolia-Robinia pseudoacacia-Caragana korshinskii-Hipophae rhamnoides, to determine the nutrient contents and enzyme activities in different soil layers. The results showed that re-vegetation markedly increased soil nutrient contents and the enzyme activities during the restoration process. The nutrient content of soil in the P. taebelaefolius-R. pseudoacacia-C. korshinskii mixed forest field was significantly higher than those in other plots. It was found that the soil of the P. taebelaefolius-R. pseudoacacia-C. korshinskii mixed forest had the highest integrated fertility index values. In conclusion, the restoration effects of the P. zaebelaefolius-R. pseudoacacia-C. Korshinskii mixed forest was better than that of E. angustifolia-R. pseudoacacia-C. korshinskii-H. rhamnoides, while M. sativa grassland had the least effect. PMID:24289011
Wang, Xiang; Li, Jin-chuan; Yue, Jian-ying; Zhou, Xiao-mei; Guo, Chun-yan; Lu, Ning; Wang, Yu-hong; Yang, Sheng-quan
Sclerophyllus scrub formations, the main vegetation type in many islands of the Aegean area, are characterized by their high biodiversity. Dominant shrub species of sclerophyllus formations are well adapted to dry season conditions by various anatomical and physiological mechanisms. As a result, their biomass acts as very flammable fine fuel, and consequently wild fires are very common in these ecosystems. Wildfire effects on vegetation and biodiversity in the Mediterranean basin have been studied and the results are diverse depending mainly on vegetation type and frequency of fire. The aim of this study was to evaluate the effects of wildfire on floristic diversity and species composition in three thermo-Mediterranean vegetation types 1) Sacropoterium spinosum phrygana, 2) low formations of Cistus creticus and 3) low formations of Cistus creticus in abandoned terraces. The research was conducted in Enoussa islet, which is located northeastern of Chios Island, in May 2013 (one year after the fire). Vegetation sampling was performed along five transects placed in recently burned and in adjacent unburned sites of each vegetation type. The plant cover and the floristic composition were measured, while diversity, evenness and dominance indices were determined for the vegetation data. Vegetation cover and the floristic diversity were significant lower and higher respectively in burned areas in comparison to the unburned. The woody species followed by the annual grasses and the annual forbs dominated in both burned and unburned areas. However, the woody species were significantly decreased in the burned areas in all vegetation types, while the annual grasses only in the burned areas of Sacropoterium spinosum phrygana and Cistus creticus in abandoned terraces. Inversely, the annual forbs significantly increased in the burned sites of Cistus creticus formations. The highest value of Morisita-Horn Index of similarity between burned and unburned sites (beta diversity) was observed for the Sacropoterium spinosum phrygana (0.83) indicating limited effect of fire on the species composition of this vegetation type.
Abraham, Eleni; Kyriazopoulos, Apostolos; Korakis, George; Parissi, Zoi; Chouvardas, Dimitrios
Attempts were made to study the gene introgression for high physiological quality from adapted cultivars in the vegetable soybean (exotic). Promising results were obtained for all topocrosses, with increased in germination percentage in majority. General mean of the germination percentage in topcrosses with large seeds exotic parental showed an increase from 28 to 46%, and topcrosses with small seeds exotic parental, from 54 up to 60%, both cases compared to self pollinated exotic parental. R...
Yokomizo, Gilberto K.; Vello, Natal A.
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.
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.
Evidence has accumulated indicating that oxidative stress may play a key role in the etiology of diabetic complications and the protective effects of antioxidant nutrients are a topic of intense research. The purpose of this study was both to obtain preliminary data on the effect of a diet high in fruit and vegetables on metabolic control and the oxidative status of patients with type 2 onset diabetes, and to identify the most useful biochemical parameters for future research. At the beginning of the study all subjects were asked to follow their usual diet and keep a seven-day food diary. Diabetic patients then received a dietary treatment designed to ensure a daily intake of 700-1000 g of fruit and vegetables; no dietary advice was given to controls. Dietary antioxidants, redox status markers, and parameters of metabolic control were measured in plasma and erythrocytes before and after the diet. Before following the diet, diabetic patients had lower levels of ascorbic acid, beta-carotene, and alpha-tocopherol/cholesterol ratio than controls. After the diet these parameters increased and there was also a reduction in total antioxidant capacity, uric acid, and malondialdehyde and a rise in reduced glutathione accompanied by a reduction in body mass index and cholesterol. In conclusion, a high consumption of fruit and vegetables by diabetic patients not receiving pharmacological treatment, seems to produce an improvement in some redox status parameters. PMID:15628668
Giammarioli, Stefania; Filesi, Carmelina; Vitale, Barbara; Cantagallo, Anna; Dragoni, Francesco; Sanzini, Elisabetta
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
Zonal patterns of salt marsh plants and physical conditions have been addressed primarily across the elevation gradient from inland to coastline rather than across tidal creeks in relation to their hydro-geomorphic processes such as bar formation and bank erosion. We found at a Danish marsh that by shaping major geomorphic features and providing sediments to the adjacent sites, fluvial-geomorphic processes of tidal creeks exert fundamental controls on the cross-channel distribution of abiotic and biotic factors. These results point to a need for biogeomorphic and landscape ecological perspectives to fully understand the underlying structure and geographic variability in salt marshes.
Kim, Daehyun; Cairns, David M.
Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Foram conduzidos três experimentos com o objetivo de determinar a composição química e os valores de energia metabolizável da glicerina vegetal semipurificada e verificar o desempenho e as características de carcaça de codornas de corte alimentadas com rações contendo níveis crescentes de glicerina. [...] No experimento 1, foram utilizadas 50 codornas, alojadas em gaiolas de metabolismo. Os tratamentos consistiram de uma ração referência e de uma ração teste contendo nível de substituição de 10% de glicerina, com cinco repetições de cinco codornas por repetição. O valor de energia metabolizável aparente corrigida para balanço de nitrogênio da glicerina foi de 3.069kcal/kg. No experimento 2, foram utilizadas 640 codornas, distribuídas em um delineamento inteiramente ao acaso, com cinco tratamentos (ração controle e níveis de glicerina = 4, 8, 12 e 16%) e quatro repetições com 32 aves em cada repetição. Não foram observadas diferenças (P>0,05) para consumo de ração e ganho de peso. A inclusão de glicerina, na fase de um a 14 dias de idade, piorou a conversão alimentar. No experimento 3, foram utilizadas 440 codornas, distribuídas em um delineamento inteiramente ao acaso, com cinco tratamentos e quatro repetições com 22 aves em cada repetição. Os tratamentos utilizados foram os mesmos do experimento 2. O consumo de ração aumentou linearmente (P Abstract in english Three experiments were carried out to determine the chemical composition and metabolizable energy values of vegetable semi-purified glycerin and verify the performance and carcass yeild of meat type quai, fed with diets containing increasing levels of glycerin. In the first experiment 50 quails were [...] used, housed in metabolism cages. The treatments consisted of a reference diet and a test diet containing the replacement level of 10% glycerin, with five replications of five quails per replication. The value of apparent metabolisable energy corrected by nitrogen balance of glycerin was 3.069 kcal/kg. In the second experiment 640 quails were used, distributed in a completely randomized design, with five treatments (control diet and four levels = 4, 8, 12 and 16% of glycerin), four replications with 32 birds per replication. There were no differences (P>0.05) on feed intake and weight gain. The inclusion of glycerin (1 - 14 days of age) decrease feed:gain ratio. In the third experiment, 440 quails were used, distributed in a completely randomized design, with five treatments, with four replications with 22 birds per repetition. The treatments used were the same as the second trial. The feed intake increased linearly (P
E., Batista; A.C., Furlan; A.P.S., Ton; T.J., Pasquetti; T.C.O., Quadros; D.O., Grieser; V., Zancanela.
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.
Vegetation dynamics and performance are strongly influenced by environmental conditions. Specifically, light, precipitation, and air temperature exert a predominant role. These climatic variables covariate with elevation and aspect in areas of complex terrain. Quantification of specific elevation and aspect effects on vegetation productivity and mass and energy fluxes can lead to a better understating of environment-driven distribution of vegetation and parsimonious up-scaling parameterizations useful in hydrological applications. A detailed characterization of climatic differences with elevation is however a daunting task. In this study, two synthetic climate gradients, constructed using hourly meteorological data and a stochastic weather generator, AWE-GEN, are used to force a mechanistic ecohydrological model, Tethys-Chloris, and quantify energy, carbon, and water fluxes for three generic Plant Functional Types (PFTs). One gradient is representative of a dry, sheltered alpine valley (Valais), whereas the other one characterizes a wet, exposed mountain side (Bernese Oberland). Thirty year long time series of cross-correlated precipitation, air temperature, relative humidity, wind speed, solar radiation, and atmospheric pressure for elevation bands from 500 up to 3500 m a.s.l. are generated to represent the climatic differences. The incoming radiation is successively recalculated for different combinations of aspect and slope. Under these specific climatic forcing conditions, the response of deciduous and evergreen trees, and grass typical of the Alpine system is investigated. The parameterization of the ecohydrological model was tested to reproduce vegetation productivity and energy fluxes for several locations in an Alpine climate or similar conditions (Fluxnet dataset) and to correctly simulate snowpack dynamics for forested and open sites worldwide (Snowmip-2 dataset). The three PFTs evolve at different elevations and aspects for dry and wet conditions. Results indicate that differences in hydrological fluxes across PFTs are more evident for the dry, water-limited scenario, rather than for the wet scenario. The optimum for vegetation productivity shifts from low elevations of 500-1000 m in wet conditions to higher elevations (of about 1800-2200 m) for the dry altitudinal gradient. By intercepting snow and shading ground surface, PFTs affect differently snow cover distribution and seasonal duration. The overall role of elevation was found to be predominant when compared to the role of aspect, regardless of the climate type. Nonetheless, we speculate that this is not always the case and the role of aspect, or contributing area might become the dominant control for different ecosystems.
Fatichi, S.; Ivanov, V. Y.; Rimkus, S.; Caporali, E.; Burlando, P.
The impacts of global climate change are expected to be most severe at high northern latitudes. There is now strong evidence to support the hypothesis that such changes have had dramatic effects on the phenology of spring vegetative growth in these areas. One aspect of this change that has not been thoroughly investigated is how these changes vary across habitats and whether sub-Arctic and Arctic avifauna have adapted to shifts in plant phenology by modifying the timing of migration and nesting. A recent study showed that certain bird species have experienced population decline due to the varied timing of seasonal events and points to the fact that the degree of risk facing migratory birds is not well quantified. Plant phenology is especially sensitive to annual variation in temperature and precipitation and is a major determinant of plant species distribution, making it a good indicator of climate change effects. Migratory birds are considered one of the most vulnerable groups to the impacts of climate change because climate affects bird movement and distribution through species-specific physiological tolerances and changes in food and habitat resources. In this study we analyze the evidence for long-term plant phenology changes across different biomes of Alaska using satellite remote sensing techniques. We correlate this variability with ground-based measurements of avian migration and breeding. Specifically, we try to determine if the timing of spring green-up is synchronized across breeding areas or whether the process has become fractured across intervening biomes, potentially disrupting the timing of migration and breeding, putting species at risk. Using satellite-based time series of Normalized Difference Vegetation Index (NDVI) data, we create spatially explicit maps of seasonal vegetation metrics and correlate those with the timing and distribution of avian migrant populations. Preliminary investigation focused on the last 10 year period (2000-2009) and utilized Moderate Resolution Imaging Spectroradiometer (MODIS) data at a 250m spatial resolution to characterize variability in the start of season and magnitude of NDVI at different times throughout the migration period. NDVI seasonality measurements are compared with avian chronology metrics (i.e., first arrival date, peak nest initiation, etc.) for each species at each site. Results are evaluated and spatially explicit trends are identified, including temporal shifts in start of season, variability in seasonal production, and altered migratory activities. The findings of this study, coupled with other historical analysis of this relationship, will aid in predicting future impacts of climate-induced habitat change on avian migration patterns.
Budde, M. E.; Ward, D. H.; Ely, C. R.; Handel, C. M.; Hupp, J. W.
In-situ burning of oiled wetlands potentially provides a cleanup technique that is generally consistent with present wetland management procedures. The effects of water depth (+10, +2, and -2 cm), oil type (crude and diesel), and oil penetration of sediment before the burn on the relationship between vegetation recovery and soil temperature for three coastal marsh types were investigated. The water depth over the soil surface during in-situ burning was a key factor controlling marsh plant recovery. Both the 10- and 2-cm water depths were sufficient to protect marsh vegetation from burning impacts, with surface soil temperatures of Sagittaria lancifolia but did not detrimentally affect the recovery of Spartina patens and Distichlis spicata. Oil type (crude vs diesel) and oil applied to the marsh soil surface (0.5 L x m(-2)) before the burn did not significantly affect plant recovery. Thus, recovery is species-specific when no surface water exists. Even water at the soil surface will most likely protect wetland plants from burning impact. PMID:15819246
Lin, Qianxin; Mendelssohn, Irving A; Bryner, Nelson P; Walton, William D
In old and heavily weathered soils, the availability of P might be so small that the primary production of plants is limited. However, plants have evolved several mechanisms to actively take up P from the soil or mine it to overcome this limitation. These mechanisms involve the active uptake of P mediated by mycorrhiza, biotic de-occlusion through root clusters, and the biotic enhancement of weathering through root exudation. The objective of this paper is to investigate how and where these processes contribute to alleviate P limitation on primary productivity. To do so, we propose a process-based model accounting for the major processes of the carbon, water, and P cycles including chemical weathering at the global scale. Implementing P limitation on biomass synthesis allows the assessment of the efficiencies of biomass production across different ecosystems. We use simulation experiments to assess the relative importance of the different uptake mechanisms to alleviate P limitation on biomass production. We find that active P uptake is an essential mechanism for sustaining P availability on long timescales, whereas biotic de-occlusion might serve as a buffer on timescales shorter than 10 000 yr. Although active P uptake is essential for reducing P losses by leaching, humid lowland soils reach P limitation after around 100 000 yr of soil evolution. Given the generalized modelling framework, our model results compare reasonably with observed or independently estimated patterns and ranges of P concentrations in soils and vegetation. Furthermore, our simulations suggest that P limitation might be an important driver of biomass production efficiency (the fraction of the gross primary productivity used for biomass growth), and that vegetation on old soils has a smaller biomass production rate when P becomes limiting. With this study, we provide a theoretical basis for investigating the responses of terrestrial ecosystems to P availability linking geological and ecological timescales under different environmental settings.
Buendía, C.; Arens, S.; Hickler, T.; Higgins, S. I.; Porada, P.; Kleidon, A.
Modeling and monitoring plankton functional types (PFTs) is challenged by the insufficient amount of field measurements of ground truths in both plankton models and bio-optical algorithms. In this study, we combine remote sensing data and a dynamic plankton model to simulate an ecologically sound spatial and temporal distribution of phyto-PFTs. We apply an innovative ecological indicator approach to modeling PFTs and focus on resolving the question of diatom-coccolithophore coexistence in the subpolar high-nitrate and low-chlorophyll regions. We choose an artificial neural network as our modeling framework because it has the potential to interpret complex nonlinear interactions governing complex adaptive systems, of which marine ecosystems are a prime example. Using ecological indicators that fulfill the criteria of measurability, sensitivity and specificity, we demonstrate that our diagnostic model correctly interprets some basic ecological rules similar to ones emerging from dynamic models. Our time series highlight a dynamic phyto-PFT community composition in all high-latitude areas and indicate seasonal coexistence of diatoms and coccolithophores. This observation, though consistent with in situ and remote sensing measurements, has so far not been captured by state-of-the-art dynamic models, which struggle to resolve this "paradox of the plankton". We conclude that an ecological indicator approach is useful for ecological modeling of phytoplankton and potentially higher trophic levels. Finally, we speculate that it could serve as a powerful tool in advancing ecosystem-based management of marine resources.
Palacz, A. P.; St. John, M. A.; Brewin, R. J. W.; Hirata, T.; Gregg, W. W.
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
Ecological site descriptions (ESDs) are a useful technology for conveying the ecological potential of specific land types and the possible responses of vegetation and soils on them to management. Yet some of the same traits that lend ESDs their management utility (e.g., narrative format and site-spe...
We present quantitative reconstructions of regional vegetation cover in north-western Europe, western Europe north of the Alps, and eastern Europe for five time windows in the Holocene [around 6k, 3k, 0.5k, 0.2k, and 0.05k calendar years before present (bp)] at a 1° × 1° spatial scale with the objective of producing vegetation descriptions suitable for climate modelling. The REVEALS model was applied on 636 pollen records from lakes and bogs to reconstruct the past cover of 25 plant taxa grouped into 10 plant-functional types and three land-cover types [evergreen trees, summer-green (deciduous) trees, and open land]. The model corrects for some of the biases in pollen percentages by using pollen productivity estimates and fall speeds of pollen, and by applying simple but robust models of pollen dispersal and deposition. The emerging patterns of tree migration and deforestation between 6k bp and modern time in the REVEALS estimates agree with our general understanding of the vegetation history of Europe based on pollen percentages. However, the degree of anthropogenic deforestation (i.e. cover of cultivated and grazing land) at 3k, 0.5k, and 0.2k bp is significantly higher than deduced from pollen percentages. This is also the case at 6k in some parts of Europe, in particular Britain and Ireland. Furthermore, the relationship between summer-green and evergreen trees, and between individual tree taxa, differs significantly when expressed as pollen percentages or as REVEALS estimates of tree cover. For instance, when Pinus is dominant over Picea as pollen percentages, Picea is dominant over Pinus as REVEALS estimates. These differences play a major role in the reconstruction of European landscapes and for the study of land cover-climate interactions, biodiversity and human resources. PMID:25204435
Trondman, A-K; Gaillard, M-J; Mazier, F; Sugita, S; Fyfe, R; Nielsen, A B; Twiddle, C; Barratt, P; Birks, H J B; Bjune, A E; Björkman, L; Broström, A; Caseldine, C; David, R; Dodson, J; Dörfler, W; Fischer, E; van Geel, B; Giesecke, T; Hultberg, T; Kalnina, L; Kangur, M; van der Knaap, P; Koff, T; Kuneš, P; Lagerås, P; Lata?owa, M; Lechterbeck, J; Leroyer, C; Leydet, M; Lindbladh, M; Marquer, L; Mitchell, F J G; Odgaard, B V; Peglar, S M; Persson, T; Poska, A; Rösch, M; Seppä, H; Veski, S; Wick, L
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
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
A study was performed with 2 broiler genotypes (slow and medium growth) restricted in supplementary feed and foraging 2 different mixed vegetations (grass/clover or chicory) to identify possible benefits of herbage on nutrition during the finishing period (80 to 113 d of age). Three hundred birds were included in a 2 × 2 factorial design with groups of 25 birds replicated 3 times. The use of outdoor areas, performance, and forage intake were investigated. To identify possible differences in foraging activity, the use of the range was monitored one day per week at 4 different times of the day. Feed intake from foraging was estimated by killing 4 birds per plot (2 males and 2 females) in the morning and in the evening on 3 d during the experiment and measuring crop content. Vegetation type did not influence broiler use of the free-range area, feed intake, or performance. Differences in the use of the range area, activity level, and feed content in the crops were observed in relation to genotype, sex, age of broilers, and also the time of day. Foraging activity was positively correlated with age. Medium-growth broilers spent more time inside and closer to the broiler houses during the day with increased foraging activity during evenings, in contrast to the slow-growing broilers that showed a more uniform activity during the day. Based on the measurement of crop content it was estimated that the slow-growing genotype had a daily intake of 5 to 8 g of forage per day, whereas the medium-growing genotype had an intake of 9 g for females and 20 g for males. In conclusion, limitation of supplemented protein feed in the finishing period may be acceptable for broilers that have access to highly nutritious vegetation.
Almeida, Gustavo Fonseca; Hinrichsen, Lena Karina
Full Text Available Biomass burning in Northern Ghana is a major cause for concern because of its potential contribution to global warming, hence climate change. This study assessed the emission of trace gases from human activities in the Guinea savanna of Northern Ghana using the guidelines of the Intergovernmental Panel on Climate Change. Carbon content of biomass was determined from four different vegetation covers in the study area; namely, widely open savanna woodland, grass/herb with scattered trees, open savanna woodland and closed savanna woodland. Under each vegetation cover, five plots (1 m x 1 m were demarcated for the estimation of above-ground biomass density. Using the combustion furnace method, emitted carbon, methane and carbon monoxide were estimated. Results showed that the emitted methane (CH4 and carbon monoxide (CO differed significantly (p<0.05 under all the vegetation types. The gases were in perfect correlation (r=1.00 with the quantity of above-ground biomass density and carbon released, with more CO being emitted. Emission of CH4 and CO per hectare of burnt area in the open savanna woodland category was the highest with 0.001719 ton and 0.045119 ton respectively. Over time, emission of these gases may increase their atmospheric concentration, causing major health problems. The contribution to global warming, thus climate change, may also become quite significant. This underscores the fact that existing flaws in the wild fire management policy of Ghana must be effectively dealt with and appropriately implemented with regular reviews to reduce the annual wild fires that are very rampant in Northern Ghana, especially during the dry season.
Full Text Available The present investigation was carried out in Val Visdende (north-eastern Italian Alps on a surface of 1108 ha, with the aim of identifying the most important pasture vegetation types. Based on the conditions observed in the area, main parameters concerning topographic, ecological and management conditions were evaluated and expressed using synthetic indexes. Cluster and principal component analyses were used for the interpretation of the distribution of pasture types in relation to ecological factors, allowing to formulate hypotheses on the evolution of pasture vegetation as a function of ecological and management parameters.
