In the present study, rainfall conditions in the Negev Desert of southern Israel during the middle Holocene are inferred from reconstruction of the past geographic distribution of C4 plants, based on isotopic analysis of organic matter in the shells
A pilot project on the potential contribution of palm-mat geotextiles to soil conservation
The use of vegetation for erosion control and environmental protection
In this pilot project, the AA. investigate the feasibility of employing palm-mat geotextiles as a potential soil conservation technique. Investigations were conducted at the Hilton Experimental Site, east Shropshire, UK, within the southern section
of the Worfe Catchment. The results suggest palm-mat application as protective buffer strips is highly effective in temperate climates.
Organic matter in tropical soils: current conditions, concerns and prospects for conservation
This article reviews the current status of organic matter in tropical soils beneath forest and savanna vegetation types and the contribution made to atmospheric carbon dioxide concentrations from decomposition processes in the soil and as a result
of tropical forest clearance. The second aim is to examine the role of soil organic matter in stabilizing soil structure, in nutrient cycling and in ion retention in tropical soils and to assess the effects of forest clearance and subsequent cultivation
on organic matter processes. The final aim is to evaluate possible practices for conserving soil organic matter and maximizing sustainability in tropical cultivation systems after deforestation.
Investigations on the northern Seward Peninsula in Alaska identified zones of recent permafrost collapse that led to the formation of floating vegetationmats along thermokarst lake margins. This paper reports on the recent expansion
of these collapse features on Lake Rhonda and Lake Owl and their geometry is determined using geophysical and remote sensing measurements. In addition, the AA. determined the extent of thawed permafrost obscured by floating vegetationmats at the study site
and provided a basis for larger scale estimates of bioavailable organic carbon in the thaw bulbs below lake portions covered by floating vegetationmats. They used high-resolution remote sensing imagery to map the spatial extent of the collapse features across
the study site, ground-penetrating radar (GPR) to noninvasively map the thickness of the floating vegetationmats and ground temperature measurements to verify the presence of a talik despite very shallow water depths.
Late Quaternary vegetation dynamics in the southern Amazon Basin inferred from carbon isotopes in soil organic matter
Amazonie ; Amérique du Sud ; Analyse isotopique ; Carbone ; Datation C 14 ; Dynamique de la végétation ; Forêt ; Holocène ; Paléo-environnement ; Quaternaire ; Savane ; Variation climatique
Amazon Basin ; C 14 dating ; Carbon ; Climatic variation ; Forest ; Holocene ; Isotope analysis ; Palaeo-environment ; Quaternary ; Savanna ; South America ; Vegetation dynamics
Carbon isotopes of soil organic matter (SOM) were used to evaluate and establish the chronology of the vegetation dynamics of an ecosystem presently composed of savannas surrounded by forests. The study was carried out on a 200-km transect along
highway BR 319, on the border of Amazonas and Rondônia states, in southern Amazon, Brazil. The results indicate that extensive forested areas existed in the Amazon during the last glaciation and that savanna vegetation expanded in response to warm and dry
Three types of geotextiles including jute mat (JM), polyester mat (PM) and polyester net (PN) were installed on slopes and their effects on erosion control and vegetation growth were investigated by both laboratory and field experiments. The results
, followed by polyester mat and polyester net. The jute mat degraded gradually and its role was replaced by that of vegetation. Thus the natural geotextile mat (jute mat) is preferred since it is more effective and more environmental friendly.
