Search results for "secondary succession"
showing 6 items of 26 documents
Impact of woody encroachment on soil organic carbon and nitrogen in abandoned agricultural lands along a rainfall gradient in Italy
2011
Land use changes represent one of the most important components of global environmental change andhave a strong influence on carbon cycling. As a consequence of changes in economy during the last century, areas of marginal agriculture have been abandoned leading to secondary successions. The encroachment of woody plants into grasslands, pastures and croplands is generally thought to increase the carbon stored in these ecosystems even though there are evidences for a decrease in soil carbon stocks after land use change. In this paper, we investigate the effects of woody plant invasion on soil carbon and nitrogen stocks along a precipitation gradient (200–2,500 mm) using original data from pa…
The effects of post-pasture woody plant colonization on soil and aboveground litter carbon and nitrogen along a bioclimatic transect.
2013
Abstract: We investigated the effects of woody plant colonization of abandoned pastures on soil and litter organic carbon (C) stocks and nitrogen (N) content along a bioclimatic transect in a semi-arid environment (Sicily, Italy). Soil samples were taken in three successional stages (grazed pasture, shrubland, forest) within each of three bioclimates (supramediterranean - “supra”, mesomediterranean - “meso”, thermomediterranean - “thermo”). Organic C and N in litter and soil (0-10 cm and 10-30 cm depth) were determined, as well as soil bulk density. Especially at 0-10 cm depth, changes in C and N contents along successional stages differed among bioclimates. Soil organic carbon (SOC) stock …
Dynamics of soil organic matter pools after agricultural abandonment
2014
Changes of land use from croplands to natural vegetation usually increase Carbon (C) stocks in soil. However, the contribution of old and new C to various pools still is not clearly analyzed.We measured the 13C signature of soil organic carbon (SOC) pools after vegetation change from vineyard (C3) to grassland (C4) under Mediterranean climate to assess the changes of old and new C in total SOC, microbial biomass (MB), dissolved organic C (DOC), and CO2 efflux from soil. Development of the perennial grass Hyparrhenia hirta (C4) on vineyard abandoned for 15 or 35 years ago increased C stocks for 13% and 16%, respectively (in the upper 15 cm). This increase was linked to the incorporation of n…
Afforestation and reforestation: the Sicilian case study
2014
In some regions of the world such as the Northern Hemisphere, the abandonment of agricultural land is one of the most widespread forms of land use change. In general, abandonment is followed by colonization by herbaceous and woody plants. Since the 1950s, wide areas of Southern Italy have been afforested for soil conservation improvement. In order to quantify the effects of agricultural abandonment and artificial afforestation on soil organic carbon (SOC), a dataset of 48 Sicilian sites has been analyzed. Because of their high environmental variability, these sites can be considered as representative of Southern Italy and in general of the Mediterranean basin. Soil samples were taken throug…
Vegetation dynamics on abandoned terraces of Sicily: the course and driving forces of succession
2007
In Mediterranean Europe, terrace landscapes can be found where 1) the orography is characterized by hills or mountains, 2) there is a high amount of stone outcrops and 3) the human need for agricultural production was quite high till the recent past. During the last century, many of these landscapes have been abandoned, due to their unsuitability for mechanized, intensive agriculture and due to the general land abandonment trend which arised in large parts of Europe. Since with land abandonment start secondary succession processes, the plant and animal communities linked to agroecosystems are replaced by other species which find their habitat in the developing succession stages. This proces…
Landscape-ecological and social aspects of natural afforestation of abandoned agricultural land
2013
Anda Ruskule LAUKSAIMNIECĪBAS ZEMJU AIZAUGŠANAS AINAVU EKOLOĢISKIE UN SOCIĀLIE ASPEKTI Anotācija Promocijas darbā raksturots neizmantoto lauksaimniecības zemju apmežošanās process Vidzemē, aplūkoti to ietekmējošie faktori, kā arī integrēti izvērtēti šī procesa ainavu ekoloģiskie un sociālie aspekti. Pirmo reizi Latvijā analizētas ainavas telpiskās struktūras izmaiņas, kas radušās, aizaugot lauksaimniecības zemēm. Pētījumā ir identificēti telpiskā rakstura un sugu sastāva ziņā atšķirīgi aizaugšanas tipi un izvērtēta to saistība ar dažādiem vides apstākļiem. Apzināts iedzīvotāju un ekspertu viedoklis par apmežošanās procesu, tā ietekmi uz ainavas un dabas daudzveidību, kā arī turpmākām izmant…