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.
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.
SCOPE: Type 2 diabetes is a multifactorial disease associated with increased oxidative stress, which may lead to increased DNA damage. The aim of this study was to investigate the effect of a healthy diet on DNA oxidation in diabetics and nondiabetics. METHODS AND RESULTS: Seventy-six diabetic and 21 nondiabetic individuals participated in this study. All subjects received information about the benefits of a healthy diet, while subjects randomly assigned to the intervention group received additionally 300 g of vegetables and 25 mL PUFA-rich plant oil per day. DNA damage in mononuclear cells (Comet Assay), urinary excretion of 8-oxo-7-hydro-2'-deoxyguanosine (8-oxodG) and 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and glycated hemoglobin (HbA1c) were measured at baseline, after 4, 8 (end of intervention), and 16 weeks. The intervention with vegetables and PUFA-rich oil led to a significant increase in plasma antioxidant concentrations. Diabetic individuals of the intervention group showed a significant reduction inHbA1c and DNA strand breaks. Levels of HbA1c were also improved in diabetics of the information group, but oxidative damage to DNA was not altered. Urinary 8-oxodG and 8-oxoGuo excretion remained unchanged in both groups. CONCLUSIONS: This study provides evidence that a healthy diet rich in antioxidants reduces levels of DNA strand breaks in diabetic individuals.
Müllner, Elisabeth; Brath, Helmut
Mapping accurately community type is one of main challenges for monitoring semi-arid grasslands with remote sensing. Multi-angle approach has been proved useful for mapping vegetation types in desert. Multi-angle Imaging Spectro-Radiometer (MISR) provides 4 spectral bands and 9 angular observations....
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.
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.
Full Text Available A research about nitrogen–use efficiency (NUE and trees identification was conducted at different vegetation type at Cikaniki, Halimun-Salak National Park, West Java. Plot quadrate methods (20 x 50 m was used to analyze trees vegetation and Kjeldahl methods was used to analyze leaf nitrogen. The width and length of the leaf was also measured to obtain the leaf surface area. The result showed that there are 61 individual trees which consisted of 24 species was identified. The species which have 5 highest important value are Altingia excelsa (64,657, Castanopsis javanica (39,698, Platea latifolia (27,684, Garcinia rostrata (21,151, and Schima walichii (16,049. Futhermore Eugenia lineata (13,967, Melanochyla caesa (12,241, Quercus lineata (10,766, platea excelsa (10,766 have lower important value. Other trees have important value less than 10. Morphological and nitrogen content analyze were done on 4 species : Quercus lineata, G. rostrata, A. excelsa, and E. lineata. Among them, Quercus lineata has highest specific leaf area (SLA (0,01153, followed by G. rostrata (0,00821, A. excelsa (0,00579, and E. lineata (0,00984 g/cm2. The highest number of stomata was found on A. excelsa (85,10/mm2, followed by E. lineata (74,40/mm2, Q. lineata (53,70/mm2, and G. rostrata (18,4 /mm2. The emergent species (A. excelsa and Q. lineata have higher nitrogen content than the underlayer species (G. rostrata and E. lineata. A. excelsa have highest nitrogen use efficiency (28,19% compare to E. lineata (23,81% , Q. lineata (19,09%, and G. rostrata (14,87%. Although not significant, emergen species have higher NUE than underlayer species.
Full Text Available SciELO Venezuela | Language: Spanish Abstract in spanish Esta investigación tuvo como objetivos identificar y cuantificar residuos de los plaguicidas organoclorados (POC) hexaclorobenceno (HCB), lindano, cis-clordano, heptacloro, aldrín, dieldrín, endrín y o,p’-diclorodifeniltricloroetano (o,p’-DDT) en aceites de maíz, soya, girasol y mezclas de aceites, [...] que se expenden en la ciudad de Maracaibo, Venezuela. Se analizaron 30 muestras de 4 tipos de aceites de 10 marcas comerciales. La extracción de residuos de POC se realizó según la técnica de la AOAC. Para la identificación y cuantificación se utilizó un cromatógrafo de gases con detector de captura electrónica (GC-ECD), y para la confirmación, un cromatógrafo de gases acoplado a un espectrómetro de masas (GCMS). Todos los residuos de POC investigados fueron detectados en las muestras analizadas. Se detectaron en mayor concentración (mg/ g) aldrín (0,0088), lindano (0,0054) y o,p’-DDT (0,0035). El análisis estadístico demostró diferencias significativas (P Abstract in english The present study had as objectives to identify and to quantify organochlorine pesticide residues (OCP) hexachlorobenzene (HCB), lindane, cis-chlordane, heptachlor, aldrín, dieldrín, endrín and o,p’-DDT in vegetable oils of corn, soybean, sunflower and mixtures of oils, sold in the city of Maracaibo [...] , Venezuela. 30 samples of 4 types of vegetable oils of 10 commercial brands were analyzed. The extraction of OCP residues was done according to the Official Method of AOAC. A gas chromatograph with an electronic capture detector (GC-ECD) was used for identification and quantification of OCP residues and confirmation was done with a gas chromatograph coupled with a mass spectrometer (GC-MS). All the OCP residues investigated were detected in the analyzed samples. Aldrin (0.0088), lindane (0.0054) and o,p’-DDT (0.0035) were the OCP residues detected in higher concentrations (mg/g). The statistical analysis showed significant differences (P
María, Piñero González; Pedro, Izquierdo Córser; María, Allara Cagnasso; Aiza, García Urdaneta.
Outbreaks of nuisance cyanobacterial bloom are predicted to occur frequently under the effect of severe eutrophication in the water body of Lake Dianchi since the 1990s. Riparian buffers are now well recognized for their roles in the removal of inorganic nitrogen mainly via denitrification. Little is known, however, about the mechanisms of nitrate removal in the riparian buffers of Lake Dianchi. We investigated the wet and dry seasonal dynamics of denitrification rate (DNR) in the soil profiles along the topographic gradient in three riparian buffers with different vegetation types (i.e. forest, open forest, and grass). A strong vertical pattern was observed in soil organic C and N concentrations (i.e. total N, DON, NO3-N, and NH4-N) along the soil layers. We also found significantly higher in situ denitrification activity in the upper horizon along each topohydrosequence while the activities of soil denitrification could be detected down to deeper soil horizons (0.1 to 0.8 mg N per kg dry soil per day), which may contribute significantly to the reduction of the ground water nitrate. Meanwhile, the DNR in the zones near the lake was significantly higher than that in zones near the border with the upland terrace, and also in the wet seasons than in dry seasons. Denitrification rates in the forest, open forest and grass sites were significantly different only in wet seasons. Especially, we found soil organic C had a strong correlation with denitrification in all sites, despite the large intersite variability of soil and vegetation. Our data suggested spatial heterogeneity of substrate availability along a hydrologic and topographic gradient can be the primary control on spatial-seasonal patterns of denitrification in riparian buffers. PMID:23525252
Wang, Shaojun; Cao, Zilin; Li, Xiaoying; Liao, Zhouyu; Hu, Binghui; Ni, Jie; Ruan, Honghua
Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. However, there still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 80 site-years for 57 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SRMAT, irrespective of the type of ecosystem and biome. This is theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SRMAT corrected for a factor related to P/PET. Our finding indicates that it can be sufficient to measure SRMAT for obtaining a well constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatial resolution of a major component of the global carbon cycle.
Full Text Available Soil respiration (SR constitutes the largest flux of CO2 from terrestrial ecosystems to the atmosphere. There still exist considerable uncertainties as to its actual magnitude, as well as its spatial and interannual variability. Based on a reanalysis and synthesis of 72 site-years for 58 forests, plantations, savannas, shrublands and grasslands from boreal to tropical climates we present evidence that total annual SR is closely related to SR at mean annual soil temperature (SR MAT, irrespective of the type of ecosystem and biome. This convergence is to be theoretically expected for non water-limited ecosystems within most of the globally occurring range of annual temperature variability and sensitivity (Q10. We further show that for seasonally dry sites where annual precipitation (P is lower than potential evapotranspiration (PET, annual SR can be predicted from wet season SR MAT corrected for a factor related to P/PET. Our finding indicates that it is sufficient to measure SR MAT for obtaining a highly constrained estimate of its annual total. This should substantially increase our capacity for assessing the spatial distribution and interannual variation of soil CO2 emissions across ecosystems, landscapes and regions, and thereby contribute to improving the spatio-temporal resolution of a major component of the global carbon cycle.
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.
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...
In this study, effect of fatty acid composition on dynamic and steady shear rheology of oils was studied. For this aim, different types of vegetable oils (soybean, sunflower, olive, hazelnut, cottonseed and canola), were used. Rheological properties of oil samples were identified by rheometer (Thermo-Haake) at 25°C and fatty acid composition of oils was determined by GC (Agilent 6890). Steady shear rheological properties of oil samples were measured at shear rate range of 0.1-100 s?¹. Viscosity of olive, hazelnut, cottonseed, canola, soybean and sunflower was 61.2 mPa.s, 59.7 mPa.s, 57.3 mPa.s, 53.5 mPa.s, 48.7 mPa.s and 48.2 mPa.s, respectively. There was a significant difference between viscosity of oils except soybean and sunflower. As a result it was seen that there was a correlation between viscosity and monounsaturated (R=0.89), polyunsaturated (R=-0.97) fatty acid composition of oils, separately. Equation was found to predict viscosity of the oils based on mono and polyunsaturation composition of oils. In addition the dynamic rheological properties of oils were also examined. G', G'' and tan ? (G''/G') values were measured at 0.3 Pa (in viscoelastic region) and 0.1-1 Hz. As a result of multiple regression analysis another equations were found between tan ?, viscosity and polyunsaturated fatty acids. PMID:22450119
Yalcin, Hasan; Toker, Omer Said; Dogan, Mahmut
The Kaidu River originates from the central southern slopes of the Tian Shan from where it flows through the Yulduz Basin and the Yanqi Basin into Lake Bosten. There has been intensive agricultural development along the Kaidu River in the Yanqi Basin. Corn and pepper are two of the main crops. Here, we present a study includes comparisons of soil organic carbon (SOC) between typical native vegtation types (e.g., Glycyrhiza uralensis Fisch, Achnatherum splendens and Sophora alopecuroides Linn) and agricultural crops (i.e., corn and pepper). Fourteen soil pits were sampled at five depths (0-5, 5-15, 15-30, 30-50 and 50-100 cm) in August 2010 (Figure 1). Soil organic matter are determined using the traditional Walkley and Black method and Loss-on-ignition at 375°C for 17 hours. As expected, agricultural soils contain higher SOC than non-agriculatural lands. Native vegetation has various effects on vertical distribution of SOC. We discuss how root system influences SOC dynamics along the Kaidu River in the central Xinjiang, China. Fig. 1. Map of sampling sites along the Kaidu River in northwestern China.
Wang, J.; Wang, X.; Wang, W.
NatureServe (formerly The Nature Conservancy) has posted this publication on their Website. Entitled "Seeing the Forest and the Trees: Ecological Classification for Conservation," it provides in-depth information on the types of natural vegetation encountered across the US landscape.
Stable carbon isotopes (?13C) from bone collagen in leporids provide high-resolution vegetation reconstruction. Leporids [e.g., cottontails (Sylvilagus sp.), jackrabbits (Lepus sp.)] die young (ca. 2 years) and use small home ranges (rabbits. These data suggest a significant increase in C3 plants in leporid diet, and by extension a relative increase in these plant types in the local environment sampled by leporids. This shift is consistent with historic accounts of more C3 mesquite, possibly because of historic land use and ranching practices in the 1800s. However, while this shift may have been accelerated by historic land use changes, our data suggest that the vegetation shift began several hundred years earlier during the prehistoric period. The prehistoric collagen isotopic record also shows increased sample variability through time in both species, suggesting that year-to-year variability in vegetation may have increased late in that sequence. Our results, then, clearly show the potential of leporids for high resolution tracking of vegetation shifts. As leporids are common in paleontological and archaeological sites throughout the temperate zones, their use as a vegetation and climate proxy has wide application.
Mauldin, R. P.; Munoz, C.; Kemp, L.; Hard, R.
Ro?. 14, ?. 3 (2011), 316-325. ISSN 1402-2001 R&D Projects: GA ?R(CZ) GAP505/11/0256 Institutional research plan: CEZ:AV0Z60050516 Keywords : primary succession * relief types * vegetation mapping Subject RIV: EH - Ecology, Behaviour Impact factor: 1.678, year: 2011
Ujházy, K.; Fanta, J.; Prach, Karel
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 popula...
Pavey Scott A; Jg, Sutherland Ben; Leong Jong; Robb Adrienne; von Schalburg Kris; Hamon Troy R; Koop Ben F; Nielsen Jennifer L
The relationship between tourism development and vegetated landscapes is analyzed for the Luya Mountain Nature Reserve (LMNR), Shanxi, China, in this study. Indices such as Sensitive Level (SL), Landscape Importance Value (LIV), information index of biodiversity (H'), Shade-tolerant Species Proportion (SSP), and Tourism Influencing Index (TII) are used to characterize vegetated landscapes, the impact of tourism, and their relationship. Their relationship is studied by Two-Way Indicator Species Analysis (TWINSPAN) and Detrended Correspondence Analysis (DCA). TWINSPAN gives correct and rapid partition to the classification, and DCA ordination shows the changing tendency of all vegetation types based on tourism development. These results reflect the ecological relationship between tourism development and vegetated landscapes. In Luya Mountain Nature Reserve, most plant communities are in good or medium condition, which shows that these vegetated landscapes can support more tourism. However, the occurrence of the bad condition shows that there is a severe contradiction between tourism development and vegetated landscapes. PMID:16027998
Cheng, Zhan-Hong; Zhang, Jin-Tun
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
The paper describes procedure and results of ecological interface for monitoring of drum-separator at RBMK-type NPP. Trial operation has been carried out during four months at the full scope simulator of the leningrad NPP with participation of the licensed control room operators. The results from the trial operation demonstrate that ecological interface considerably increases efficiency of operator activity and essentially reduces protection activation rate caused by errors or untimely actions of operator compared to conventional human-machine interface
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.
Since phenotypic methods to identify coagulase negative staphylococci (CNS) from the milk of ruminants often yield unreliable results, methods for molecular identification based on gene sequencing or fingerprinting techniques have been developed. In addition to culture-based detection of isolates, culture-independent methods may be of interest. On the basis of molecular studies, the five CNS species commonly causing intramammary infections (IMI) are Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus simulans and Staphylococcus xylosus. Current knowledge suggests that S.?chromogenes is a bovine-adapted species, with most cases of IMI due to this bacterium being opportunistic. S.?haemolyticus also appears to be an opportunistic pathogen, but this bacterium occupies a variety of habitats, the importance of which as a source of IMI remains to be elucidated. S.?xylosus appears to be a versatile species, but little is known of its epidemiology. S.?epidermidis is considered to be a human-adapted species and most cases of IMI appear to arise from human sources, but the organism is capable of residing in other habitats. S.?simulans typically causes contagious IMI, but opportunistic cases also occur and the ecology of this bacterium requires further study. Further studies of the ecology and epidemiology of CNS as a cause of IMI in cattle are required, along with careful attention to classification of these bacteria and the diseases they cause. PMID:25467994
Vanderhaeghen, Wannes; Piepers, Sofie; Leroy, Frédéric; Van Coillie, Els; Haesebrouck, Freddy; De Vliegher, Sarne
Question: How can the U.S. National Vegetation Classification (USNVC) serve as an effective tool for classifying and mapping vegetation, and inform assessments and monitoring? Location: Voyageurs National Park, northern Minnesota, U.S.A and environs. The park contains 54 243 ha of terrestrial habitat in the sub-boreal region of North America. Methods: We classified and mapped the natural vegetation using the USNVC, with 'alliance' and 'association' as base units. We compiled 259 classification plots and 1251 accuracy assessment test plots. Both plot and type ordinations were used to analyse vegetation and environmental patterns. Color infrared aerial photography (1:15840 scale) was used for mapping. Polygons were manually drawn, then transferred into digital form. Classification and mapping products are stored in publicly available databases. Past fire and logging events were used to assess distribution of forest types. Results and Discussion: Ordination and cluster analyses confirmed 49 associations and 42 alliances, with three associations ranked as globally vulnerable to extirpation. Ordination provided a useful summary of vegetation and ecological gradients. Overall map accuracy was 82.4%. Pinus banksiana - Picea mariana forests were less frequent in areas unburned since the 1930s. Conclusion: The USNVC provides a consistent ecological tool for summarizing and mapping vegetation. The products provide a baseline for assessing forests and wetlands, including fire management. The standardized classification and map units provide local to continental perspectives on park resources through linkages to state, provincial, and national classifications in the U.S. and Canada, and to NatureServe's Ecological Systems classification. ?? IAVS; Opulus Press.
Faber-Langendoen, D.; Aaseng, N.; Hop, K.; Lew-Smith, M.; Drake, J.
The Federal Geographic Data Committee (FGDC) Vegetation Subcommittee, the Ecological Society of America Panel on Vegetation Classification, and NatureServe have worked together to develop the United States National Vegetation Classification (USNVC). The current standard was accepted in 2008 and fosters consistency across Federal agencies and non-federal partners for the description of each vegetation concept and its hierarchical classification. The USNVC is structured as a dynamic standard, where changes to types at any level may be proposed at any time as new information comes in. But, because much information already exists from previous work, the NVC partners first established methods for screening existing types to determine their acceptability with respect to the 2008 standard. Current efforts include a screening process to assign confidence to Association and Group level descriptions, and a review of the upper three levels of the classification. For the upper levels especially, the expectation is that the review process includes international scientists. Immediate future efforts include the review of remaining levels and the development of a proposal review process.
Franklin, S.B.; Faber-Langendoen, D.; Jennings, M.; Keeler-Wolf, T.; Loucks, O.; Peet, R.; Roberts, D.; McKerrow, A.
The bioaccumulation of current use pesticides (CUPs) and stable isotopes of carbon and nitrogen were investigated in vegetation-caribou-wolf food chain in the Bathurst region (Nunavut, Canada). Volumetric bioconcentration factors (BCF(v)) in vegetation were generally greatest for dacthal (10-12)???endosulfan sulfate (10-11)?>?ß-endosulfan (>9.0-9.7)???pentachloronitrobenzene (PCNB; 8.4-9.6)?>??-endosulfan (8.3-9.3)?>?chlorpyrifos (8.0-8.7) >chlorothalonil (7.6-8.3). The BCF(v) values in vegetation were significantly correlated with the logarithm of the octanol-air partition coefficients (log?K(OA)) of CUPs (r(2) ?=?0.90, p?=?0.0040), although dacthal was an outlier and not included in this relationship. Most biomagnification factors (BMFs) for CUPs in caribou:diet comparisons were significantly less than 1. Similarly, the majority of wolf:caribou BMFs were either significantly less than 1 or were not statistically greater than 1. Significant trophic magnification factors (TMFs) were all less than 1, indicating that these CUPs exhibit trophic dilution through this terrestrial food chain. The log K(OA) reasonably predicted bioconcentration in vegetation for most CUPs but was not correlated with BMFs or TMFs in mammals. Our results, along with those of metabolic studies, suggest that mammals actively metabolize these CUPs, limiting their biomagnification potential despite entry into the food chain through effective bioconcentration in vegetation. PMID:24975230
Morris, Adam D; Muir, Derek C G; Solomon, Keith R; Teixeira, Camilla; Duric, Mark; Wang, Xiaowa
We are concerned with two important issues in simulation modelling: model comprehension and model construction. Model comprehension is limited because many important choices taken during the modelling process are not documented. This makes it difficult for models to be modified or used by others. A key factor hindering model construction is the vast modelling search space which must be navigated. This is exacerbated by the fact that many modellers are unfamiliar with the terms and concepts catered to by current tools. The root of both problems is the lack of facilities for representing or reasoning about domain concepts in current simulation technology. The basis for our achievements in both of these areas is the development of a language with two distinct levels; one for representing domain information, and the other for representing the simulation model. Of equal importance, is the fact that we make formal connections between these two levels. The domain we are concerned with is ecological modelling. This language, called Elklogic, is based on the typed lambda calculus. Important features include a rich type structure, the use of various higher order functions, and semantics. This enables complex expressions to be constructed from relatively few primitives. The meaning of each expression can be determined in terms of the domain, the simulation model, or the relationship between the two. We describe a novel representation for sets and substructure, and a variety of other general concepts that are especially useful in the ecological domain. We use the type structure in a novel way: for controlling the modelling search space, rather than a proof search space. We facilitate model comprehension by representing modelling decisions that are embodied in the simulation model. We represent the simulation model separately from, but in terms of a domain mode. The explicit links between the two models constitute the modelling decisions. The semantics of Elklogic enables English text to be generated to explain the simulation model in domain terms.