, in both 2010 and 2011. It is shown that the geotextiles improved plant growth by providing favourable soil conditions. The geotextiles were less effective in 2011 than in 2010 as a result of their degradation over time. The jute mat was most effective
This paper deals with a geochemical investigation (Rock-Eval pyrolysis) of soil organic matter sampled in a lake watershed, and the study of the sedimentary organic matter trapped in the lake deposits. The research was conducted on Chaillexon Lake
Chine ; Datation C 14 ; Dynamique de la végétation ; Formation herbacée ; Géochronologie ; Montagne ; Palynologie ; Propriétés du sol ; Pédogenèse ; Sol ; Tibet
C 14 dating ; China ; Geochronology ; Grassland ; Mountain ; Palynology ; Pedogenesis ; Soil ; Soil properties ; Tibet ; Vegetation dynamics
Vast areas on the Tibetan Plateau are covered by alpine sedge mats consisting of different species of the genus Kobresia. These mats have topsoil horizons rich in rhizogenic organic matter which creates turfs. In the core area of Kobresia pygmaea
mats around Nagqu, 4 profiles were subjected to pedological, paleobotanical and geochronological analyses concentrating on soil properties, phytogenic composition and dating of the turf. The results show that the turfs result from the transformation
Factors influencing retention of coarse particulate organic matter in streams
Bois flottant ; Cours d'eau ; Géométrie hydraulique ; Litière ; North Island ; Nouvelle-Zélande ; Rétention ; Utilisation du sol ; Végétation ; Végétation ripicole
Channel geometry ; Land use ; Litter ; New Zealand ; North Island ; Riparian vegetation ; Stream ; Vegetation
Input of terrestrial coarse particulate organic matter (CPOM : leaves and small wood,>1 mm) adds food resources and habitat to streams. The AA. investigated retention characteristics under base-flow conditions in 65 stream reaches in pasture, native
Organic matter and nutrient contents of soils under four types of bush fallow vegetation in SW Nigeria
Agropédologie ; Composition du sol ; Culture itinérante ; Culture sur brûlis ; Géographie de l'Afrique ; Longue jachère ; Matière organique ; Nigéria ; Nutriment ; Ogun ; Système de culture ; Végétation
Vegetation dynamics during the late Pleistocene in the Barreirinhas region, Maranhão State, northeastern Brazil, based on carbon isotopes in soil organic matter
Analyse isotopique ; Brésil ; Carbone ; Charbon de bois ; Dynamique de la végétation ; Maranhâo ; Matière organique ; Paléobiogéographie ; Pléistocène ; Propriétés du sol ; Quaternaire ; Sol
A vegetation transect of 78 km was studied among 4 vegetation types : Restinga (coastal vegetation), Cerrado (woody savanna), Cerradão (dense woody savanna), and Forest, as well as three forested sites around Lagoa do Caçó, located approximately 10
km of the transect. Soil profiles in this transect were sampled for δ13 C analysis, as well as buried charcoal fragments were used for 14 C dating. The vegetation dynamic inferred in this study for northeastern Brazil is in agreement with the results
Role of landscape parameters in riverine run-off, and sediment and organic matter yield on Disko Island, West Greenland
carried out almost synchronously in July 1997. Regression techniques were used to distinguish between the measured lanscape-parameters (glacier cover, altitude, slope, aspect and vegetation cover) that influence upon suspended sediment and organic matter
The AA. have tried to identify which landscape parameters influence water, sediment and organic transport from 9 drainage basins in a glacial setting on Disko Island. Measurements of water, suspended sediment and organic matter transport were
composition of bulk soil and humic acid (HA). The majority of sites in the HARC presented a soil organic matter originated from C3-vegetation and demonstrated an intense N cycling based on the δ15N data. Even though charcoal could be suggested as a component
The organic soil layer (0-35 cm) of 17 sites under high altitude rocky complexes (HARC) was sampled in eastern Brazil, in the Espinhaço and Mantiqueira Ranges, to evaluate the relationship of vegetation type and carbon and nitrogen isotopic
of soil genesis for most of the HARC sites, the raised data was not consistent to consider fire a key process for soil organic matter existence in these areas.
Late Quaternary vegetation and climate of the Wind River Range, Wyoming
Datation C 14 ; Diagramme pollinique ; Etats-Unis ; Limite supérieure de la forêt ; Montagne ; Moraine ; Palynologie ; Paléo-environnement ; Paléoclimat ; Quaternaire ; Végétation ; Wyoming
C 14 dating ; Moraine ; Mountain ; Palaeo-environment ; Palaeoclimate ; Palynology ; Pollen diagram ; Quaternary ; Tree line ; United States of America ; Vegetation ; Wyoming
Sediments from Rapid Lake document glacial and vegetation history in the Temple Lake valley of the Wind River Range, Wyoming over the past 11,000 to 12,000 yr. Radiocarbon age determinations on basal detrital organic matter from Rapid Lake
Particulate and dissolved matter in snowmelt runoff from small watersheds
Four small watersheds in central Pyrenees were studied, ranging from 0.17 to 1.4 km2 including pasture and forest vegetation. Ten variables were measured : discharge, total and organic suspended solids, total dissolved load, electrical conductivity
and/or biochemical, mainly aragonitic, precipitations. In the western part occur abundant sheet-flood detritus while gypsum precipitates within an algal mat which develops both in the intertidal and in the infratidal zones. Thus, algal mats are not absolute
Grass ley set-aside and soil organic matter dynamics on sandy soils in Shropshire, UK
The use of vegetation for erosion control and environmental protection
Erosion plot studies at the Hilton Experimental Site, east Shropshire, have evaluated the effects of set-aside on runoff and erosion. The fundamental objectives of this paper are to : present results of long-term soil organic matter (SOM) changes
Relation of soil organic matter concentration to climate and altitude in zonal soils of China
With a total of 886 data sets distributed in different regions of China, the relation of soil organic matter (SOM) concentration to climate and altitude was investigated. According to climate gradient and vegetation community succession, 6