The National Ecological Observatory Network (NEON) is a national-scale research platform for documenting and analyzing the impacts of climate change, land-use change, and invasive species on ecology. NEON features sensor networks and experiments linked by cyberinfrastructure to record and archive ecological data for at least 30 years. NEON partitions the United States into 20 ecoclimatic domains. Each domain hosts one fully instrumented core site in a wildland area and two re-locatable sites, which aims to capture ecologically significant gradients (e.g. landuse). Using standardized protocols and an open data policy, NEON data will be gathered from the level of the gene and organism to populations and communities, with extrapolations to the continental scale. In conjunction with environmental data, NEON will conduct field observations and analyses of biological specimens to track biodiversity, population dynamics, productivity, phenology, infectious disease, biogeochemistry and ecohydrology. Here we present a few examples of the type of research NEON will enable using this data. The NEON network will measure and scale many environmental factors that affect vegetation, e.g. temperature, precipitation, and nutrient availability. Direct monitoring of vegetation will enable the study of acclimatory and adaptive changes in vegetation properties over different time scales. Such data will improve the representation of vegetation responses to environmental change in models. The vision behind NEON aims to advance our ability to quantitatively predict ecological change.
Martin, P. H.; Kao, R.; Gibson, C.
The transmission of variation from protoplast-derived plants of tetraploid potato cultivar 'Bintje' to tuber progeny was examined. The morphological alterations of a majority of the variant protoclones were transmitted to corresponding tuber progeny. Some of the normal and variant protoclones gave new phenotypes, or segregated into parental and new phenotypes after vegetative propagation. The ploidy levels of almost all these clones remained unchanged after propagation. It was concluded that the occurrence of variation after vegetative propagation was due to somatic segregation of chimeras resulting from gene mutations or chromosome structural rearrangements in only part of the regenerated plant. The origin of variation is discussed in the light of these results. PMID:24257823
Ramulu, K S; Dijkhuis, P; Roest, S
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 Knys...
Thomas Hecht; Lockyear, Jacqueline F.; Teske, Peter R.; Horst Kaiser
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....
Mvitu M; Longo-Mbenza B; Tulomba D; Nge A
Full Text Available Abstract Backgrounds Tension-type headache is a common psychosomatic disease. However, diurnal variation of headache is yet to be clarified, perhaps due to the lack of an appropriate method to investigate it. Like other painful diseases, it would be helpful to know if there is diurnal variation in tension-type headaches, both for managing headaches and understanding their pathophysiology. The aim of this study was to determine if there is diurnal variation in the intensity and exacerbation of tension-type headache. Methods Patients (N?=?31 with tension-type headache recorded for one week their momentary headache intensity several times a day and their acute headache exacerbations using a watch-type computer as an electronic diary (computerized ecological momentary assessment. Multilevel modeling was used to test the effects of time of day on momentary headache intensity and on the occurrence of acute exacerbations. Results A significant diurnal variation in momentary headache intensity was shown (P?=?0.0005, with the weakest headaches in the morning and a peak in the late afternoon. A between-individual difference in the diurnal pattern was suggested. On-demand medication use was associated with a different diurnal pattern (P?=?0.025, suggesting that headache intensity decreases earlier in the evening in subjects who used on-demand medication, while headache subtype, prophylactic medication use, and sex were not associated with the difference. The occurrence of acute headache exacerbation also showed a significant diurnal variation, with a peak after noon (P?=?0.0015. Conclusions Tension-type headache was shown to have a significant diurnal variation. The relation to pathophysiology and psychosocial aspects needs to be further explored.
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
Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Estudos recentes indicam que em áreas de Cerrado protegidas das atividades antrópicas ocorre uma evolução estrutural de fitofisionomias abertas para outras mais fechadas, com tendência ao desaparecimento das primeiras. Analisou-se a dinâmica das fisionomias do Cerrado ao longo de 44 anos, na Estação [...] Ecológica de Assis, SP, uma das poucas unidades de conservação do bioma no sudeste do Brasil, com o objetivo de caracterizar e quantificar possíveis tranformações fisionômicas no tempo e no espaço. Protegida de pressões antrópicas por longo tempo, observações de campo têm indicado um adensamento da vegetação em toda a área, rumo a um clímax de estrutura florestal. Para realizar este estudo foram utilizadas aerofotos (1962, 1984 e 1994), imagens "QuickBird" (2006) e reconhecimento de campo. Durante o período compreendido por este estudo, a área ocupada pelas fisionomias campestres foi reduzida de 23% para menos de 1% da área estudada, enquanto, no outro extremo do gradiente fisionômico, a proporção correspondente ao cerradão aumentou de 53% para 91%. O ritmo de adensamento da vegetação não foi o mesmo em toda a área, estando, aparentemente, correlacionado com a posição topográfica e diferenças edáficas. Acreditamos que as fisionomias campestres e savânicas inicialmente existentes eram mantidas em decorrência de pressões antrópicas, que impediam a evolução rumo a um clímax edafo-climático de maior fitomassa. Confirmando o que tem sido observado em outros locais, a proteção contra o fogo e a suspensão de atividades agropastoris possibilitaram uma evolução gradativa das formações abertas (campo, campo cerrado e cerrado típico) para outras mais fechadas (cerrado denso e cerradão), tendendo as primeiras ao desaparecimento, caso não ocorram novos distúrbios. As conseqüências dessas transformações, relacionadas com estratégias de manejo, conservação da biodiversidade e fixação de carbono são discutidas. Abstract in english Recent studies indicate that after protection from human pressures (fire, cattle grazing and agriculture), structural changes occur in the cerrado vegetation, changing open physiognomies into more closed savannas. We analyzed the dynamics of vegetation types along 44 years, at Assis Ecological Stati [...] on, one of the rare conservation units protecting the cerrado biome in the southeastern São Paulo State, Brazil, with the aim of characterizing and quantifying those changes in space and time. Protected against human pressures since a long time, field observations have shown an upgrade of local cerrado physiognomies, through a successional process whose structural climax can be a forest physiognomy, with a continuous arboreal stratum. The dynamics of the vegetation types was analyzed by using aerial photographs (1962, 1984 and 1994), Quick Bird satellite images (2006) and field surveys. During this 44 years period, field physiognomies were reduced from 23% to less than 1% of the total area studied. In the other extreme, woodland savanna increased from 53% to 91% of the area. Changes did not happen at the same rhythm across the area, and that is apparently correlated to microclimate and edaphyc differences. We believe that field and savannic physiognomies initially existing were mostly maintained due to heavy human pressures, constraining the secondary succession towards an edapho-climatic climax of greater biomass. Confirming the observations of cerrado areas elsewhere, protection against fire, cattle grazing and agriculture allowed the evolution of open vegetation types into more closed ones, tending to be locally extinct the first if new disturbances do not occur. Consequences of these changes related to management strategies, biodiversity conservation and carbon sink are discussed.
Eduardo Da Silva, Pinheiro; Giselda, Durigan.
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)
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
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.
Full Text Available The results of inspection of sportsmen of different qualification, specialized in at run on midranges are presented in the article. Classification of the functional states of sportsmen is conducted through the structural-linguistic analysis of ?????????????? of cardiac rhythm. Connection is certain between the level of physical preparedness and type of the vegetative adjusting of cardiac rhythm of athletes of different qualification, specialized in at run on midranges. Possibility of the use of these information is grounded for a sporting selection and prognostication of results of runners on the mean of distance.
Full Text Available After wildfires, burning may induce the occurrence of soil water repellency. Soil water repellency may vary in space and time in function of vegetation, the presence of ash and soil moisture. This study analyzes the evolution of fire-induced soil water repellency in function of these factors, and proposes measures to promote the restoration of fire-affected soils. Burnt and unburnt (control soil plots under pine and shrub from a recently burned area (Gorga, Alicante, SE Spain were established. Three treatments were applied: in some of the plots, the original ash layer was kept on the ground; in a second group, the ash layer was removed for simulating the effects of erosion; finally, in a third group, percolating irrigation was conducted to simulate a possible good input of water into the soil profile after burning, that could occur if the first rains were with high quantity but low intensity. During the dry season, soil moisture content was significantly lower in burned plots due to fire-induced water repellency and reduced vegetation cover. During the wet season, soil moisture decreased in the control unburnt plots due to direct evaporation of water intercepted by vegetation and consumption by roots. Fire increased soil water repellency only in plots under pine. Water repellency decreased during the wet season, disappearing in January and reappearing after declining rainfalls. This baseline recovery of soil water repellency was lower where ash removal was simulated. In unburned plots, seasonal fluctuations were less important. In general, ash removal promotes a rapid reduction of water repellency, since it can induce washing of hydrophobic compounds. Irrigation performed immediately after the fire also contributed to decreased water repellency.
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
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)
Brassica vegetables include some economically interesting crops such as cabbage, broccoli, cauliflower, Brussels sprouts, kale and turnip, which are consumed all over the world. A high intake of Brassica vegetables reduces the risk of age-related chronic illness such as cardiovascular health and other degenerative diseases and reduces the risk of several types of cancer, thanks in part to the antioxidant properties of different compounds. Compared to other vegetables, Brassica vegetables have...
Soengas Ferna?ndez, Mari?a Del Pilar; Sotelo Pe?rez, Tamara; Velasco Pazos, Pablo; Cartea Gonza?lez, Mari?a Elena
Ro?. 201, ?. 2 (2014), s. 383-387. ISSN 1469-8137 Institutional support: RVO:67985939 Keywords : community * interaction * vegetation patterns Subject RIV: EH - Ecology, Behaviour Impact factor: 6.373, year: 2013
Öpik, M.; de Bello, Francesco; Price, J. N.; Fraser, L. H.
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 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
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.
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.
The objective of this study was to assess the effects of base cation (Ca, Mg, K) and phosphorous (P) fertilization on the vascular ground vegetation in mature European beech and sessile oak stands located on acid brown soils. Two types of treatment were applied next to control plots (dolomite lime, dolomite lime + natural phosphate + potassium sulphate). Specific richness, total cover (% ), equitability coefficient as well as the Ecological Group of the ground vegetation were studied. Four ye...
Misson, Laurent; Gaëtan du Bus de Warnaffe,; Jonard, Mathieu
Full Text Available The average temperature of our planet is increasing in past several decades due to emission of global warming gases such as CO2, CH4, etc. in the atmosphere leading to undesirable environmental consequences. Therefore, it is necessary to find a mechanism by which a global warming gas can be removed from the regional atmosphere. In this paper, therefore, we proposed an ecological type nonlinear mathematical model for the removal of a global warming gas CO2 from the regional atmosphere by externally introduced liquid species, which may react with this gas and removed it by gravity. The model consists of three dependent variables namely; the concentration of carbon dioxide, the concentration of externally introduced liquid species and the concentration of particulate matters (secondary species formed due to interaction of carbon dioxide with liquid species. The local and global stability conditions are discussed using Routh-Hurwitz criteria and suitable Lyapunove's function respectively. It is shown, analytically and numerically, that the concentration of carbon dioxide decreases as the rate of introduction of externally introduced liquid species increases.
From 1975 to 1981, the survey was carried out to find out radioecological effects of uranium ore deposits on natural vegetation in Koisan, Korea. The symptoms of spotty and mosaic chlorosis, and necrosis were observed in flowering plants in the areas of uranium ore deposits at Deok-Peung-Ri A, B, and C in Koisan. Although 13 species were found to be chlorosis and necrosis, foliages observed are small and very rare. The features of these symptoms closely resemble those occured by the effects of heavy metals. The amount of transparent radiation throughout the depth of soils from uranium radiation sources decreases exponentially. The mean contents in leaves of spotty and mosaik chlorotic plants, and soils were 1.36?1.53 and 5.3?7.4ppm, respectively
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
Full Text Available SciELO Brazil | Language: English Abstract in portuguese O déficit hídrico influenciou na formação dos vasos da madeira de Croton floribundus ocorrentes em cinco áreas com as seguintes vegetações: Floresta Ombrófila, Floresta Estacional Semidecidual e Cerradão. As variações dos vasos devem-se especialmente ao déficit hídrico e número de meses com déficit [...] hídrico. Vasos de maior diâmetro ocorreram em áreas com maior déficit hídrico, o que pode indicar uma estratégia para otimizar o transporte de água em épocas favoráveis. Vasos com menores diâmetros ocorreram em áreas com menor déficit hídrico, possivelmente influenciados pelas menores temperaturas mínimas e a ocorrência de geadas, que semelhante a seca, causa a embolia dos vasos. Na Estação Ecológica de Caetetus, Floresta Estacional Semidecidual (área com maior déficit de água) observaram-se investimentos em eficiência e segurança, com a ocorrência de vasos de maior diâmetro associados a um dos menores índices de vulnerabilidade e maior proporção de vasos múltiplos de quatro ou mais elementos. Abstract in english In this paper we showed that water deficit affects the wood vessels of Croton floribundus in five areas with different vegetation types: Rain Forest, Semi-deciduous Forest and Woody Savanna. We concluded that variations in the vessels are due especially to water deficit and the number of months with [...] water deficit. Larger diameter vessels occurred in areas with higher water deficit, which may represent a strategy to optimize the water transport in favorable periods. Vessels with smaller diameters occur in areas with lower deficit, which may be related to lower minimum temperatures and frost occurrence, which like drought can cause vessel embolism. In Caetetus Ecological Station, a Semi-deciduous Forest (area of highest water deficit), we observed investments in efficiency and safety, with the occurrence of larger diameter vessels associated with one of the lowest vulnerability indexes and highest proportions of multiple vessels of four or more elements.
Eduardo Luiz, Longui; Diego, Romeiro; Luana Naves, Testoni; Osny Tadeu de, Aguiar; Roque, Cielo Filho; Israel Luiz de, Lima; Sandra Monteiro Borges, Florsheim.
The Tibetan Plateau (TP) has fundamental ecological and environmental significance to China and Asia through its influence on regional and continental climates. In recent years, climate warming has caused unprecedented changes to land surface processes on the TP, which would unavoidably undermine the ecological and environmental functions of the TP. Among the numerous land surface processes potentially impacted by climate warming, the effect of vegetation greenness on surface energy balance is one of the most critical, but has been long ignored. In this study, we investigated the spatial and temporal patterns of land surface albedo (LSA) on the TP and evaluated the vegetation greenness in relation to patterns of LSA. We found that LSA has been decreasing in most of the vegetated grasslands on the TP from 2000 to 2013, as compared to a flat trend for desert area. The regions where LSA has been decreasing were spatially correlated to areas of increased vegetation greenness. Along rising altitude, LSA decreasing rate exhibited an overall decreasing trend. Across the TP, elevated vegetation greenness in grasslands acted as a primary factor pulling down LSA. The driving effects of vegetation greenness on LSA vary with grassland types, as revealed by a more significant relationship between vegetation greenness and LSA for the sparsely vegetated zone (i.e. steppe) than the more densely vegetated zone (i.e. meadow). Furthermore, the driving effect of vegetation greenness on LSA exhibited an obvious dependence on altitude as effects with rising altitude were relatively strong up to 3000 m, then weakened from 3500 m to 5000 m, and then the effects again increased from 5000 to 6000 m. The growing season LSA trend revealed in this study emphasizes the need to give greater attention to the growing season LSA flux in future surface energy balance studies.
Tian, Li; Zhang, Yangjian; Zhu, Juntao
What was the impact of July temperature changes on vegetation patterns during the Lateglacial period in north-west Europe? Chironomid-inferred mean July air temperature estimates (C-Tjul) are proxy temperature records independent of terrestrial vegetation. The relationships between Lateglacial vegetation inferred from pollen percentages and these temperature estimates are explored using data synthesised geographically from 15 sites where both pollen percentages and C-Tjul are published to assess the influence of temperature and of temperature changes on regional vegetation. Direct impacts of temperature on a species involve passing the range limits or realised niche of that species. The Bølling warming allowed vegetation to develop. The Younger Dryas cooling had direct impacts on species and vegetation types that were at a critical ecotone and thus sensitive to change. Precipitation is extremely important and its interaction with temperature controlled most of the vegetation patterns inferred from these NW European pollen data. High precipitation was important in W Norway, whereas aridity in the YD was a controlling factor in N Norway, the Netherlands, and NE Germany. Under constant climate, ecological processes occurred such as immigration, succession, and soil development that resulted in vegetation changes. Biotic interactions were also important, such as the impact of grazing by mega-herbivores during Allerød time in Ireland that may have restricted the development of birch woodland. At the coarse scale of this synthesis, July temperature alone is seen not to be a good predictor of the patterns of pollen percentages and hence of vegetation through the Lateglacial. Rather, it is the interactions of temperature and precipitation, combined with ecological processes that appear to be the major factors influencing Lateglacial palynological and vegetation patterns in NW Europe.
Birks, Hilary H.; Birks, H. John B.
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...
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 system physical, biological, and cultural systems
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.
During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealongiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY2002 to support development of a complete data layer describing riparian vegetation cover types on the Columbia River adjacent to the Hanford Site boundaries. Included with this report are the preliminary riparian vegetation maps and the associated metadata for that GIS layer
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.
Raciel, Cruz-Elizalde; Aurelio, Ramírez-Bautista.
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
Full Text Available Two pot trials were conducted during the period of February 15 – October 15 of 2012 and 2013 seasons at two different locations, to evaluate the effect of soil type, sowing date and diluted seawater irrigation on: germination percentage in the first trial and on both plant vegetation and leaves chemical constituents of moringa (Moringa oleifera, Lam. in the second one. The results showed that, generally, Kafr El-Sheikh area (Agricultural area where clayey soil and Nile River water is available outperformed Balteem area (coastal area where soil is silty clay and seawater is available in most studied characters. Lowest seawater ratios in Moringa oleifera irrigation water gave the best results for germination %, growth characters and some chemical and mineral contents as total green color, leaf protein, total carbohydrates, nitrogen, potassium, calcium and magnessium whereas, the highest ratios gave the best results for phosphorus and sodium contents.
M. A. Hegazi
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
Tricolpites trioblatus Mildenhall and Pocknall was described from Upper Miocene-Pliocene sediments of New Zealand and attributed to the Hebe complex (Scrophulariaceae), which is common in the New Zealand vegetation, especially in montane and subalpine habitats. Pollen in Miocene-Pliocene sediments in central Australia is identified with T. trioblatus, and the depositional situations included shallow lakes, with fresh or brackish waters, sometimes becoming saline. The affinities of T. trioblatus are re-examined in the light of these disparate environments in Australia and New Zealand. It has been found that all the fossil grains examined are more comparable to pollen of Wilsonia, and perhaps Cressa (Convolvulaceae), than to those of the Hebe complex. Wilsonia and Cressa are found in salt marshes, hence affinities with them are ecologically more credible for central Australia. T. trioblatus is found in late Eocene sediments deposited under episodic marine transgressions; an environment likely to stimulate the evolution of new species tolerant to saline conditions. PMID:11035168
Full Text Available A propagação vegetativa de espécies medicinais vem despertando interesse das pesquisas agronômicas, uma vez que se constitui no ponto de partida e em ferramenta básica para qualquer cultivo em escala comercial. Este trabalho objetivou determinar o comprimento de estaca e o tipo de substrato mais adequados para a propagação vegetativa de atroveran. Em condições de casa de vegetação sob nebulização intermitente, foram testados dois comprimentos de estacas (10 e 20cm e três substratos (areia lavada, casca de arroz carbonizada e substrato comercial Plantmax®, em delineamento experimental em blocos casualizados, com quatro repetições e cinco estacas por parcela. Aos trinta e cinco dias, foram avaliados a porcentagem de enraizamento, o comprimento da maior raiz (cm e a biomassa seca das folhas e das raízes (mg. Os resultados indicaram que a propagação vegetativa de atroveran por meio de estaquia é viável, uma vez que o seu enraizamento médio ficou acima de 70%. As mudas de atroveran obtidas de estacas com 20cm apresentaram maior biomassa seca das folhas e das raízes, apesar de o comprimento da estaca não ter afetado a porcentagem de enraizamento e o comprimento da raiz. Os tipos de substrato não proporcionaram efeito sobre o desenvolvimento das estacas de atroveran. Recomenda-se a produção de mudas de atroveran com estacas de 20cm de comprimento, utilizando-se qualquer um dos três substratos testados.The vegetative propagation of medicinal species is in increasing agronomic interest because it is the starting point and a basic tool for any cultivation in commercial scale. The objective of this work was to determine the best shoot cutting length and the best substrate for vegetative propagation of Ocimum selloi. Cuttings were placed in greenhouse conditions under intermittent mist. Two cutting sizes (10 and 20cm and three substrate types (washed sand, carbonized rice hulls and commercial substrate Plantmax® were tested. The experiment was in blocks randomly distributed in four replications and five cuttings for parcel. After thirty five days the percentage of rooting, the length of the bigger root (cm and the leaf and root dry weight (mg were analysed. The results indicated that the vegetative propagation of Ocimum selloi by cuttings is viable, once its mean rooting was over 70%. It was not observed significative interaction within the adopted treatments. The cuttings with 20cm length presented larger leaf and root dry weight but the percentage of rooting and the length of the bigger root was not affected by the cutting lenght. The substrate types did not present effect on the development of the cuttings. The production of Ocimum selloi seedlings is recommended with 20cm length cuttings using any substrate tested.
Larissa Corrêa do Bomfim Costa
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
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))
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 ...
Abo El-lil, A. H.
AIM To assess whether regular Mediterranean diet and regular intake of vegetables may reduce the risk of blindness, cataract, and glaucoma in these type 2 diabetics. METHODS A cross-sectional design was carried out among known black diabetics admitted at the diabetic clinics of Kinshasa, between October 2008 and March 2009. The Mediterranean-style dietary score (MSDPS) was used to characterize a Mediterranean-style dietary pattern in the study population using the Harvard semi quantitative FFQ adapted for Africa. RESULTS Five hundred Type 2 diabetic patients were included in this study (48% of males; 40% aged ?60 years). There was a significant association between blindness, cataract and aging; between blindness (P<0.05), cataract (P<0.05), glaucoma (P<0.05), and physical inactivity; between blindness (P<0.05), cataract (P<0.0001), glaucoma (P<0.01) and high SES, and a very significant association between blindness (P<0.0001), cataract (P<0.0001), glaucoma (P<0.0001) and exposure to sunlight. There was also a significant association between blindness, glaucoma, and male sex. Regular intake of Mediterranean diet, Brassica Rapa, beans, Abelmoschus, Musa acuminata reduced significantly the risk of blindness, cataract and glaucoma. CONCLUSION Regular intake of Mediterranean diet, Brassica Rapa, beans, Abelmoschus, and Musa acuminata may significantly reduce the risk of blindness or its major causes among type 2 diabetes mellitus in Africa. PMID:22762057
Moïse, Mvitu Muaka; Benjamin, Longo-Mbenza; Doris, Tulomba Mona; Dalida, Kibokela Ndembe; Augustin, Nge Okwe
A complex examination of 398 practically healthy children aged 7-16 years living under ecologically unfavourable conditions was fulfilled. The group of comparison consisted of 245 children from Braslav district of Vitebsk region. The peculiarities of the central hemodynamic vegetative regulation were studied. The sympathicotonic type of the vegetative tone as well as lack of sympathetic provision under arterial hypotension were determined to occur more frequently. A reliable reduction of the sympathicoadrenal system activity accompanied by the balance shift with the hormonal part dominating over the mediatory one was considered a possible pathogenic mechanism of the changes revealed
The paper brings results from the research of vegetation in forest geobiocenoses of the Kn?hyn?-?ert?v mlýn National Nature Reserve. The research was made on permanent and complementary research plots. Synthetic phytocoenological tables were presented for six most frequently occurring groups of geobiocoene types only with a brief description of their ecological and chorological character- istics (Sorbi-Piceeta humilia, Sorbi-Piceeta, Abieti-Fageta piceae typica, Fageta abietino-pi- ceosa...
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
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.
The Slovenian karst region and similar types of land are difficult to cultivate and often exposed to the process of being abandoned and overgrown with shrubs, trees, and brushwood. Co-grazing in a mixed group may be a way to optimize the management of sheep and goat flocks in such areas. To obtain more knowledge of the natural behavior of small ruminants, the experiment was designed on pasture in the mountain karst region. The experimental area was divided in 6 paddocks, of which 3 paddocks were covered with grass, herbs, and legumes (i.e., grassy paddock [GP]). In the other 3 paddocks the area was additionally overgrown with hazel, beech trees, and bushes (i.e., woody paddock [WP]). In a mixed flock of 40 Slovenian local sheep breed (Istrian Pramenka) and 10 crossbreed goats (Saanen × Alpine goat), 10 animals per species were focally observed during daylight (0500-2100 h). The natural behavior was scored on 12 d, 2 consecutive days in each of the paddocks. Animals were rotated between 6 paddocks according to the balanced schedule. They stayed at each paddock for 5 or 6 d. Observations started on the third day after moving the animals into a specific paddock, following 2 d of adaptation. The results indicated that botanically diverse paddock together with climate conditions affected the behavior. Goats were grazing more (P conditions where more comfort behavior, that is, autogrooming (both species P environmental conditions in the mountain karst region. PMID:24778331
Bojkovski, D; Štuhec, I; Kompan, D; Zupan, M
We compare the spatial and temporal representation of phytoplankton functional types (pPFTs) in four different Dynamic Green Ocean Models (DGOMs; CCSM-BEC, NEMURO, PISCES and PlankTOM5) to derived phytoplankton distributions from two independent satellite estimates, with a particular focus on diatom distributions. Global annual mean surface biomass estimates for diatoms vary between 0.23 mmol C m-3 and 0.77 mmol C m-3 in the models, and are comparable to a satellite-derived estimate (0.41 mmol C m-3). All models consistently simulate a higher zonal mean diatom biomass contribution in the high latitudes than in the low latitudes, but the relative diatom contribution varies substantially between models with largest differences in the high latitudes (20% to 100% of total biomass). We investigate phytoplankton distribution in terms of annual and monthly mean dominance patterns, i.e. the distribution of locations where a given PFT contributes more than 50% to total biomass. In all models, diatoms tend to dominate large areas of the high latitudes of both hemispheres, and the area of the surface ocean dominated by diatoms is significantly higher in the models than in the satellite estimates. We estimate the realized ecological niches filled by the dominant pPFT at each location as a function of annual mean surface nitrate concentration (NO3), sea surface temperature (SST), and mixed layer depth. A general additive model (GAM) is used to map the probability of dominance of all pPFTs in niche and geographic space. Models tend to simulate diatom dominance over a wider temperature and nutrient range, whereas satellites confine diatom dominance to a narrower niche of low-intermediate annual mean temperatures (annual mean SST niches in different ranges of surface NO3 concentrations. For annual mean diatom dominance, the statistically modelled probability of dominance explains the majority of the variance in the data (65.2-66.6%). For the satellite estimates, the explained deviance is much lower (44.6% and 32.7%). The differences in the representation of diatoms among models and compared to satellite estimates highlights the need to better resolve phytoplankton succession and phenology in the models. This work is part of the marine ecosystem inter-comparison project (MAREMIP).
Vogt, M.; Hashioka, T.; Payne, M. R.; Buitenhuis, E. T.; Le Quéré, C.; Alvain, S.; Aita, M. N.; Bopp, L.; Doney, S. C.; Hirata, T.; Lima, I.; Sailley, S.; Yamanaka, Y.
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
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.
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
Full Text Available 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.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 diversidade 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.
William A. Hoffmann
Newman et al. (2000) addressed some important issues regarding the characterization of species-sensitivity distributions (SSDs) used in ecological risk assessments. A common assumption is that SSDs are log-normal, and this allows data sets to be analyzed by standard parametric me...
Full Text Available A eficiência de um trator para desenvolver esforço tratório depende da interação entre o rodado e o solo, envolvendo um complexo conjunto de fatores: característica do rodado, patinagem, transferência de peso do trator, tipo de solo, umidade, estado de compactação, tipo de cobertura do solo, entre o [...] utros, que proporcionam diferentes condições de trabalho e interferem no desempenho do trator. Assim, conduziu-se o presente trabalho com o propósito de avaliar alguns desses fatores no desempenho de um trator agrícola, em área coberta com diferentes tipos de cobertura vegetal (aveia, ervilhaca, nabo, aveia e nabo e sem cobertura). O trator foi submetido a cargas por meio do acoplamento a um escarificador de arrasto e instrumentado para a obtenção da força de tração, velocidade de deslocamento, patinagem e consumo de combustível sendo os dados armazenados por meio de um sistema de aquisição de dados. A patinagem foi maior onde a massa de matéria seca era maior, porém não influenciou na potência requerida na barra de tração. A melhor eficiência de tração foi obtida nas parcelas sem cobertura. O coeficiente de tração foi maior nos tratamentos com cobertura de aveia, ervilhaca e nabo comparados com a área sem cobertura. Conclui-se que a cobertura do solo interfere na capacidade do trator em desenvolver esforço para tracionar máquinas e implementos e que o tipo de cobertura pode causar mudanças na patinagem e na eficiência tratória. Abstract in english The efficiency of a tractor to draft development depends on the interaction among the wheeled and the soil where it moves and it involves a complex group of factors, such as: characteristic of the tire, slip, the tractor weight transfer, soil type, water texture and soil compactation, type of soil c [...] overing, among others. The aim of this work was to evaluate the acting of an agricultural tractor in an area covered with different types of plants. It was used five types of soil covering (oat, Vicia sativa, turnip, oat and V. sativa together and without cover). A load cell, pulse sensor, flow meters and a system of data acquisition, was used. The slip was larger where the mass of dry matter was larger, even so it didn't influence in the potency requested in the drawbar and in the consumption of fuel. The best traction efficiency was obtained in the portions without covering. The traction coefficient was larger in the treatments with covering of oat, Vicia sativa and turnip, when compared with the area without covering. It is ended that the covering of the soil interferes in the capacity of the tractor in developing effort for pull machines and the covering type can intervene in the slip and tractor efficiency.
Antonio, Gabriel Filho; Suedêmio de L., Silva; Alcir J., Modolo; João C. M. da, Silveira.
Near Infrared Reflectance Spectroscopy (NIRS) is becoming a promising technique in soil analyses. Several studies have demonstrated the ability of NIRS, for rapid and non-destructive technique for the quantification of soil carbon and nitrogen in different ecosystems. We have used this technique for measuring the soil carbon and nitrogen concentrations in soils from different climatic zones (semi arid, dry sub humid and mist sub humid) under different types of vegetation cover. The effects of different soil moisture contents on predicting equations were developed for the quantification of soil carbon and nitrogen. Soil carbon and nitrogen was successfully predicted (R2= 0.90 for carbon and R2= 0.85 for nitrogen) by the equations developed. The standard error of prediction (SEP), standard error of prediction corrected for bias SEP (C) and bias for predicting equations of carbon and nitrogen were 0.73, 0.73, 0.04 and 0.07, 0.07, 0.005, respectively. Our results of soil moisture experiments showed that the equations developed by the NIRS predicted most accurately for carbon and nitrogen in dried soil samples than soils with moisture content. The results of this study showed that NIRS can be used as a rapid and non destructive analytical technique to measure the soil carbon and nitrogen. Key words: Soil carbon, soil nitrogen, NIRS, India, chemometric analysis.
Jesudoss, Dinakaran; Rao, Ks
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.
Over the years, the wetlands covered by Sphagnum in Bibai, Japan have been turning into areas of aridity, resulting in an invasion of Sasa into the bogs. Yet little is known about the methane-cycling microorganisms in such environments. In this study, the methanotrophic, methanogenic, and archaeal community structures within these two types of wetland vegetation were studied by phylogenetic analysis targeting particulate methane monooxygenase (pmoA), methyl coenzyme M reductase (mcrA), and the archaeal 16S rRNA gene. The pmoA library indicated that Methylomonas and Methylocystis predominated in the Sphagnum-covered and Sasa-invaded areas, respectively. The mcrA and 16S rRNA libraries indicated that Methanoregula were abundant methanogens in the Sphagnum-covered area. In the Sasa-invaded area, by contrast, mcrA genes were not detected, and no 16S rRNA clones were affiliated with previously known methanogens. Because the Sasa-invaded area still produced methane, of the various uncultured populations detected, novel euryarchaeotal lineages are candidate methane producers. PMID:21897040
Narihiro, Takashi; Hori, Tomoyuki; Nagata, Osamu; Hoshino, Tamotsu; Yumoto, Isao; Kamagata, Yoichi
The terrestrial biosphere and atmosphere are closely coupled at centennial to millennial timescales. Paleoecological data syntheses clearly show that plant ranges and abundances closely tracked late-Quaternary climate change and taxon responses appear to have been highly individualistic. Biogeographic changes in species composition scale up to alter vegetation structure, which in turn affects terrestrial biogeochemical cycling and the biophysical properties of the land surface (e.g. albedo, surface roughness, partitioning of sensible and latent heat fluxes) which feed back to atmospheric dynamics. These asymmetrically-scaled interactions thus require an understanding of vegetation history across a broad range of ecological levels. Several recent advances are enabling more detailed explorations of past vegetation-atmosphere interactions. First, novel analyses of traditional paleovegetational records (i.e. fossil pollen and plant macrofossils) can extract new kinds of information such as the distribution of biomes and plant functional type densities. Second, an increasing array of high-resolution climate proxy records allow detailed study of vegetation responses to local climate change, and frees paleoecological data from its traditional usage as a paleoclimatic proxy. Third, mechanistic vegetation models coupled to general circulation models generate explicit hypotheses about past atmosphere-vegetation interactions, which can be evaluated against paleoecological datasets. Model experiments have demonstrated the sensitivity of late-Quaternary climate regimes to vegetation distributions, and can tease apart the interactive effects of climate and atmospheric carbon dioxide upon vegetation structure. Promising avenues for future research include: 1) Use of regional climate models to study climate-vegetation interactions at increasingly fine spatial scales. 2) Continued collection of paleoclimatic records to improve our understanding of synoptic climate changes and vegetation response. 3) Syntheses of paleovegetational and paleoclimatic evidence with other fossil records to study the combined impacts of climate and vegetational change upon other ecological communities. 4) Linking phylogeography and vegetation history to understand the effect of late-Quaternary vegetation dynamics upon present-day genetic structure. 5) Finally, continued advances in informatics technology and systematic support for data sharing will amplify progress in all areas.
Williams, J. W.
Full Text Available Neste estudo foi avaliado, sob o ponto de vista do consumidor, o desempenho da seção de hortaliças em três equipamentos varejistas de alimentos em Campo Grande(MS): uma mercearia (quitanda), um supermercado e uma feira-livre. Foi realizada uma pesquisa quantitativo-descritiva com 120 indivíduos, res [...] ponsáveis pelas compras de hortaliças para suas residências. Para tanto, foram investigadas doze variáveis adaptadas das dimensões do modelo SERVQUAL, onde se destacam os atributos do equipamento varejista como higiene e limpeza da loja e exposição dos produtos; capacitação dos funcionários como atendimento e cortesia; e atributos do produto como qualidade, variedade e preço. Os resultados mostram que as compras de hortaliças são realizadas semanalmente, sendo que 80% dos consumidores as realizam em supermercados e 94% em feiras-livres. A feira livre apresentou o melhor desempenho nos atributos em que foi avaliada quando comparada com a quitanda e o supermercado. Esse estudo, também revela que, quanto maior a idade do consumidor, maior sua freqüência de compra. Abstract in english The behavior of the fresh fruits and vegetable produce section was evaluated, under the point of view of the consumer, in three types of food retail stores in Campo Grande, Brazilian southeast: a grocery store ("quitanda"), a supermarket, and an open-air market. A quantitative-descriptive survey was [...] conducted with 120 individuals, responsible for purchasing fresh fruit and vegetable produce for their homes. To accomplish that, twelve variables were investigated and adapted from the parameters used in the SERVQUAL model, in which the attributes of the retail outlet are pointed out, such as store hygiene and cleanliness and manner by which produce is displayed; employee training traits, such as courtesy and helpfulness; and quality, price range, and variety of the produce for sale. The results reveal that shopping for grocery is done weekly; 80% of the shoppers interviewed do their shopping in supermarkets and 94% do theirs in open-air markets. The open-air market had the best results in the attributes for which they were evaluated when compared with the grocery store and the supermarket. The study also points out that the older the shopper the more often he/she does grocery shopping.
Dario de O, Lima-Filho; Anderson S, Hokama; Caroline P, Spanhol.
Full Text Available The behavior of the fresh fruits and vegetable produce section was evaluated, under the point of view of the consumer, in three types of food retail stores in Campo Grande, Brazilian southeast: a grocery store ("quitanda", a supermarket, and an open-air market. A quantitative-descriptive survey was conducted with 120 individuals, responsible for purchasing fresh fruit and vegetable produce for their homes. To accomplish that, twelve variables were investigated and adapted from the parameters used in the SERVQUAL model, in which the attributes of the retail outlet are pointed out, such as store hygiene and cleanliness and manner by which produce is displayed; employee training traits, such as courtesy and helpfulness; and quality, price range, and variety of the produce for sale. The results reveal that shopping for grocery is done weekly; 80% of the shoppers interviewed do their shopping in supermarkets and 94% do theirs in open-air markets. The open-air market had the best results in the attributes for which they were evaluated when compared with the grocery store and the supermarket. The study also points out that the older the shopper the more often he/she does grocery shopping.Neste estudo foi avaliado, sob o ponto de vista do consumidor, o desempenho da seção de hortaliças em três equipamentos varejistas de alimentos em Campo Grande(MS: uma mercearia (quitanda, um supermercado e uma feira-livre. Foi realizada uma pesquisa quantitativo-descritiva com 120 indivíduos, responsáveis pelas compras de hortaliças para suas residências. Para tanto, foram investigadas doze variáveis adaptadas das dimensões do modelo SERVQUAL, onde se destacam os atributos do equipamento varejista como higiene e limpeza da loja e exposição dos produtos; capacitação dos funcionários como atendimento e cortesia; e atributos do produto como qualidade, variedade e preço. Os resultados mostram que as compras de hortaliças são realizadas semanalmente, sendo que 80% dos consumidores as realizam em supermercados e 94% em feiras-livres. A feira livre apresentou o melhor desempenho nos atributos em que foi avaliada quando comparada com a quitanda e o supermercado. Esse estudo, também revela que, quanto maior a idade do consumidor, maior sua freqüência de compra.
Dario de O Lima-Filho
Mapping the structure of the vegetation in study plots is important for several reasons. First, with all the detailed data collected, students easily can lose perspective of the bigger picture; they can get lost in the trees and not see the forest, so to
David D. Glenn
Berkeley and Los Angeles : University of California Press, 2011 - (Simberloff, D.; Rejmánek, M.), 678-679 ISBN 978-0-520-26421-2 Institutional research plan: CEZ:AV0Z60050516 Keywords : clonal growth * vegetative regeneration * mechanical control Subject RIV: EF - Botanics
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
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
This article discusses how all four facets of administrative ecology help dispel the claims about the "impossibility" of the superintendency. These are personal ecology, professional ecology, organizational ecology, and community ecology. Using today's superintendency as an administrative platform, current literature describes a preponderance of…
McGarity, Augustus C., III; Maulding, Wanda
The development of photosynthetic active biomass in different ecological conditions, as indicated by normalized difference vegetation indices (NDVIs) is compared by performing a stratified sampling (based on soil assocations) on data acquired over Indiana. Data from the NOAA-10 AVHRR were collected for the 1987 and 1988 growing seasons. An NDVI transformation was performed using the two optical bands of the sensor (0.58-0.68 microns and 0.72-1.10 microns). The NDVI is related to the amount of active photosynthetic biomass present on the ground. Samples of NDVI values over 45 fields representing eight soil associations throughout Indiana were collected to assess the effect of soil conditions and acquisition date on the spectral response of the vegetation, as shown by the NDVIs. Statistical analysis of results indicate that land-cover types (forest, forest/pasture, and crops), soil texture, and soil water-holding capacity have an important effect on vegetation biomass changes as measured by AVHRR data. Acquisition dates should be selected with condideration of the phenological stages of vegetation. Sampling of AVHRR data over extended areas should be stratified according to physiographic units rather than man-made boundaries. This will provide more homogeneous samples for statistical analysis.
Lozano-Garcia, D. Fabian; Fernandez, R. Norberto; Johannsen, Chris J.
Ro?. 64, ?. 5 (2009), s. 908-918. ISSN 0006-3088 Institutional research plan: CEZ:AV0Z60050516 Keywords : alpine vegetation * gradients * phytosociology Subject RIV: EF - Botanics Impact factor: 0.617, year: 2009
Sekulová, L.; Hájek, Michal
This research is intended to improve our understanding of the role of riparian vegetation in stream morphology by evaluating the effects of vegetation on boundary shear stress, providing insight to the type and density of vegetation required for streambank stability. The resu...
Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as an interim vegetative cover for most sites. This coverage allows for required monitoring of the closure cap for settlement and maintenance activities. The purpose of this five year study was to evaluate plant materials for use on wastes sites after the post-closure care period that are quickly and easily established and economically maintained, retard water infiltration, provide maximum year-round evapotranspiration, are ecologically acceptable and do not harm the closure cap. The results of the study suggest that two species of bamboo (Phyllostachys (P.) bissetii and P. rubromarginata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites after surveillance and maintenance requirements have ceased
A model approach for identifying ecological range sites was applied to high elevation sagebrush-dominated rangelands on Parker Mountain, in south-central Utah. The approach utilizes map information derived from both high altitude color infrared photography and LANDSAT digital data, integrated with soils, geological, and precipitation maps. Identification of the ecological range site for a given area requires an evaluation of all relevant environmental factors which combine to give that site the potential to produce characteristic types and amounts of vegetation. A table is presented which allows the user to determine ecological range site based upon an integrated use of the maps which were prepared. The advantages of identifying ecological range sites through an integrated photo interpretation/LANDSAT analysis are discussed.
Jaynes, R. A.
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
The Ecological Land Classification system was developed to provide a standardized methodology for describing plant communities and wildlife habitat in southern Ontario. The method employs a hierarchical classification system. It can be applied at different levels of accuracy, i.e., at regional, sub-regional, and local scales with an increasing differentiation of vegetation communities. The standardization of the approach permits a comparison of vegetation communities from different sites and an evaluation of the rarity of these communities within the province. Further, the approach facilitates the monitoring of changes in terrestrial communities with time. These characteristics make Ecological Land Classification mapping a useful tool for environmental assessment such as the ones undertaken for the Port Hope and Port Granby Long-Term Waste Management Projects, which were conducted pursuant to the Canadian Environmental Assessment Act 1992. In the context of the Environmental Assessment for the Port Hope and Port Granby Projects, an Ecological Land Classification study was undertaken to characterize the terrestrial environment at regional, local and site levels. Vegetation patches (polygons) were delineated on the basis of air photo interpretation. The individual polygons were then visited for detailed inventory and classified to the most detailed level; that is to the vegetation type. Plant communities were then compared with those listed in the Ontario Natural Heritathose listed in the Ontario Natural Heritage Information Centre database to determine their rarity and to determine where they rank as Valued Ecosystem Components. Ecological Land Classification mapping results were used in the assessment of effects to Valued Ecosystem Components. A spatial analysis of the digitized vegetation maps showed the geographic extent of habitat losses and impairments due to various project works and activities. Landscape rehabilitation strategies and concepts were subsequently developed based on Ecological Land Classification inventory data and predicted effects. (author)
Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O trabalho teve como objetivo avaliar a propagação vegetativa da menta utilizando diferentes tipos de estacas e substratos. O experimento foi conduzido no Horto de Plantas Medicinais da Unimontes, campus Janaúba - MG. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema f [...] atorial 2 x 4 (dois tipos de estacas e quatro diferentes substratos) com quatro repetições, sendo cada parcela representada por seis estacas. Foram analisadas as variáveis comprimento de parte aérea e de raízes, massa seca de parte aérea e de raízes e número total de brotações formadas por planta. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Scott-Knott a 5% de probabilidade. A interação entre os fatores estacas e substratos não foi significativa para as variáveis estudadas, passando-se a estudar o efeito isolado de cada fator. A propagação de Mentha arvensis L. pode ser realizada tanto por estacas apicais como medianas, utilizando o substrato solo + areia + esterco bovino (2:1:1) para a produção de mudas de qualidade. Abstract in english The purpose of the study was to evaluate the vegetative propagation using different types of mint cuttings and substrates. The experiment was conducted in the Garden of Medicinal Plants of Unimontes, in Janaúba - MG. The experimental design was completely randomized (CRD) in 2 x 4 factorial schemes [...] (two types of poles and four different substrates) with four replications and each plot was represented by six cuttings. The variables analyzed were the length of the shoots and roots, the dry matter of the shoots and roots and the total number of shoots per plant. The data were subject to ANOVA and the means were compared by Scott-Knott's test at 5% of probability. The interaction among stem cuttings and substrates was not significant for the variables studied, thus, the isolated effect of each factor was studied. The propagation of Mentha arvensis L. can be performed either by apical cuttings as medians, using the substrate soil + sand + manure bovine (2:1:1) for the production of quality seedlings.
H.T.R, Amaro; J.R, Silveira; A.M.S de S, David; M.A.V de, Resende; J.A.S., Andrade.
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.
Based on the statistical data of natural ecology and social economy in Jinyintan Grassland Scenic Area in Qinghai Province in 2008, an evaluation index system for the ecological sensitivity of this area was established from the aspects of protected area rank, vegetation type, slope, and land use type. The ecological sensitivity of the sub-areas with higher tourism value and ecological function in the area was evaluated, and the tourism function zoning of these sub-areas was made by the technology of GIS and according to the analysis of eco-environmental characteristics and ecological sensitivity of each sensitive sub-area. It was suggested that the Jinyintan Grassland Scenic Area could be divided into three ecological sensitivity sub-areas (high, moderate, and low), three tourism functional sub-areas (restricted development ecotourism, moderate development ecotourism, and mass tourism), and six tourism functional sub-areas (wetland protection, primitive ecological sightseeing, agriculture and pasture tourism, grassland tourism, town tourism, and rural tourism). PMID:20879542
Zhong, Lin-sheng; Tang, Cheng-cai; Guo, Hua
Ro?. 58, ?. 6 (2012), s. 783-792. ISSN 0038-0768 Institutional support: RVO:60077344 Keywords : earthworm * litter * nutrient cycling * soil chemical properties * vegetation switch Subject RIV: EH - Ecology, Behaviour Impact factor: 0.889, year: 2012
Iwashima, N.; Masunaga, T.; Fujimaki, R.; Toyota, Ayu; Tayasu, I.; Hiura, T.; Kaneko, N.
Background/Objectives:Biomarkers for a mixed fruit and vegetable (FV) diet are needed to provide a better understanding of the association between FV intake and type 2 diabetes. We aimed to examine the prospective association between a composite score comprised of three biomarkers of FV intake in free-living populations and incident diabetes.Subjects/Methods:A total of 318 incident diabetes cases and 926 controls from the EPIC (European Prospective Investigation of Cancer)-Norfolk study aged 40-79 years at baseline (1993-1997), completed 7-day prospective food diary and had plasma vitamin C and carotenoid measures. A composite biomarker score (CB-score) comprising the sum of plasma vitamin C, beta-carotene and lutein was derived. Odds ratios (ORs) and 95% confidence intervals (CIs) for incident diabetes were estimated using multivariable logistic regression.Results:A strong inverse association was found between the CB-score and incident diabetes. The ORs (95% CI) of diabetes comparing quartiles Q2, Q3 and Q4 of the CB-score with Q1 (reference category) were 0.70 (0.49, 1.00), 0.34 (0.23, 0.52) and 0.19 (0.12, 0.32), respectively, and 0.49 (0.40, 0.58) per s.d. change in CB-score in a model adjusted for demographic and lifestyle factors. The association was marginally attenuated after additionally adjusting for body mass index and waist circumference (0.60 (0.49 and 0.74) per s.d. change in CB-score).Conclusions:A combination of biomarkers representing the intake of a mixed FV diet was strongly inversely associated with incident diabetes. These findings provide further support for measuring dietary biomarkers in studies of diet-disease associations and highlight the importance of consuming FV for the prevention of diabetes.European Journal of Clinical Nutrition advance online publication, 12 November 2014; doi:10.1038/ejcn.2014.246. PMID:25387899
Cooper, A J M; Sharp, S J; Luben, R N; Khaw, K-T; Wareham, N J; Forouhi, N G
The vegetation of northern Chihuahuan Desert rangelands is sparse, heterogeneous and for most of the year, consists of a large proportion of non-photosynthetic material. The soils in this area are spectrally bright and variable in their reflectance properties. Both factors provide challenges to the application of remote sensing for estimating canopy variables (e.g., leaf area index, biomass, percentage canopy cover, primary production). Additionally, with reference to current paradigms of rangeland health assessment, remotely-sensed estimates of canopy variables have limited practical use to the rangeland manager if they are not placed in the context of ecological site and ecological state. To address these challenges, we created a multifactor classification system based on the USDA-NRCS ecological site schema and associated state-and-transition models to map ecological states on desert rangelands in southern New Mexico. Applying this system using per-pixel image processing techniques and multispectral, remotely sensed imagery raised other challenges. Per-pixel image classification relies upon the spectral information in each pixel alone, there is no reference to the spatial context of the pixel and its relationship with its neighbors. Ecological state classes may have direct relevance to managers but the non-unique spectral properties of different ecological state classes in our study area means that per-pixel classification of multispectral data performs poorly in discriminating between different ecological states. We found that image interpreters who are familiar with the landscape and its associated ecological site descriptions perform better than per-pixel classification techniques in assigning ecological states. However, two important issues affect manual classification methods: subjectivity of interpretation and reproducibility of results. An alternative to per-pixel classification and manual interpretation is object-based image analysis. Object-based image analysis provides a platform for classification that more closely resembles human recognition of objects within a remotely sensed image. The analysis presented here compares multiple thematic maps created for test locations on the USDA-ARS Jornada Experimental Range ranch. Three study sites in different pastures, each 300 ha in size, were selected for comparison on the basis of their ecological site type (';Clayey', ';Sandy' and a combination of both) and the degree of complexity of vegetation cover. Thematic maps were produced for each study site using (i) manual interpretation of digital aerial photography (by five independent interpreters); (ii) object-oriented, decision-tree classification of fine and moderate spatial resolution imagery (Quickbird; Landsat Thematic Mapper) and (iii) ground survey. To identify areas of uncertainty, we compared agreement in location, areal extent and class assignation between 5 independently produced, manually-digitized ecological state maps and with the map created from ground survey. Location, areal extent and class assignation of the map produced by object-oriented classification was also assessed with reference to the ground survey map.
Steele, C. M.; Bestelmeyer, B.; Burkett, L. M.; Ayers, E.; Romig, K.; Slaughter, A.
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
Full Text Available 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.
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
Detailed geographic information system (GIS) studies on plant ecology, animal behavior and soil hydrologic characteristics across spatially complex landscapes require an accurate digital elevation model (DEM). Following interpolation of last return LIDAR data and creation of a LIDAR-derived DEM, a series of 260 points, stratified by vegetation type, slope gradient and off-nadir distance, were ground-truthed using a total laser station, GPS, and 27 interconnected benchmarks. Despite an overall mean accuracy of +2 cm across 8 vegetation types, it created a RMSE (square root of the mean square error) of 1.21 m. DEM elevations were over-estimated within forested areas by an average of 20 cm with a RMSE of 1.05 m, under-estimated (-12 cm, RMSE = 1.36 m) within grasslands. Vegetation type had the greatest influence on DEM accuracy, while off-nadir distance (P = 0.48) and slope gradient (P = 0.49) did not influence DEM accuracy; however, the latter factors did interact (P rangelands as they provide a basis for the development and evaluation of management policies and actions. In this study, LIDAR data were found to be superior to digital classification schedules for their mapping accuracy in aspen forest and grassland, but not shrubland. No single classification schedule created a high classification accuracy map for all types; however, the integration of LIDAR data and digital images achieved maps with corresponding overall accuracies of 91% and 83.9% with 3 and 8 classes of vegetation.
Full Text Available Soil erosion of the Pisha Sandstone area of Loess Plateau is extremely severe in China. The Pisha Sandstone is very hard when it is dry, while it is very frail when wet. The seabuckthorn flexible dam (SFD, a type of ecological engineering, was proposed to control soil erosion and meliorate soil within the Pisha Sandstone area. To assess its effectiveness and the ecological restoration and soil improvement performance, a field experiment was conducted in this area. We found the strong sediment retention capacity of the SFD is the basis of using it to restore the ecosystem. We compared some certain ecological factors and soil quality between a gully with the SFD and a gully without the SFD, including soil moisture, soil organic matter (SOM, soil nutrients (including Ammonia Nitrogen, available phosphorus and Potassium, vegetation coverage and biodiversity. The results showed that the SFD exhibits excellent performance for ecological restoration and soil improvement of this area. The results are as follows: (i by the sediment retention action, the deposition commonly occurred in the SFD gully, and the deposition patterns are obviously different from upper to lower gully, (ii more surprisingly, unlike trees or other shrubs, the seabuckthorn has good horizontal extending capacity by its root system, (iii soil moisture, SOM, soil nutrients, vegetation coverage and biodiversity in the vegetated gully with the SFD are all markedly increased. The results showed the SFD is both effective and novel biological measure for ecological restoration and soil improvement within the Pisha Sandstone area.
F. S. Yang
Soil erosion of the Pisha Sandstone area of Loess Plateau is extremely severe in China. The Pisha Sandstone is very hard when it is dry, while it is very frail when wet. The seabuckthorn flexible dam (SFD), a type of ecological engineering, was proposed to control soil erosion and meliorate soil within the Pisha Sandstone area. To assess its effectiveness and the ecological restoration and soil improvement performance, a field experiment was conducted in this area. We found the strong sediment retention capacity of the SFD is the basis of using it to restore the ecosystem. We compared some certain ecological factors and soil quality between a gully with the SFD and a gully without the SFD, including soil moisture, soil organic matter (SOM), soil nutrients (including Ammonia Nitrogen, available phosphorus and Potassium), vegetation coverage and biodiversity. The results showed that the SFD exhibits excellent performance for ecological restoration and soil improvement of this area. The results are as follows: (i) by the sediment retention action, the deposition commonly occurred in the SFD gully, and the deposition patterns are obviously different from upper to lower gully, (ii) more surprisingly, unlike trees or other shrubs, the seabuckthorn has good horizontal extending capacity by its root system, (iii) soil moisture, SOM, soil nutrients, vegetation coverage and biodiversity in the vegetated gully with the SFD are all markedly increased. The results showed the SFD is both effective and novel biological measure for ecological restoration and soil improvement within the Pisha Sandstone area.
Yang, F. S.; Cao, M. M.; Li, H. E.; Wang, X. H.; Bi, C. F.
This South Florida Restoration Science Forum (SFRSF) site explores how to understand, describe, and predict ecological changes at the landscape and regional levels. Issues discussed include the effects of landscape hydrology on specific animal populations, predicting ecological responses to landscape management, understanding changes in the landscape by studying vegetation patterns, and the Cape Sable Seaside Sparrow's importance to understanding ecological changes. Links are provided for further information.
Brno : Academy of Sciences of the Czech Republic, Institute of Archaeology at Brno, 2009 - ( Šída , P.), s. 30-37 ISBN 978-80-86023-86-1. - (Dolnov?stonické studie. 17) Institutional research plan: CEZ:AV0Z80020508 Keywords : palaeolithic * vegetation * palaeoecology Subject RIV: EH - Ecology, Behaviour
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)
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
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 pape...
Hoffmann, William A.; Franco, Augusto C.
The International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation) was established in 1987. It is led by the UK and has its Programme Coordination Centre at the Centre for Ecology and Hydrology (CEH) in Bangor. It is one of seven ICPs and Task Forces that report to the Working Group on Effects (WGE) of the Convention on Long-range Transboundary Air Pollution (LRTAP Convention) on the effects of atmospheric pollutants on different ...
Harmens, Harry; Mills, Gina; Hayes, Felicity; Norris, David; And, The Participants Of The Icp Vegetation
The International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation) was established in 1987. It is led by the UK and has its Programme Coordination Centre at the Centre for Ecology and Hydrology (CEH) in Bangor. It is one of seven ICPs and Task Forces that report to the Working Group on Effects (WGE) of the Convention on Long-range Transboundary Air Pollution (LRTAP Convention) on the effects of atmospheric pollutants on different components of...
Harmens, Harry; Mills, Gina; Hayes, Felicity; Norris, David; And, The Participants Of The Icp Vegetation
The International Cooperative Programme on Effects of Air Pollution on Natural Vegetation and Crops (ICP Vegetation) was established in 1987. It is led by the UK and has its Programme Coordination Centre at the Centre for Ecology and Hydrology (CEH) in Bangor. It is one of seven ICPs and Task Forces that report to the Working Group on Effects (WGE) of the Convention on Long-range Transboundary Air Pollution (LRTAP Convention) on the effects of atmospheric pollutants on different components of...
Harmens, Harry; Mills, Gina; Hayes, Felicity; Sharps, Katrina; Frontasyeva, Marina; And, The Participants Of The Icp Vegetation
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
Operant performance of non-food deprived rats (n=8) was assessed under progressive ratio (PR) and concurrent PR-fixed ratio schedules of food pellet and/or vegetable shortening reinforcement. Post operant baselines, rats were matched and divided into 2 groups based upon the schedule of shortening availability: High restriction binge group (H, 1-hr home cage shortening access each week on Monday, Wednesday, and Friday) and Low restriction (L, 1-hr shortening access daily). Chow and water were ...
Wojnicki, F. H. E.; Roberts, D. C. S.; Corwin, R. L. W.
Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish Se determinó con el método de análisis de vacíos y omisiones de conservación (GAP), cómo contribuyen las 289 unidades de manejo para la conservación de la vida silvestre (UMA) de Coahuila a la conservación de los tipos de vegetación natural. Mediante un análisis de componentes principales se definió [...] la relación entre los tipos de vegetación de Coahuila, respecto a su representatividad en áreas protegidas (AP). Las UMA en el estado cubren 1,546,778 ha, de ellas 72.6% se localizan, principalmente, en sitios con cuatro tipos de vegetación primaria, que en orden de cobertura son: matorral desértico rosetófilo, matorral espinoso tamaulipeco, matorral desértico micrófilo y pastizal natural. Si se considera a las UMA como elementos equivalentes a las AP en la conservación de la biodiversidad, éstas cubrirían todos los tipos de vegetación que son omisiones de conservación en la red de AP, con excepción de la vegetación gipsófila y la halófila. Sin embargo, no incluirían los cuatro tipos de vegetación, que son a la vez vacíos de conservación en la actual red de AP, las cuales en suma sólo representan 12,514 ha. Las UMA comprenden más del 25% de la extensión del matorral espinoso tamaulipeco y 4 mezquital primarios de Coahuila, actualmente sub-representados en la red de AP de la entidad por lo que éstas, podrían contribuir a la conservación de la biodiversidad, si se manejaran sustentablemente, y de la cobertura natural del suelo. Abstract in english In order to know the way in which the 289 units for management and conservation of wildlife (UMA, according to its initials in Spanish) contribute to the conservation of natural vegetation types of Coahuila, the gap method was used. By the Principal Component Analysis was determined the relationship [...] of the vegetation types of the state in regard to the representativeness in protected areas (PA). The local UMAs cover 1, 546, 778 ha; 72 % of them are found, mainly, in places where the four types of primary vegetation are present, which, according to their extent, would be as follows: desert microphilous scrub, desert rosetophilous scrub, tamaulipean thorn scrub and natural grassland. If UMA would be considered equivalent to PA for biodiversity conservation they would cover five vegetation types which are gaps in current protected areas; however, two plant communities: halophilous vegetation and gypsophilous vegetation would be represented in PA below the reach of the national protected average of Mexico (12%). Moreover, four vegetation types, which represent only 12,514 ha, are not represented neither in PA nor in UMA. Coahuila's UMAs cover 25% of its tamaulipean thorn scrub and mesquite land extension in primary condition, which are currently under-represented in state PA network. That means, UMA can contribute to biodiversity conservation if they are sustainably managed, protecting natural land cover.
César, Cantú Ayala; Fernando, González Saldivar; Patricia, Koleff Osorio; José, Uvalle Sauceda; José G., Marmolejo Monsivais; Jorge, García Hernández; Laura, Rentería Arrieta; Jonás, Delgadillo Villalobos; Cynthia, Resendiz Infante; Edgardo, Ortíz Hernández.
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.
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
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.
Remotely sensed data is increasingly being used by ecologists to answer a wide array of questions in their respective fields. In order to fully take advantage of the potential of these types of data, ecologists should engage actively in the remote sensing problem. To these ends, ecologists can look within their own discipline for a wealth of principles and techniques for integrating remote sensing methodologies in the science they practice. In this dissertation I highlight three general areas in which advances in ecological sciences have the potential to improve remote sensing science, and consequently, result in improved tools for ecological research. These areas are: (1) Physiological ecology; (2) Sampling design and spatial considerations; (3) Species Distribution modeling. In the first chapter I outline an experiment that develops a direct and more mechanistic relationship between passively collected spectral data and plant photosynthetic functioning through the characterization of photochemical and nonphotochemical quenching and its effects on steady-state fluorescence. I found that simple reflectance indices can track heat and water stress induced changes in steady-state fluorescence at the canopy scale. This technique takes advantage of advances in physiological ecology to make remote and rapid measurements of plant stress in real-time. The second and third chapters are case studies in vegetation mapping within the Lake Tahoe Basin and within the American River watershed. In these studies I utilize sample stratification techniques for locating plots in support of the mapping process. Additionally, I incorporate regression based distribution modeling in the mapping process in order to distill the large number of topographic variables available, into ecologically meaningful response surfaces that can be incorporated into the classification problem. I found that incorporating general additive modeling results in the mapping process results in consistent and large improvements in map accuracy. This work provides an avenue for ecologists to incorporate knowledge of species autecology into the classification problem and thus provides for a stronger link between the disciplines of remote sensing and applied vegetation science.
Dobrowski, Solomon Zev
Full Text Available The goal underlying the process of evaluating ecological capability of district 22 of Tehran as the main part of west and north west of Tehran is to realize the potential capability of land within practical application to achieve communication and interaction between human activities, society and the land potential to gain land preparation. To do so, in first place, an area of 5700 hectares, as district 22, was specified, maps of sustainable ecological resources (including physiography, type of soil, type and density of vegetation, geology and petrology and unsustainable resources (including maps for water resources, wild life habitats were prepared. On second stage the maps of land form units by using geographic information system (GIS were provided by the over laying maps of slope, direction and elevation level. The environmental unit maps were prepared by overlapping the soil type and vegetation maps. In the next stage the ecological models of different stratum the environmental information included in the tables were adjusted, coded and were then confirmed with the ecological models of land applications in Iran and the ecological models of different classes of application were prepared for district 22 through a mathematical model and subsequently, the maps of application classes via GIS was prepared. The findings of the ecological potentials of district 22 shows that except the hillside parts, the region has potential classification 2 for urban development. For an outdoor recreation, the entire region is in class 1 (suitable and has first and second potential for indoor recreation. For agriculture and animal husbandry the region has the potential 5 and only in a part of the region due to depth of the soil, it has potential 4 for agricultural and animal husbandry development. The region has potential 4 for supported woods application, the reason of this figure is low amount of water reserve and special physiography of the region.
The role of riparian vegetation in shaping river morphology is widely recognized. The interaction between vegetation growth and riverbed evolution is characterized by complex nonlinear feedbacks, which hinder direct estimates of the role of key elements on the morphological evolutionary trajectories of gravel bed rivers. Adopting a simple theoretical framework, we develop a numerical model which couples hydromorphodynamics with biomass dynamics. We perform a sensitivity analysis considering several parameters as flood intensity, type of vegetation, and groundwater level. We find that the inclusion of vegetation determines a threshold behavior, identifying two possible equilibrium configurations: unvegetated versus vegetated bars. Stable vegetation patterns can establish only under specific conditions, which depend on the different environmental and species-related characteristics. From a management point of view, model results show that relatively small changes in water availability or species composition may determine a sudden shift between dynamic unvegetated conditions to more stable, vegetated rivers.
Bertoldi, Walter; Siviglia, Annunziato; Tettamanti, Stefano; Toffolon, Marco; Vetsch, David; Francalanci, Simona
Two of the most important evolutionary tendencies of vertebrates in islands are the breadening habitat and trophic niche with regards to those relative species that live in continental ecosystems. Therefore, we present two cases related with these phenomenon and their ecological implications in the Canarian Archipelago. Common Raven (Corvus corax) is present in all environments of the Canary Islands where vegetation is highly structured according to altitude creating differnt types of macroha...
Bacterial ecology is concerned with the interactions between bacteria and their biological and nonbiological environments and with the role of bacteria in biogeochemical element cycling. Many fundamental properties of bacteria are consequences of their small size. Thus, they can efficiently exploit very dilute solutions of organic matter and their potential growth rates are very high. Bacteria do not have a cytoskeleton and they are covered by a rigid cells wall. Therefore they can only take up dissolved low-molecular-weight compounds from their surroundings; when bacteria exploit polymeric compounds these must first be undergo extracellular hydrolysis. Bacteria have a great diversity with respect to types of metabolism that far exceeds the metabolic repertoire of eukaryotic organisms. Bacteria play a fundamental role in the biosphere and certain key processes such as, for example, the production and oxidation of methane, nitrate reduction and fixation of atmospheric nitrogen are exclusively carried out by different groups of bacteria. Some bacterial species – ‘extremophiles’ – thrive in extreme environments in which no eukaryotic organisms can survive with respect to temperature, salinity or pH. Key Concepts:Key Concepts: * Fundamental properties of bacteria are related to their small size and lack of cytoskeleton. * Bacteria display a great diversity in types of metabolism. * Bacteria play a key role in the biosphere in terms of transfer of matter and energy. * A number of fundamental biogeochemical processes are carried exclusively by bacteria. * Bacteria play an important role in all types of habitats including some that cannot support eukaryotic life.
Heavy metal (HM) pollution of waters, soils and vegetation is a major ecological problem that needs to be investigated. The present study involved the collection of soil samples and natural vegetations (Tribilas terristris, Lepia nodiflora, Amaranthus viridis, Heliotropium euoropeum, Coronopis didymus, Cynodon ductylon, Chenopodium murale and Eclipta alba) from the vicinity of wastewater canal and subsequent analysis for their HM concentrations. Results showed that HM concentrations varied within the species of vegetation and type of metal analyzed. The order of vegetation for metal concentrations was A. viridis > E. alba > H. euoropeum > L. nodiflora > C. murale > C. didymus > C. ductylon > T. terristris. Metals prevailed in plants in the decreasing order of Fe > Mn > Zn > Pb > Cr > Cu > Cd, irrespective of the vegetation. Metal prevalence in soils was in the order of Fe > Mn > Cd > Cr > Pb > Zn > Cu. Samples near canal were found with higher level of Mn, Pb and Zn as compared to soil away from canal water. Distant sampling gave higher accumulation of Cd, Cr, Cu and Fe as compared to the soil nearby wastewater. The analyzed species of HM in the soils and plants may indicate the variability of their composition in wastewater. (author)
The Velay sequence (France) provides a unique, continuous, palynological record spanning the last four climatic cycles. A pollen-based reconstruction of temperature and precipitation displays marked climatic cycles. An analysis of the climate and vegetation changes during the interglacial periods reveals comparable features and identical major vegetation successions. Although Marine Isotope Stage (MIS) 11.3 and the Holocene had similar earth precessional variations, their correspondence in terms of vegetation dynamics is low. MIS 9.5, 7.5, and especially 5.5 display closer correlation to the Holocene than MIS 11.3. Ecological factors, such as the distribution and composition of glacial refugia or postglacial migration patterns, may explain these discrepancies. Comparison of ecosystem dynamics during the past five interglacials suggests that vegetation development in the current interglacial has no analogue from the past 500,000 years. PMID:16162676
Cheddadi, Rachid; de Beaulieu, Jacques-Louis; Jouzel, Jean; Andrieu-Ponel, Valérie; Laurent, Jeanne-Marine; Reille, Maurice; Raynaud, Dominique; Bar-Hen, Avner
The Velay sequence (France) provides a unique, continuous, palynological record spanning the last four climatic cycles. A pollen-based reconstruction of temperature and precipitation displays marked climatic cycles. An analysis of the climate and vegetation changes during the interglacial periods reveals comparable features and identical major vegetation successions. Although Marine Isotope Stage (MIS) 11.3 and the Holocene had similar earth precessional variations, their correspondence in terms of vegetation dynamics is low. MIS 9.5, 7.5, and especially 5.5 display closer correlation to the Holocene than MIS 11.3. Ecological factors, such as the distribution and composition of glacial refugia or postglacial migration patterns, may explain these discrepancies. Comparison of ecosystem dynamics during the past five interglacials suggests that vegetation development in the current interglacial has no analogue from the past 500,000 years. PMID:16162676
Cheddadi, Rachid; de Beaulieu, Jacques-Louis; Jouzel, Jean; Andrieu-Ponel, Valérie; Laurent, Jeanne-Marine; Reille, Maurice; Raynaud, Dominique; Bar-Hen, Avner
The present study examined the growth characteristics of Alicyclobacillus acidoterrestris DSM 3922 vegetative cells and spores after inoculation into apple, pomegranate and pomegranate-apple blend juices (10, 20, 40 and 80%, v/v). Also, the effect of sporulation medium was tested using mineral [Bacillus acidoterrestris agar (BATA) and Bacillus acidocaldarius agar (BAA)] and non-mineral containing media [potato dextrose agar (PDA) and malt extract agar (MEA)]. The juice samples were inoculated separately with approximately 10(5)CFU/mL cells or spores from different sporulation media and then incubated at 37°C for 336h. The number of cells decreased significantly with increasing pomegranate juice concentration in the blend juices and storage time (papple juice after 336h. On the other hand, the cell growth was inhibited for a certain time, and then the numbers started to increase after 72 and 144h in 10% and 20% blend juices, respectively. After 336h, total population among spores produced on PDA, BATA, BAA and MEA indicated 1.49, 1.65, 1.67, and 1.28 log reductions in pomegranate juice; and 1.51, 1.38, 1.40 and 1.16 log reductions in 80% blend juice, respectively. The inhibitory effects of 10%, 20% and 40% blend juices varied depending on the sporulation media used. The results obtained in this study suggested that pomegranate and pomegranate-apple blend juices could inhibit the growth of A. acidoterrestris DSM 3922 vegetative cells and spores. PMID:25676243
Molva, Celenk; Baysal, Ayse Handan
Sediment, a leading cause of water quality impairment, damages aquatic ecosystems and interferes with recreational uses and water treatment processes. A significant sediment source to streams, streambank retreat, has largely been ignored. Vegetation is an important component of stream restoration designs used to control streambank retreat, but vegetation effects on near bank flows need to be quantified. The goal of this research is to evaluate the effects of streambank vegetation on near bank flows and boundary shear stress. A flume experiment was conducted comparing three distinct streambank vegetation types: trees, shrubs, and grass. A second order prototype stream (Tom's Creek in Blacksburg, VA), with individual reaches dominated by the vegetation treatments was modeled using a fixed-bed Froude-scale modeling technique. One model streambank of the prototype stream was constructed for each vegetation type and compared to a bare control (only grain roughness). Simulated vegetation (e.g. woven grass mat and wooden dowels) was attached in locations identified in a field survey. Velocity profiles perpendicular to the flume model boundary will be evaluated along five cross sections for each vegetation treatment. Reynolds, law of the wall, and turbulent kinetic energy shear stresses will be analyzed using velocity measurements made with a three-dimensional acoustic Doppler velocimeter (ADV). Velocity profiles perpendicular to the flume model streambank will also be evaluated. The velocity profiles will be compared among vegetation types to see if profiles are similar along the bank face. This research is intended to improve our understanding of the role of riparian vegetation in stream morphology by evaluating the effects of vegetation on boundary shear stress, providing insight to the type and density of vegetation required for streambank stability. The results will also aide in quantifying sediment inputs from streambanks, providing quantitative information for stream restoration projects and watershed management planning.
Hopkinson, L. C.; Wynn, T. M.
The territory of Serbia and adjacent areas is built up by many geological formations of diverse composition/age belonging to a few major geostructural units. Some of them may contain enrichments of radioactive elements may be risks (as sources of radioactivity) to the health of population. By the airborne gamma-spectrometric surveys, applied at a few localities in diverse geological units, zones of geochemically anomalous radio-activity were discovered, related to different geological-geochemical systems. The anomalies, defined by gamma-ray radioactivity, a total and specific ones (of K-40, and Bi-214 and Tl-208, as indicators of U and Th, respectively), differ in both geochemical types and environmental-health impacts. (author)
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...
Abdelghani Chehbouni; Claire Gruhier; Zohra Lili-Chabaane; Mehrez Zribi; Rim Amri; Benoit Duchemin
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
Full Text Available This paper, the first in a series provides the background of the project, reports on the early phases of construction with the descriptions of the pre and post flooded conditions related to vegetation and land cover types surrounding the reservoir. Currently there are plans to develop the so called “Lower Churchill Area” by establishing new power plants at Gull Island and at Muskrat Falls with associated reservoirs. These new plants would use the discharged water of the plant from Churchill Falls and the additional water collected from some of the Churchill River Basin. The information provided by these papers could have relevance to the environmental evaluation of these new developments. The Churchill Falls Hydro Project (called the “Upper Churchill Development” in Labrador, Canada, was initiated in the late 1960s and the 5428-MW hydro generating plant constructed was then among the largest in the world. At that time, in general, not much attention was paid to the impact of such development on the flooding of vegetation especially forest stands. Both forested and un-forested terrestrial vegetation types were flooded (244 915 ha. Some islands were created and in addition portions of existing areas were flooded to form islands (74 075 ha in the Main (Smallwood Reservoir area. The flooded area of forest and un-forested land in the reservoir is 77% while the islands is 23 percent. The percentages of forested and un-forested areas lost to flooding are 64% and 36% respectively. The percent of commercial forests lost to flooding is approximately 1% and the non-commerci- al forests is 99% (with a total volume of approximately 10 million cubic meters of wood.
Bruce A. Roberts
Altered disturbance regimes in the context of global change are likely to have profound consequences for ecosystems. Interactions between fire and vegetation are of particular interest, as fire is a major driver of vegetation change, and vegetation properties (e.g., amount, flammability) alter fire regimes. Mediterranean-type ecosystems (MTEs) constitute a paradigmatic example of temperate fire-prone vegetation. Although these ecosystems may be heavily impacted by global change, disturbance regime shifts and the implications of fire-vegetation feedbacks in the dynamics of such biomes are still poorly characterized. We developed a minimal modeling framework incorporating key aspects of fire ecology and successional processes to evaluate the relative influence of extrinsic and intrinsic factors on disturbance and vegetation dynamics in systems composed of grassland, shrubland, and woodland mosaics, which characterize many MTEs. In this theoretical investigation, we performed extensive simulations representing different background rates of vegetation succession and disturbance regime (fire frequency and severity) processes that reflect a broad range of MTE environmental conditions. Varying fire-vegetation feedbacks can lead to different critical points in underlying processes of disturbance and sudden shifts in the vegetation state of grassland–shrubland–woodland systems, despite gradual changes in ecosystem drivers as defined by the environment. Vegetation flammability and disturbance stochasticity effectively modify system behavior, determining its heterogeneity and the existence of alternative stable states in MTEs. Small variations in system flammability and fire recurrence induced by climate or vegetation changes may trigger sudden shifts in the state of such ecosystems. The existence of threshold dynamics, alternative stable states, and contrasting system responses to environmental change has broad implications for MTE management.
Batllori, Enric; Ackerly, David D.; Moritz, Max A.
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
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.
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
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
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
Cuantificación del carbono almacenado en formaciones vegetales amazónicas en "CICRA", Madre de Dios (Perú) / Quantification of the carbon storage in amazon vegetation types at "CICRA", Madre de Dios (Peru)
Full Text Available SciELO Peru | Language: Spanish Abstract in spanish La llanura amazónica peruana se caracteriza por la presencia de múltiples formaciones vegetales. Éstas cada vez reciben mayor impacto por actividades antropogénicas tales como la minería y tala. Todo esto, sumado al cambio climático global, genera desconcierto sobre el futuro de los bosques. La iden [...] tificación de los niveles de almacenamiento de carbono en áreas boscosas, y específicamente en cada formación vegetal, permitiría un mejor manejo de las zonas de conservación, así como identificar las áreas potenciales que servirían para el financiamiento de la absorción de carbono y otros servicios ambientales. El presente estudio fue desarrollado en la estación Biológica del Centro de Investigación y Capacitación Río Los Amigos (CICRA). En el CICRA se identificaron tres formaciones vegetales principales, el bosque de terraza, el bosque inundable y el aguajal. Siendo los bosques de terraza los de mayor extensión y mayor cantidad de carbono acumulado. Como resultado se valorizó la vegetación presente en el CICRA, en alrededor de 11 millones de dólares americanos. El ingreso a la oferta de los bonos de carbono promovería la conservación de los bosques. Abstract in english The Peruvian Amazon Basin is characterized by the presence of multiple vegetation types. They are being given great impact by human activities such as mining and, logging. All this, coupled with global climate change, creates confusion about the future of our forests. The identification of levels of [...] carbon storage in forested areas, and specifically in each vegetation type, would allow better management of conservation areas, and then identify potential areas that could serve to finance carbon sequestration and other environmental services. This study was conducted at the Biological Station for Research and Training Center Rio Los Amigos (CICRA, Spanish acronym). At the station three main formations were identified, alluvial terrace forests, flood terrace forests and Mauritia swamps. The alluvial terrace forest presents the most extensive area and the highest amount of carbon stored. As result, CICRA vegetations were valued at approx. 11 millions U.S. dollars. Admission to the supply of carbon credits could promote Amazon forest conservation.
Carlos, Martel; Lianka, Cairampoma.
Constantly decreasing primary energy sources and environmental issues are part of the reason to seek alternatives by developing new technologies. Biomass as organic matter of vegetable origin and animals can be recycled, processed and used for the extraction of energy. In the presented work looking at the different types of biomass as a potential source for energy. A rating of the energy potential of different types of biomass. Furthermore, an overview of the main methods for processing and to generate energy. The final result of the work is a classification of different types of biomass and grouping in terms of their efficient processing to produce energy on a particular method. Key words: biomass energy, bioenergy, potential, ecology, bio-product, processing, gasification, pyrolysis, fermentation., burning
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
A crop masking technique based on Ashburn's vegetative index (AVI) was used to evaluate native vegetation as an indicator of crop moisture condition. A mask of the range areas (native vegetation) was generated for each of thirteen Great Plains LANDSAT MSS sample segments. These masks were compared to the digitized ground truth and accuracies were computed. An analysis of the types of errors indicates a consistency in errors among the segments. The mask represents a simple quick-look technique for evaluating vegetative cover.
Kinsler, M. C.
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
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.
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
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 c [...] om a participação de três coletores. O esforço de amostragem foi de 240 amostras, sendo 96 através de guarda-chuva entomológico e rede de varredura, 96 através de coleta manual noturna e 48 por triagem manual e extratores de Winkler. Foi comparada a diversidade de aranhas de quatro tipos de vegetação, Floresta Ombrófila Aberta, mata de galeria, áreas de Cerrado (Savana Arbórea) e de Campina. As coletas resultaram em um total de 4.990 indivíduos, dos quais 2.750 adultos. Foram identificadas 427 morfoespécies em 37 famílias, sendo as mais abundantes Theridiidae, Salticidae e Araneidae e as mais ricas em espécies Araneidae, Salticidae e Theridiidae. As espécies representadas por apenas um indivíduo somaram 40% do total e apenas duas ultrapassaram cem indivíduos. A curva de riqueza específica estimada (ACE) atingiu 614 espécies. A maior diversidade alfa (índice de Shannon-Wiener) foi encontrada em Floresta Ombrófila, seguida pela mata de galeria, Campina e Cerrado. Tais diferenças entre as vegetações podem ser explicadas devido a variações na complexidade da vegetação e na disponibilidade de microhábitats em cada fitofisionomia. Abstract in english An inventory of the spider fauna was carried out at Serra do Cachimbo, inside the "Campo de Provas Brigadeiro Velloso", municipality of Novo Progresso, state of Pará, Brazil. Two expeditions were made, during both dry (August and September, 2003) and wet (March and April, 2004) seasons. Three collec [...] tors participated in each expedition. The sampling effort, represented by 240 samples, was divided into the following methods: beating tray and sweeping net (96 samples); nocturnal hand search (96 samples) and concentrated litter sorted by a combination of hand search and Winkler extractors (48 samples). The spiders assemblages from four vegetation types (open rainforest, riparian forest, arboreal savanna and white sand vegetation) were compared. A total of 4,990 spiders were obtained, from which 2,750 adults, resulting in 427 morphospecies of 37 families. The most abundant families were Theridiidae, Salticidae, and Araneidae and the ones with more species were Salticidae, Araneidae, and Theridiidae. Singletons represented 40% of the total species richness and only two species presented more than 100 individuals. The estimated species richness curve produced by ACE reached 614 species. The highest alpha-diversity (Shannon-Wiener index) was observed in open rainforest, followed by riparian forest, white sand vegetation and arboreal savanna. These differences among the various vegetations can be explained by variations in vegetation complexity and micro-habitat availability in each vegetation type.
Janael, Ricetti; Alexandre B., Bonaldo.
Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model's predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model's predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model's performance is satisfactory when applied to the three selected vegetation types.
Duguy, Beatriz; Alloza, José Antonio; Baeza, M. Jaime; De la Riva, Juan; Echeverría, Maite; Ibarra, Paloma; Llovet, Juan; Cabello, Fernando Pérez; Rovira, Pere; Vallejo, Ramon V.
Operant performance of non-food deprived rats (n=8) was assessed under progressive ratio (PR) and concurrent PR-fixed ratio schedules of food pellet and/or vegetable shortening reinforcement. Post operant baselines, rats were matched and divided into 2 groups based upon the schedule of shortening availability: High restriction binge group (H, 1-hr home cage shortening access each week on Monday, Wednesday, and Friday) and Low restriction (L, 1-hr shortening access daily). Chow and water were continuously available; only access to the shortening was restricted. After 8 weeks, operant performance was reassessed. Lever pressing for shortening increased in the H rats for all schedules, but was either unaffected or decreased in the L rats. Pellet responding under the concurrent schedules increased for both groups. The effects of four dosages of (R)-baclofen (0.3-1.8 mg/kg, i.p.) on operant performance were also assessed. For both groups, 1.0 mg/kg baclofen significantly reduced shortening responding relative to saline for all schedules except one, but had no or minimal effect on pellet responding. This suggests a specific effect of baclofen on responding maintained by fat. These results indicate that intermittent episodes of bingeing on fat can increase the reinforcing efficacy of fat and that GABAB receptor activation can attenuate this effect. PMID:16782181
Wojnicki, F H E; Roberts, D C S; Corwin, R L W
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
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.
Viviane Gianluppi, Ferro; José Augusto, Teston.
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
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
A landslide inventory map was created for Horseshoe Run watershed, West Virginia, using high-resolution topographic data obtained from airborne LiDAR. A total of 152 landslides were remotely mapped and classified as planar slides, rotational slumps, debris flows, debris fans, debris slides, and active slopes based on morphologic characteristics interpreted from LiDAR-derived shaded relief maps, with field verification at several locations. Seven landscape variables were calculated for the watershed from the high-resolution (0.5-m) topographic data: elevation, slope angle, slope aspect, distance from roads, distance from streams, plan curvature, and profile curvature. Statistical analyses were conducted to determine the mean and standard deviations for each variable and corresponding slope failure type. Discriminant analyses were conducted on the different types of failed slopes, with a maximum 86% accuracy level, to determine which landscape characteristics contribute to each type of landslide. Results from the discriminant analyses indicate that statistically significant differences exist between the failure classes mapped within the watershed and that slope angle, slope aspect, and landscape curvature are important variables influencing the type of process. The results from this study have important implications for predicting where certain types of slope failures may occur based on landscape characteristics.
Konsoer, Kory M.; Kite, J. Steven
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.)
A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and ...
Mcmahon, Kathryn; Dijk, Kor-jent; Ruiz-montoya, Leonardo; Kendrick, Gary A.; Krauss, Siegfried L.; Waycott, Michelle; Verduin, Jennifer; Lowe, Ryan; Statton, John; Brown, Eloise; Duarte, Carlos
Caracterização fitofisionômica e levantamento florístico preliminar no Pantanal dos Rios Mortes-Araguaia, Cocalinho, Mato Grosso, Brasil / Vegetation types and preliminary floristic survey in the Mortes-Araguaia Pantanal, Cocalinho, Mato Grosso, Brazil
Full Text Available O presente estudo realizou-se no Pantanal dos Rios Mortes-Araguaia, extensa planície inundável localizada no municípo de Cocalinho, nordeste de Mato Grosso, Brasil. Efetuou-se uma caracterização fitofisionômica e um levantamento florístico preliminar da região. Foram selecionados três Sítios, com fi [...] tofisionomias representativas: proximidades do Rio das Mortes (12° 37'S; 50° 55'W), foz do Rio das Mortes com o Araguaia (11° 54'S; 50° 48'W) e porção mediana do Rio Cristalino (12° 52'S; 50° 49'W). O método de amostragem adotado foi o de levantamentos rápidos. Foram identificadas oito fitofisionomias: Mata Inundável, Caapão, Babaçual, Cerradão, Cerrado stricto sensu, Campo de Murunduns, Campo de Byrsonima orbignyana e Campo Cerrado de Vochysia rufa. Foram levantadas 248 espécies de árvores, arbustos, sub-arbustos e lianas, distribuídas em 158 gêneros e 62 famílias. As fitofisionomias apresentaram um padrão heterogêneo, sendo que nenhuma das espécies ocorreu em todas elas. Porém, Alibertia edulis (L. Rich.) A. Rich., Andira cuyabensis Benth., Maprounea guianensis (Aubl.) M. Arg., entre outras, ocorreram em seis das oito fitofisionomias. As famílias com maior riqueza foram: Caesalpiniaceae, Annonaceae e Myrtaceae. Ocorreram algumas semelhanças florísticas com o Pantanal do Rio Paraguai, porém, são necessários estudos mais aprofundados para confirmar. Os padrões de heterogeneidade fitofisionômica indicam que a área estudada necessita de medidas conservacionistas. Abstract in english This study was carried out in the Pantanal of the Mortes and Araguaia rivers, a flooded plain located in Cocalinho, northeastern Mato Grosso, Brazil. The objectives of this study were to conduct a preliminary survey of the flora and to characterize the vegetation types. Three representative sites we [...] re selected: one near Rio das Mortes (12° 37'S; 50° 55'W), one at the mouth of Araguaia and Mortes rivers (11° 54'S; 50° 48'W) and one in the middle portion of the Cristalino river (12° 52'S; 50° 49'W). Sampling was by the Rapid Survey method. Eight vegetation types were identified: Mata Inundável (swamp forest), Caapão (also swamp forest), Babaçual (Attalea speciosa forest), Cerradão, Cerrado stricto sensu (savanna types, closed canopy woodland and savanna grassland, respectively), Campo de Murunduns (grassland with scattered mounds bearing termites), Campo de Byrsonima orbignyana (grassland dominated by B. orbignyana) and Campo Cerrado de Vochysia rufa (grassland with scattered trees of V. rufa). A total of 248 species of trees, shrubs and lianas were recorded, distributed in 158 genera and 62 families. The vegetation types were heterogeneous; none of the species occurred at all sites, but Alibertia edulis (L. Rich.) A. Rich., Andira cuyabensis Benth., Maprounea guianensis (Aubl.) M. Arg., and others, were found at six sites. The families richest in species were Caesalpiniaceae, Annonaceae and Myrtaceae. The flora apparently was similar to that of the Pantanal of Paraguai river, however, further studies are needed to confirm. This Heterogeneous vegetation patterns in the study area indicate the need to protect the Pantanal of the Mortes and Araguaia rivers.
Beatriz Schwantes, Marimon; Edson de Souza, Lima.
This detailed resource is provided by the California Native Plant Society (CNPS), an organization of amateurs and professionals "united by an interest in the plants of California." In a move towards landscape-based management and away from single-species management, the vegetation classification system and manual is organized here by "series": herbs, shrubs, trees, unique stands (cypress stands, all-thorn stands), habitat types (fens, alpine), and vernal pools (basalt, claypan, etc.). The site provides series keys to assist users in determining the appropriate classification for an area. Details within each series include habitat-based information, associations, canopy cover, ground layer, elevation, and references. In addition, each series page features links to Common species and geographical associated regions, which point users to related tables, graphics, or entire Websites.
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
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.
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
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
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.
Full Text Available Platberg is an inselberg that presents a refuge for indigenous plants and animals. Uncontrolled human access to this area threatens this sensitive ecosystem. The vegetation of Platberg was investigated to obtain an inventory of the different plant species and communities present in this area. A hierarchical classification, a description and an ecological interpretation of the grassland communities of Platberg are presented. A total of 169 sample plots were placed on a stratified random basis within the study area. From a TWINSPAN classification a total of 27 different plant communities, which can be grouped into two major community types, nine communities, 18 sub-communities and six variants, were identified. A significant difference in species richness was found between the two major communities, with the higher-altitude communities having a higher species richness than the communities on the lower-lying slopes. A total of 26 endemic or near endemic Drakensberg Alpine Centre species were recorded.
Conservation implications: Anthropogenic influences are felt globally on ecosystems. High-altitude habitats and organisms will be affected first. Inselbergs have high levels of endemic organisms and are reservoirs and refugia for unique genetic material. This grassland plant community survey of Platberg provides valuable information on inselberg ecology for conservation planning.
How to cite this article: Brand, R.F., Brown, L.R. & Du Preez, P.J., 2011, ‘The Grassland vegetation of Platberg, eastern Free State, South Africa’, Koedoe 53(1, Art. #1027, 13 pages. http://dx.doi.org/10.4102/koedoe.v53i1.1027
Robert F. Brand
Full Text Available SciELO South Africa | Language: English Abstract in english Platberg is an inselberg that presents a refuge for indigenous plants and animals. Uncontrolled human access to this area threatens this sensitive ecosystem. The vegetation of Platberg was investigated to obtain an inventory of the different plant species and communities present in this area. A hier [...] archical classification, a description and an ecological interpretation of the grassland communities of Platberg are presented. A total of 169 sample plots were placed on a stratified random basis within the study area. From a TWINSPAN classification a total of 27 different plant communities, which can be grouped into two major community types, nine communities, 18 sub-communities and six variants, were identified. A significant difference in species richness was found between the two major communities, with the higher-altitude communities having a higher species richness than the communities on the lower-lying slopes. A total of 26 endemic or near endemic Drakensberg Alpine Centre species were recorded. CONSERVATION IMPLICATIONS: Anthropogenic influences are felt globally on ecosystems. Highaltitude habitats and organisms will be affected first. Inselbergs have high levels of endemic organisms and are reservoirs and refugia for unique genetic material. This grassland plant community survey of Platberg provides valuable information on inselberg ecology for conservation planning.
Robert F., Brand; Leslie R., Brown; Pieter J., du Preez.
Correlações fenotípicas entre tamanho de grãos e outros caracteres em topocruzamentos de soja tipo alimento com tipo grão / Phenotypic correlation between seed size and other characteristics in topcrosses of vegetable soybean with grain type
Full Text Available Este trabalho foi conduzido para avaliar a correlação fenotípica entre vários caracteres em topocruzamentos entre soja tipo alimento e soja tipo grão (Doko e FT-2). Valores de interesse para facilitar a seleção foram obtidos nas correlações entre peso de cem sementes (tamanho de sementes) e dias par [...] a atingir a maturidade, e entre tamanho de sementes e largura visual da vagem. Na correlação entre produtividade de grãos e tamanho de sementes somente os topocruzamentos com Doko foram significativos. As estimativas de correlações em plantas individuais tenderam a confirmar aquelas obtidas em médias de parcelas. Os valores de correlação foram diferentes entre os tipos (grão, broto/"natto" e hortaliça) de soja envolvidos, o que sugere a adoção de estratégias de seleção distintas. O estudo de correlações para cada topocruzamento é importante, pois podem ocorrer diferenças no desempenho das plantas como foi observado nos resultados obtidos. Abstract in english This work was conducted to evaluate the phenotypic correlation between characters in topcrosses between vegetable soybean with grain type cultivars (Doko and FT-2). Interesting values to facilitate selections were observed in correlations between one hundred seed weight (seed size) and days of matur [...] ation and between seed size and pod width as visual score. Seed yield and seed size were significantly correlated only in Doko's topcrosses. Estimated correlation from individual plants tended to confirm those obtained at mean level plot. Depending on the soybean type (grain, sprout/natto and vegetable), the correlation values were different. Because of that it is recommended different selection strategies to evaluate distinct soybean classes. Correlation studies for each topcross are important, due to differences in plant performance as observed in obtained results.
GILBERTO KEN-ITI, YOKOMIZO; JOÃO BATISTA, DUARTE; NATAL ANTONIO, VELLO.
Based on Digital Elevation Models (DEM) and satellite SPOT-5 data, and by using the spatial analysis function in Geographic Information System, a hierachical Ecological Classification System of forest landscape was developed for the eastern mountainous region of Liaoning Province, and the two lowest layers in the hierachical framework, Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs), were mapped. The results indicated that there were 5 ELTs and 34 ELTPs. The boundaries of ELTs, which presented the potential vegetation distribution and potential forestry ecosystem productivity, were determined by environmental conditions quantified by DEM. ELTPs were classified by overlaying ELTs with forest vegetation data layers which were obtained from remotely sensed data, forest inventory data, and ground data. The ELTPs represented the divisions of land in terms of both natural and human-induced forest conditions, and therefore, were reliable units for forest inventories and management. ELTPs could function as conventional forest inventory sub-compartments. By this means, forestry departments could adjust forest management planning and forest management measures from the viewpoint of forest landscape scale to realize forest ecosystem management. PMID:18419066
Tang, Li-na; Wang, Qing-li; Dai, Li-min; Shao, Guo-fan
Full Text Available A floodplain-restoration project along the Danube between Neuburg and Ingolstadt (Germany aims to bring back water and sediment dynamic to the floodplain. The accompanied long-term monitoring has to document the changes in biodiversity related to this new dynamics. Considerations on and results of the vegetation monitoring concept are documented in this paper. In a habitat rich ecosystem like a floodplain different habitats (alluvial forest, semi-aquatic/aquatic sites have different demands on the sampling methods. Therefore, different monitoring designs (preferential, random, systematic, stratified random and transect sampling are discussed and tested for their use in different habitat types of the floodplain. A stratified random sampling is chosen for the alluvial forest stands, as it guarantees an equal distribution of the monitoring plots along the main driving factors, i.e. influence of water. The parameters distance to barrage, ecological flooding, height above thalweg and distance to the new floodplain river are used for stratifying and the plots are placed randomly into these strata, resulting in 117 permanent plots. Due to small changes at the semi-aquatic/aquatic sites a transect sampling was chosen. Further, a rough stratification (channel bed, river bank adjacent floodplain was implemented, which was only possible after the start of the restoration project. To capture the small-scale changes due to the restoration measures on the vegetation, 99 additional plots completed the transect sampling. We conclude that hetereogenous study areas need different monitoring approaches, but, later on, a joint analysis must be possible
Cells and spores of 40 strains of C1. perfringens type A, pathogenic for guinea pigs, were tested for resistance to antibiotics, drugs, disinfectants used in surgery and in bacteriological laboratories, and UV light. No correlation was found between thermoresistance of spores and their resistance to other bactericidal agents. Among the common disinfectants, iodine solution showed strong bactericidal and sporostatic activity. Good bactericidal effect was also obtained by combined action of Vescodin and UV light. Drug resistance of C1. perfringens type A strains changed clearly in the past 10 years. Strains inducing gangrene became resistant to penicillin and tetracyclines, which hitherto were commonly applied. Ampicilin can now be recommended, as the antibiotic with strong bactericidal and sporostatic action. (author)
Based on the field survey of swamp ecological characteristics and environmental quality and the ecological investigation of drained swamp transects in Zoige Plateau of Tibet in 2009, twenty typical swamp plots in the Plateau were classified into three types by TWINSPAN, i. e., primary swamp, long-term drained degraded swamp, and short-term drained degraded swamp, and each type of the degraded swamps was divided into three degradation grades, i. e., light degradation, moderate degradation, and severe degradation, with the degradation characteristics of vegetation and soil along the swamp degraded gradient studied. The swamp degradation in the Plateau was mainly driven by drainage pattern, drainage intensity, and soil moisture gradient, and the vegetation degradation was more obvious than the soil degradation. In the vegetation degradation, the structural change of hydro-type functional assemblage was most obvious, e. g., the importance value of helophytes under the stress of long-term drainage and short-term drainage decreased from 0.920 to 0.183 and 0.053, while that of mesophytes increased from 0.029 to 0.613 and 0.686, respectively. The soil response to the swamp degradation was in hysteresis, i. e., the soil physical and chemical properties presented definite variations but the differences were not significant among the swamps with different grades of degradation. The results of CCA indicated that soil moisture and nitrogen and potassium contents were the most important factors affecting the plant species distribution in drained degraded swamps in Zoige Plateau. PMID:23173449
Li, Ke; Yang, Yong-Xing; Yang, Yang; Han, Da-Yong
We present preliminary results from a set of recent experiments conducted in the Total Environment Simulator flume at the University of Hull in the framework of the Hydralab IV EU project. The aim of these experiments is to identify and assess the effects of riparian vegetation and large wood on the morphodynamics of braided river channels. The type and size of riparian vegetation is known to play a crucial role in shaping rivers, acting as a proper riparian engineer. Riparian vegetation influences bank stability, increases mean channel depth and can affect planform pattern by reducing the number of active branches. However, the geomorphic effect of plants can continue well after their erosion from banks. As dead or living pieces of large wood are transported through the fluvial network, they can exert a tremendous influence on river erosion and sedimentation processes, channel morphology, channel hydraulics, and ecological diversity of river channels. Our experiments consisted of different scenarios of presence / absence of riparian vegetation (simulated using alfalfa sprouts) and large wood density (simulated using wooden dowels). The experiments were designed to assess both the individual effects of woody debris and bank vegetation, as well as their combined effects. Each experiment has been characterised in terms of planform configuration (the number of active branches per cross-section) and bed topography (surveyed by a terrestrial laser scanner). Detailed DEM differencing was used to investigate sediment transport patterns and dynamics for the different vegetation-wood scenarios. The results of this work will help improve the ability to predict the response of river systems to different disturbances and management strategies.
Mao, L.; Bertoldi, W.; Comiti, F.; Gurnell, A. M.; McLelland, S. J.; Osei, N.; Ravazzolo, D.; Tal, M.; Welber, M.; Zanella, S.
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
We analyzed trends in time series of the normalized difference vegetation index (NDVI) from multitemporal satellite imagery for 2001-2010 over the southeastern Everglades where major changes in vegetation structure and type have been associated with sea-level rise and reduced freshwater flow since the 1940s. Non-parametric trend analysis using the Theil-Sen slope revealed that 84.4% of statistically significant trends in NDVI were negative, mainly concentrated in scrub mangrove, sawgrass (Cladium jamaicense) and spike rush (Eleocharis cellulosa) communities within 5 km of the shoreline. Observed trends were consistent with trends in sawgrass biomass measurements made from 1999-2010 in three Long-term Ecological Research (LTER) sites within our study area. A map of significant trends overlaid on a RapidEye high-resolution satellite image showed large patches of negative trends parallel to the shoreline in and around the 'white zone,' which corresponds to a low-productivity band that has moved inland over the past 70 years. Significantly positive trends were observed mainly in the halophytic prairie community where highly salt tolerant species are typically found. Taken as a whole, the results suggest that increased saline intrusion associated with sea-level rise continues to reduce the photosynthetic biomass within freshwater and oligohaline marsh communities of the southeastern Everglades. Trends in 2001-2010 NDVI in southern saline Everglades wetlands of South Florida. a) slope values; b) areas of significant slope; c) location of the study area.
Fuller, D. O.
In this contribution we have summarized the results of research a season dynamic of vegetation which was realized in the locality of the Bab forest (village Velky Bab, Nitra loess upland) in the vegetative period of 2013. The Bab forest is a lowland oak-hornbeam forest in an intensively exploited agricultural country. This forest is the remnant of formerly larger indigenous forest complexes. The Bab forest represents a type of indigenous vegetation in this area. Specifically, this contribution is focused on the evaluation and comparison season dynamic of vegetation on two types of outposts - clear-cuts and forest vegetation. (author)
Background In savannah-dominated Bénin, West Africa, and forest-dominated Gabon, Central Africa, plants are a major source of healthcare for women and children. Due to this high demand and the reliance on wild populations as sources for medicinal plants, overharvesting of African medicinal plants is a common concern. Few studies in Western Africa, however, have assessed variations in harvest patterns across different ecological zones and within local communities. Methods We investigated which vegetation types women accessed to harvest medicinal plants by conducting 163 questionnaires with market vendors and women from urban and rural communities. We made botanical vouchers of cited species and collected information on their vegetation type and cultivation status. Results Secondary vegetation was a crucial asset; over 80% of the 335 Beninese and 272 Gabonese plant species came from disturbance vegetation and home gardens. In Bénin, access to trade channels allowed female market vendors to use more vulnerable species than rural and urban women who harvested for personal use. In Gabon, no relationship was found between vulnerable plant use and informant type. Conclusions This study highlights the underemphasized point that secondary vegetation is an asset for women and children’s health in both savanna-dominated and forest-dominated landscapes. The use of disturbance vegetation demonstrates women’s resilience in meeting healthcare needs in the limited amount of space that is available to them. Species of conservation concern included forest species and savanna trees sold at markets in Bénin, especially Xylopia aethiopica, Khaya senegalensis, and Monodora myristica, and the timber trees with medicinal values in Gabon, such as Baillonella toxisperma. PMID:24885805
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.
Full Text Available A propagação vegetativa é considerada importante ferramenta para o melhoramento de espécies lenhosas e herbáceas e vem sendo amplamente utilizada, visando melhorar e manter variedades de importância econômica e medicinal. Neste contexto utilizou-se estacas de alfavaca-cravo de 15 cm para apicais e 25 cm para as medianas, sendo estas com e sem folhas. As estacas foram plantadas em bandejas de isopor de 72 células, utilizando-se 10 substratos. Após 35 dias, as estacas foram retiradas com cuidado, sendo as partes aéreas e radiculares separadas e acondicionadas em saco de papel e mantidas em estufa a 70ºC por 48 h para posterior avaliação da matéria seca. Analisou-se a percentagem de enraizamento, número de folhas na estaca, peso de matéria seca de folha e de raiz. Não houve interação significativa entre os diferentes tipos de substrato e estaca para percentagem de enraizamento, sendo que os substratos de modo geral diferiram pouco entre si. Entre os tipos de estaca destacaram-se para esta variável a mediana sem folha e a apical com folha. Para as demais variáveis houve interação significativa entre o tipo de estaca e o substrato. A melhor estaca foi a mediana sem folhas plantadas em substrato arisco + esterco + húmus e vermiculita nas seguintes proporções: 20%:40%:40%; 40%:20%:40% e 40%:40%.The vegetative propagation is an important tool for the improvement of woody and herbaceous species and could be an important tool to improve and to maintain varieties of economic and medicinal importance. In this experiment cuttings 15 cm long of the apical portion and also 25 cm long cuttings of the medial portion of the stems, were used both with and without leaves. The cuttings were planted on styrofoam trays with 72 cells, using 10 different substrata. After 35 days, cuttings were carefully removed, the aerial portion being separated from the roots and conditioned in paper bags and maintained in a stove at 70ºC for 48 h, for the dry weight evaluation. There were analyzed the percentage of rooting, number of leaves per cutting and leaf and root dry weight. There was no interaction among substrata and cuttings for the percentage of rooting. Were no significant differences in the rooting among the different substrata used in the experiment there. Better rooting was observed on cuttings from the medial portion of the stem without leaves and from the apical portion with leaves. For the other variables there was significant interaction between the cuttings and the substrata. The cutting that presented best results were those from the medial portion without leaves in the substrata with A+E sandy soil + humus + vermiculite in the following proportions: (20%: 40%:40%; (40%:20%:40% and (40%:40%:20% respectively.
Polyana Aparecida D. Ehlert
It constructs total system reduced as a compost in the farmland again the organic waste that resource recycling was made into taking dioxin problem as an opportunity in the up-date environmental preservation resources cycloid type society. We would require the possible material of the composting such situation, then agricultural material and garbage cutwater network and garbage collection bag such as used multi- film, food container and packaging material besides. We developed natural circulation highly functional product aggregate which was various taking the polylactic acid as main raw material on the basis of the our company original giant molecule forming technology. (NEDO)
Mochizuki, M. [Unitika Ltd., Osaka (Japan)
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
This book presents the proceedings of a workshop on community ecology organized at Davis, in April, 1986, sponsored by the Sloan Foundation. There have been several recent symposia on community ecology (Strong et. al., 1984, Diamond and Case, 1987) which have covered a wide range of topics. The goal of the workshop at Davis was more narrow: to explore the role of scale in developing a theoretical approach to understanding communities. There are a number of aspects of scale that enter into attempts to understand ecological communities. One of the most basic is organizational scale. Should community ecology proceed by building up from population biology? This question and its ramifications are stressed throughout the book and explored in the first chapter by Simon Levin. Notions of scale have long been important in understanding physical systems. Thus, in understanding the interactions of organisms with their physical environment, questions of scale become paramount. These more physical questions illustrate the...
This site describes phytoplankton ecology research by marine ecologists at Mote Marine Laboratory (MML), an independent, nonprofit research organization based in Sarasota, Florida. The emphasis of MML's phytoplankton ecology research is the photophysiology of marine algae -- with recent emphasis on the ability to predict and possibly mitigate blooms of the toxic marine dinoflagellate, Gymnodinium breve. The no-frills phytoplankton ecology homepage describes research and offers data (maps, figures, tables) from 1998 and 1999 projects on Red Tide transects, Nutrient and chlorophyll concentrations, and Ecology and Oceanography of Harmful Algal Blooms (ECOHAB) transect data, among several others. The site also offers general information on Red Tides, Red Tide conditions in Southwest Florida, a chronology of historic Red Tide events, and links to related resources.
When people think about the concept and idea of ecology, they may not immediately picture a bustling urban street or a network of interconnected bike paths. Since 1975, a group of architects and activists have been thinking about exactly those things in terms of urban ecology (and a good deal more to boot), coupling it with a conviction that urban ecology can draw on ecology, public participation and urban planning "to help design and build healthier cities." Given these ideas, it seems logical that this organization has its roots in the Bay Area, and continues to offer up interesting plans and proposals, many of which can be found on the website. One such document is the Walkable Streets Toolkit, which is designed for use by communities that seek to make their streets more pedestrian friendly. Additionally, visitors will want to look at current and past editions of The Urban Ecologist, which is the group's quarterly newsletter.
Since fire has been recognized as an essential disturbance in Mediterranean landscapes, the study of long-term fire ecology has developed rapidly. We have reconstructed a sequence of vegetation dynamics and fire changes across south-eastern Iberia by coupling records of climate, fire, vegetation and human activities. We calculated fire activity anomalies (FAAs) in relation to 3 ka cal BP for 10-8 ka cal BP, 6 ka cal BP, 4 ka cal BP and the present. For most of the Early to the Mid-Holocene uneven, but low fire events were the main vegetation driver at high altitudes where broadleaved and coniferous trees presented a highly dynamic post-fire response. At mid-altitudes in the mainland Segura Mountains, fire activity remained relatively stable, at similar levels to recent times. We hypothesize that coastal areas, both mountains and lowlands, were more fire-prone landscapes as biomass was more likely to have accumulated than in the inland regions, triggering regular fire events. The wet and warm phase towards the Mid-Holocene (between ca 8 and 6 ka cal BP) affected the whole region and promoted the spread of mesophytic forest co-existing with Pinus, as FAAs appear strongly negative at 6 ka cal BP, with a less important role of fire. Mid and Late Holocene landscapes were shaped by an increasing aridity trend and the rise of human occupation, especially in the coastal mountains where forest disappeared from ca 2 ka cal BP. Mediterranean-type vegetation (evergreen oaks and Pinus pinaster- halepensis types) showed the fastest post-fire vegetation dynamics over time.
Gil-Romera, Graciela; Carrión, José S.; Pausas, Juli G.; Sevilla-Callejo, Miguel; Lamb, Henry F.; Fernández, Santiago; Burjachs, Francesc
This website from the National Wildlife Federation showcases environmental conservation projects that have been successfully undertaken by various universities. The site features example projects and resources for doing your own campus project. Topics include building design, energy, environmental literacy, habitat restoration, water, transportation and waste reduction. Links to the online Campus Ecology Yearbook and the Campus Ecology Research Station and other resources are also included.
National Wildlife Federation
The attitudes and behaviours of private landholders toward the conservation of a highly transformed and critically endangered habitat, Overberg Coastal Renosterveld (OCR) (a grassy shrubland of the Cape Floral Region, South Africa) are described. Personal, semistructured interviews were conducted with landholders, representing 40 properties in the Overberg region, on topics such as management and utilisation of OCR, the depth of their knowledge of its conservation importance, what they perceive its value to be, and the extent of their willingness to conserve it. General attitudes toward conservation incentives and provincial conservation authorities were also investigated. Farmers more willing to conserve were younger, did not necessarily have a better education, and owned larger farms (>500 ha) with a greater amount of remnant renosterveld (>300 ha) than those less willing to conserve. Attitudes toward the OCR were largely negative, related to associated problem plants and animals and the fact that it is believed not to be economically advantageous to retain it. However, farmers are of the opinion that provision of incentives and increased extension support will provide practical positive inducements for conservation. Landholder education is paramount to prevent further transformation of critically endangered habitats. The success of private-conservation programs depends on the attitudes of landowners toward (1) the particular habitat or species to be conserved (which can vary depending on the type of land use practised and the associated benefits and disadvantages of that habitat type); (2) the conservation agency or extension officers responsible for that area; and (3) willingness of landowners to participate in a conservation program, which is influenced by landowner age, farm size, and the amount of natural habitat left to conserve.
Winter, Susan J.; Prozesky, Heidi; Esler, Karen J.
Abstract: Grazed coastal grassland in eastern Denmark - Managing plant communities to preserve rare plant species This study analyzes vegetation of coastal grassland in an embanked nature reserve (c. 2000 ha) south of Copenhagen on the island Amager. The focus is on grazing effects on abundance of Iris spuria, Selinum dubium and Cerastium subtetrandrum. The main objectives are to identify plant communities and site factors related to the target species. Considering the ecological requirements of the species it is possible to estimate their potential distribution in the study area. Based on these results, management on the rare plants is discussed. Vegetation data, consisting of 73 relevés collected in summer 2008, are classified using TWINSPAN analysis and ordination by DCA. Thus, the main vegetation units and underlying environmental gradients are identified and assigned to plant communities known from the literature. Recent vegetation changes are analysed by DCA using published data from 2004 and 2006. The main factors defining the grassland vegetation of Vestamager are salinity, moisture and grazing. Nutrientpoor, salt-affected and grazed communities of the Lolio-Cynosuretum are the most common vegetation type in the study area. This association can be divided into a subtype of moist grassland, including species of wetland meadows (Molinion), and drier grassland, with floristic affinities to Mesobromion. In the southwest of the study area, with slightly higher salinity, the Lolio-Cynosuretum is replaced by 243 Juncetum gerardii salt marshes. Within the salt marshes pioneer vegetation is developed on ant hills. The transition between geo- and hydrolitoral is colonized by brackish reeds. On intensely grazed, moist to wet sites the Lolio-Cynosuretum is replaced by the Ranunculo repentis-Alopecuretum geniculati. Tall grassland dominated by Calamagrostis epigejos develops under reduced grazing pressure. Iris spuria and Selinum dubium occur with one stand each in the north of the study area. Thepopulations are associated with drier parts of the Lolio-Cynosuretum juncetosum gerardii. Smaller populations of Selinum dubium are found in Plantago major communities. Cerastium subtetrandrum is represented with several small populations on ant hills in salt-pioneer marsh. Iris spuria is sensitive to grazing, and thus the intensification of grazing on Vestamager has resulted in a decreasing population of this species in the past years. Selinum dubium is more tolerant, and vegetative individuals are able to persist in grazed areas. Cerastium subtetrandrum depends indirectly on grazing. Potential habitats of this species are maintained by grazing. Intensification of grazing and shrub clearance have reduced cover of woody species and tall grasses promoting less competitive species. Recently, a development towards open saltinfluenced grassland can be observed, albeit without increasing floristic diversity. Optimal conservation of the target species seems only feasible if a more diverse management is applied. For conservation of Iris spuria and Selinum dubium a local reduction of grazing is recommended including exclosures. Preservation of Cerastium subtetrandrum, however, depends on low vegetation, which calls for relatively intense grazing. In the long term, higher diversity will only be achieved by spatio-temporal variation of grazing intensity which would also accommodate the different demands of the target species. Keywords: Cerastium subtetrandrum, conservation management, grazing variation, Iris spuria, salt marsh, Selinum dubium, target species.
Heimes, Christine; Kollmann, Johannes Christian
In Central Europe freshwater ecosystems have to deal with a loss of habitat structures due to channelisation and standardisation. Unimpaired streams and rivers are very rare, which leads to a few, remaining populations of sensitive invertebrate species which are severely fragmented. This progress is mainly noticed in lowland rivers in agricultural intensely used areas, where habitat degradation and pollution affect the ecosystems. Additional pressures on the freshwater systems will be expected due to climate change effects. In the Austrian Lowlands, an increase of air temperature about 2-2.5 °C is predicted till 2040. This will in turn lead to the highest increase in water temperature in the lowland rivers of the "Hungarian Plains", Ecoregion 11 on which the impacts of climate change will most likely be highest in Austria. Global warming on its own may lead to severe changes in aquatic ecosystems. Human impacts increase the negative effects even more. Main factors for a sustainable survival of benthic invertebrates and fishes are closely connected with parameters like water temperature, the availability of oxygen and nutrients, or radiation and nutrients for primary production which are closely related to climate. Natural bank vegetation reduces the influx of solar radiation as well as it forms a microclimate of its own and could provide very important niches for terrestrial and aquatic stages. Riparian areas with trees provide direct shade for the water body and thus avoiding the corresponding increase in water temperature. Wide riparian wooded areas can even decrease evaporation and increase the relative air humidity, which contributes to reducing water temperature. Input of deadwood like trees or logs represents essential habitats for invertebrates and fish assemblages. Its presence is one essential drivers of bed-morphology creating heterogeneous instream habitat patterns. In the framework of the project BIO_CLIC the potential of riparian vegetation to mitigate effects of climate change on biological assemblages of small and medium sized running waters will be investigated. The results support river managers in implementing integrative guidelines for sustainable river restoration towards climate change adaptation, ecological services and socio-economic consequences. In this paper the influence of riparian vegetation on the energy input of rivers will be highlighted. As a first step in field works habitat characteristics will be examined and described. First results show riparian vegetation datasets for different riparian vegetation types with 3D spatial distribution of vegetation, riparian vegetation composition and radiation attenuation coefficients for different vegetation types.
Holzapfel, Gerda; Rauch, Hans Peter; Weihs, Philipp; Trimmel, Heidelinde; Formayer, Herbert; Leitner, Patrick; Graf, Wolfram; Melcher, Andreas; Dossi, Florian
After the Chernobyl accident, reindeer pastures in Fennoscandia were contaminated with radioactive material (mainly 137Cs). There were large geographical variations in contamination of reindeer and in apparent transfer of 137Cs from ground and vegetation to reindeer. There could be several reasons for the observed differences between areas. This work aims at collecting basic data on 137Cs activity concentrations in soil, vegetation and reindeer and constructing a model to describe the transfer of radiocaesium to reindeer over time. Field data on 137Cs in soil and vegetation has been collected during two years from one reindeer herding district (Jiingevaerie) in central Sweden. Data on 137Cs in reindeer is available from the same area from 1986 to 1998. The collected data, and data from earlier investigations, has been put in a simple dynamic model, taking into account ground deposition, initial transfer of 137Cs from fallout to different types of vegetation and long term change of 137Cs in vegetation as well as food intake, diet composition, absorption and biological half-time of 137Cs in reindeer. The ground contamination of 137Cs was 9 441 Bq/m2, at average, within reindeer pastures used during the summer period and 22 629 Bq/m2 within the areas used in wintertime. The relation between ground contamination and vegetation differed very much between and vegetation differed very much between sampling sites but were generally higher for lichens (however, not statistically significant) and fungi (significant). The relation between ground contamination and reindeer (Tag) counted back to 1986 with the observed effective ecological half-time (tef = 3. 6 years), was 0. 14 m2/kg for the season August-September and 0. 69 and 0. 66 m2/kg for the seasons October-December and January-April, respectively. Three simulations of 137Cs in reindeer over 12 years were made with the constructed model and simulated values were compared to observed activity concentrations of 137Cs in reindeer from 1986 to 1998. The simulated curves followed the same pattern as observed values but were slightly high for the summer period. Two simulations (a and c) gave low values for the winter period, while one simulation (b) did not differ significantly from values observed during the winter period. More data need to be collected, especially on relation between ground contamination and contamination of vegetation and long term change of 137Cs in vegetation, to get better input data for the model. The variation in diet, and factors that govern changes in diet, also need to be more thoroughly investigated
Predicciones de cambios en los principales tipos de vegetación de Chile bajo cambio climático basados en un estudio preliminar: Modelos, incertidumbres y adaptación de la investigación para un mundo de biodiversidad dinámica Changes in the main vegetation types of Chile predicted under climate change based on a preliminary study: Models, uncertainties and adapting research to a dynamic biodiversity world
Full Text Available Los efectos del cambio climático sobre la biodiversidad ocurren a diferentes niveles de organización (organismos, especies y ecosistemas. La vegetación se encuentra relacionada directamente con el clima, por lo que se espera que el calentamiento global altere la distribución de los tipos de vegetación para el futuro cercano. Usando un enfoque de envoltura bioclimática, los tipos de vegetación de Chile fueron modelados y proyectados usando escenarios del IPCC para el año 2080. Los resultados presentan diferentes transiciones entre los tipos de vegetación, en relación a su distribución latitudinal y altitudinal actual. Entre los cambios principales, se identifica el avance altitudinal de la vegetación alpina, la expansión hacia el sur del desierto absoluto y del matorral desértico sobre el bosque escleróflo. Se esperan cambios en la representación relativa de las áreas protegidas dentro de los diferentes tipos de vegetación de Chile. Las limitaciones del ejercicio de modelación son discutidas junto a la necesidad de mejorar el conocimiento científico sobre procesos biológicos claves como dispersión y polinización.Climate change effects on biodiversity occur at different level of organization (organisms, species and ecosystems. Vegetation type bears a close relationship with climate, such that global warming is ex-pected to alter the distribution of major vegetation types in the near future. Using a bioclimatic envelope modeling approach, the major vegetation types of Chile were modeled and projected using IPCC scenarios for year 2080. The results show transitions among vegetation types in relation to their current latitudinal and altitudinal distribution. Major changes include an upward shift of the alpine vegetation and southward expansion of absolute desert and desert scrub into the present area of sclerophyllous forest. Changes in the relative representation of different vegetation types in Chile´s protected areas can be expected. The limitations of modeling exercises are discussed along with need for better scientific knowledge on key biological processes such as dispersal and pollination.
Predicciones de cambios en los principales tipos de vegetación de Chile bajo cambio climático basados en un estudio preliminar: Modelos, incertidumbres y adaptación de la investigación para un mundo de biodiversidad dinámica / Changes in the main vegetation types of Chile predicted under climate change based on a preliminary study: Models, uncertainties and adapting research to a dynamic biodiversity world
Full Text Available Los efectos del cambio climático sobre la biodiversidad ocurren a diferentes niveles de organización (organismos, especies y ecosistemas). La vegetación se encuentra relacionada directamente con el clima, por lo que se espera que el calentamiento global altere la distribución de los tipos de vegetac [...] ión para el futuro cercano. Usando un enfoque de envoltura bioclimática, los tipos de vegetación de Chile fueron modelados y proyectados usando escenarios del IPCC para el año 2080. Los resultados presentan diferentes transiciones entre los tipos de vegetación, en relación a su distribución latitudinal y altitudinal actual. Entre los cambios principales, se identifica el avance altitudinal de la vegetación alpina, la expansión hacia el sur del desierto absoluto y del matorral desértico sobre el bosque escleróflo. Se esperan cambios en la representación relativa de las áreas protegidas dentro de los diferentes tipos de vegetación de Chile. Las limitaciones del ejercicio de modelación son discutidas junto a la necesidad de mejorar el conocimiento científico sobre procesos biológicos claves como dispersión y polinización. Abstract in english Climate change effects on biodiversity occur at different level of organization (organisms, species and ecosystems). Vegetation type bears a close relationship with climate, such that global warming is ex-pected to alter the distribution of major vegetation types in the near future. Using a bioclima [...] tic envelope modeling approach, the major vegetation types of Chile were modeled and projected using IPCC scenarios for year 2080. The results show transitions among vegetation types in relation to their current latitudinal and altitudinal distribution. Major changes include an upward shift of the alpine vegetation and southward expansion of absolute desert and desert scrub into the present area of sclerophyllous forest. Changes in the relative representation of different vegetation types in Chile´s protected areas can be expected. The limitations of modeling exercises are discussed along with need for better scientific knowledge on key biological processes such as dispersal and pollination.
Patricio, Pliscoff; Mary T. K, Arroyo; Lohengrin, Cavieres.
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.
Climate change is expected to profoundly impact terrestrial vegetation. We present a model of the projected impacts of climate change on the distribution of vegetation types in the San Francisco Bay Area using a novel application of multinomial logistic regression. Model projections are evaluated over a wide range of possible future climates, drawn from CMIP3 and CMIP5 ensembles. Evaluation of results across the entire ensemble of future climates provides the sensitivity of vegetation to changing climate, without having to choose specific future climate scenarios. Sensitivity is highly variable across the Bay Area. The single best predictor appears to be the location, in climate space, of each vegetation patch relative to the warm or dry edge of the corresponding climate envelope. It is critical to consider the equilibrium assumption underlying this, and related, modeling of vegetation impacts. The model projections are best interpreted as the long-term expected response to a particular degree of climate change, but they do not provide insight into how fast this equilibrium will be achieved or the transient states that may occur in response to rapid climate change. We combine model results with a literature survey of ecological mechanisms of vegetation change to better understand the challenges raised by disequilibrium dynamics.
Ackerly, D.; Cornwell, W.; Weiss, S. B.; Branciforte, B.; Sandel, B.; Flint, L. E.; Flint, A. L.
Full Text Available In this paper, we take the consumers in Chengdu vegetables market as samples, in the form of questionnaires and interviews, to study the consumer motivations and psychology, and make market segmentation of consumers. Results show that the consumers in Chengdu vegetables market can be divided into four types: the safety-pursuing type, the convenient and economical type, the family healthy type, and the fashionable type, among which the safety-pursuing type is the largest. Finally, authors put forward some suggestions for Chengdu vegetables market based on current conditions.
The Ecology Site Study Plan describes a field program consisting of studies which include surveys for endangered, threatened, and candidate species; vegetation characterization, including mapping and cover typing, plant succession, wetlands description, and preexisting stresses; and wildlife community characterization, including availability and quality of habitats and descriptions of mammal, bird, reptile, amphibian, and invertebrate populations. The plan for each study describes the need for the study, study design, data management and use, schedule and personnel requirements, and quality assurance. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project Requirements Document (SRP-RD). 83 refs., 3 tabs
Ro?. 17, ?. 2 (2014), s. 187-192. ISSN 1402-2001 R&D Projects: GA ?R(CZ) GAP505/11/0256 Institutional support: RVO:67985939 Keywords : succession * vegetation * restoration Subject RIV: EH - Ecology, Behaviour Impact factor: 2.416, year: 2013
Walker, L. R.; Hölzer, N.; Marrs, R.; del Moral, R.; Prach, Karel
The Natural Resources Conservation Service (NRCS) adopted the Ecological Site Description (ESD) concept in 1997. The State and Transition Model (STM) is used to describe vegetation dynamics and is an integral component of ESDs that meet users needs. NRCS is currently developing ESDs for much of the ...
The Bananal Plain spreading on the Middle Araguaia River basin in Central Brazil at the Cerrado-Amazonia ecotone is a unique system that sustains the largest seasonal wetlands of the Cerrado biome. The huge Bananal Plain is an intracratonic sedimentary basin filled with Pleistocene sediments of the Araguaia formation. Covering approximately two million hectares, the Bananal Island is a major geomorphologic feature of the Bananal plain. Fieldwork and the analysis of a temporal series of MODIS-VI and Landsat ETM images allowed us to discriminate Cerrado phyto-physiognomies on the Bananal Island. Maps of vegetation and geomorphologic units were created, and from the correlation between landforms and vegetation types we identified morpho-vegetation units. Our approach allowed us to postulate that Pleistocene landforms strongly influence, if not dominate, the distribution of vegetation units. For example, the distribution of current gallery forest is not only controlled by active floodplains, but also by alluvial belts abandoned by avulsion. Additionally, arboreal Cerrado vegetation is supported by laterite developed on the sediments of the Araguaia Formation. Some of these inactive landforms are in part modified by the present day geomorphologic processes and colonized by successional vegetation that varies from alluvial forest to Cerrado. Characterized by a very flat landscape with a hindered drainage, the muddy sediments of the Araguaia Formation and the high seasonal rainfall favor the development of regional seasonal wetlands. The Bananal plain is a key area for understanding the Quaternary climatic and biogeographic changes in tropical South America. The control exerted by relict Quaternary landforms on the current vegetation units demonstrates the strong links between geomorphologic aspects of the landscape and ecological patterns. This multidisciplinary approach provides a better understanding of the biogeographic patterns in the Cerrado-Amazon ecotone, which is useful for identifying and designing areas for conservation.
Valente, C. R.; Latrubesse, E. M.; Ferreira, L. G.
Full Text Available Abstract Background Ecological niche modeling integrates known sites of occurrence of species or phenomena with data on environmental variation across landscapes to infer environmental spaces potentially inhabited (i.e., the ecological niche to generate predictive maps of potential distributions in geographic space. Key inputs to this process include raster data layers characterizing spatial variation in environmental parameters, such as vegetation indices from remotely sensed satellite imagery. The extent to which ecological niche models reflect real-world distributions depends on a number of factors, but an obvious concern is the quality and content of the environmental data layers. Methods We assessed ecological niche model predictions of H5N1 avian flu presence quantitatively within and among four geographic regions, based on models incorporating two means of summarizing three vegetation indices derived from the MODIS satellite. We evaluated our models for predictive ability using partial ROC analysis and GLM ANOVA to compare performance among indices and regions. Results We found correlations between vegetation indices to be high, such that they contain information that overlaps broadly. Neither the type of vegetation index used nor method of summary affected model performance significantly. However, the degree to which model predictions had to be transferred (i.e., projected onto landscapes and conditions not represented on the landscape of training impacted predictive strength greatly (within-region model predictions far out-performed models projected among regions. Conclusion Our results provide the first quantitative tests of most appropriate uses of different remotely sensed data sets in ecological niche modeling applications. While our testing did not result in a decisive "best" index product or means of summarizing indices, it emphasizes the need for careful evaluation of products used in modeling (e.g. matching temporal dimensions and spatial resolution for optimum performance, instead of simple reliance on large numbers of data layers.
Ro?. 58, ?. 1 (2010), s. 69-79. ISSN 1505-2249 R&D Projects: GA MŠk(CZ) OC 350.002 Institutional research plan: CEZ:AV0Z60870520 Keywords : road-side vegetation * road ecology * life form * life history * habitat preference * alien species Subject RIV: EH - Ecology, Behaviour Impact factor: 0.542, year: 2010
The NatureServe (formerly The Nature Conservancy) has posted this publication on their Website. NatureServe offers the publication Terrestrial Vegetation of the United States in two volumes -- representing "the first standardized classification of the terrestrial ecological communities of the United States ever developed at a scale fine enough to be used in making local, site-specific conservation decisions."