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Un an apres Rio, la commission du developpement durable prend la releve.
1994
Can C-budget of natural capital be restored through conservation agriculture in a tropical and subtropical environment?
2022
De Moraes Sa, Joao Carlos | Lal, Rattan | Briedis, Clever | De Oliveira Ferreira, Ademir | Tivet, Florent | Inagaki, Thiago Massao | Potma Gonçalves, Daniel Ruiz | Canalli, Lutécia Beatriz | Bürkner dos Santos, Josiane | Romaniw, Jucimare
Conservation agriculture through no-till based on cropping systems with high biomass-C input, is a strategy to restoring the carbon (C) lost from natural capital by conversion to agricultural land. We hypothesize that cropping systems based on quantity, diversity and frequency of biomass-C input above soil C dynamic equilibrium level can recover the natural capital. The objectives of this study were to: i) assess the C-budget of land use change for two contrasting climatic environments, ii) estimate the C turnover time of the natural capital through no-till cropping systems, and iii) determine the C pathway since soil under native vegetation to no-till cropping systems. In a subtropical and tropical environment, three types of land use were used: a) undisturbed soil under native vegetation as the reference of pristine level; b) degraded soil through continuous tillage; and c) soil under continuous no-till cropping system with high biomass-C input. At the subtropical environment, the soil under continuous tillage caused loss of 25.4 Mg C ha−1 in the 0–40 cm layer over 29 years. Of this, 17 Mg C ha−1 was transferred into the 40–100 cm layers, resulting in the net negative C balance for 0–100 cm layer of 8.4 Mg C ha−1 with an environmental cost of USD 1968 ha−1. The 0.59 Mg C ha−1 yr−1 sequestration rate by no-till cropping system promote the C turnover time (soil and vegetation) of 77 years. For tropical environment, the soil C losses reached 27.0 Mg C ha−1 in the 0–100 cm layer over 8 years, with the environmental cost of USD 6155 ha−1, and the natural capital turnover time through C sequestration rate of 2.15 Mg C ha−1 yr−1 was 49 years. The results indicated that the particulate organic C and mineral associate organic C fractions are the indicators of losses and restoration of C and leading C pathway to recover natural capital through no-till cropping systems.
Afficher plus [+] Moins [-]The importance of some members of biocenosis in protecting the ecological balance on the preserved ecosystem Obedska bara [Serbia, Yugoslavia]
1997
Ratajac, R. (Poljoprivredni fakultet, Novi Sad (Yugoslavia)) | Rajkovic, D. | Stojkovic, S. | Bobic, M. | Cokic, S.
The investigations have been done in Krstonosica shaft at 3 points, in February, May and October 1995, and in January and April 1996. They included algae, Rotatoria, Copepoda, Cladocera, and Hydracarina. The species from divisio Bacillariophyta were presented most among the algal species, with 56 species, then from divisio Chlorophyta, with 26 taxons, Euglenophyta 11, Cyanobacteria 9, Pyrrophyta 3, Xanthophyta 2 and Chrysophyta 1. Among animal groups the highest number belonged to the Rotatoria group, 111 taxons have been determined. The highest number was found during autumn season (86), then in spring (73), and only 14 species in winter. The species that mostly prevailed were phytophyl species. The Cladocera group was present with 18 taxons. The phytophyl species from overgrown plants again prevailed. The Copepoda group was present with 10 species and the phytophyl species were prevailed. According to saprobiological characteristics the greatest number belongs to beta-mezosaprobionts, then oligosaprobionts. A small number of species indicates to the eutrophication process and organic pollution of water.
Afficher plus [+] Moins [-][One year after Rio meeting : works of the sustainable development committee]
1994
Anon.
Spatial planning as a tool for decreasing nitrogen loads in nature areas
1998
Bleeker, A. | Erisman, J.W. (National Institute of Public Health and the Environment (RIVM), Bilthoven (Netherlands))
Overview of JICA projects on BMA water pollution management
1987
Kiyoshi Hasegawa (Japan International Cooperation Agency (Japan))
Supra-regional biocentre Knehyne in the Beskids biogeographical region
1999
Bucek, A. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Lesnicka a Drevarska Fakulta)
(Problems caused by nitrogen - the evaluation of ecopolitical instruments)
1993
Scheele, M. (Goettingen Univ. (Germany). Inst. fuer Agraroekonomie) | Isermeyer, F. | Schmitt, G.
Der vorliegende Beitrag ist eine stark gekuerzte Fassung eines Aufsatzes von SCHEELE/ISERMEYER/SCHMITT (1992), in dem ein systematischer Ansatz fuer die Beurteilung umweltpolitischer Strategien zur Verringerung umweltgefaehrdender Stickstoffemissionen aus der Landwirtschaft vorgestellt und auf verschiedene Teilprobleme der Stickstoffproblematik angewendet wird.
Afficher plus [+] Moins [-]Macroinvertebrates in SERCON evaluation of conservation potential on the river Jegricka [Serbia] | Makroinvertebrate u SERCON proceni konzervacionog potencijala vodotoka Jegricka [Srbija]
2009
Pogrmic, S. | Jurca, T. | Mijatovic, B. | Zivic, N. | Pankov, N. | Sipos, S. | Mijic, I., Univerzitet u Novom Sadu, Novi Sad (Serbia). Prirodno-matematicki fakultet
Jegricka water body is part of the Main Drainage Channel System. The whole length of Jegricka (65 km, catchment surface 60.380 ha) is located in south part of Backa, Vojvodina Province. This highly modified water flow has become protected area since 2005 due to its specific natural features - diversity and uniqueness of biotic features, especially for birds and plants. In July 2008 survey of freshwater macroinvertebrates was conducted in order to assess water quality and conservation potential according to biotic characteristics according to conservation criteria within SERCON (System for Evaluating Rivers for Conservation) method. The aim of this paper was to evaluate the importance of macroinvertebrates as indicators of conservation potential of Jegricka water using SERCON. Results of analyses of species composition of freshwater invertebrates fauna showed presence of 12 higher taxonomic groups. Within these groups, 23 families were present at eight RHS river sections along investigated part of Jegricka water body. Togheter with SERCON based conservation criteria for macroinvertebrate, two types of biotic indices Biological Monitoring Working Party (BMWP) and Average Score Per Taxon (ASPT) were calculated in order to assess water quality. Results of the survey showed that Jegricka water body belongs probably to moderately polluted water type according to biotic indices. Results of conservation criteria Naturaless showed that observed and expected faunas are similar. Low values of SERCON family richness criteria based on whole length of water body indicate that Jegricka has low conservation potential, and that adequate rehabilitation measures should be considered in the future.
Afficher plus [+] Moins [-](Pollutant load resulting from agriculture)
1993
Frede, H.-G. (Giessen Univ. (Germany). Inst. fuer Landeskultur) | Bach, M.
Belastungen von Oberflaechengewaesser koennen grundsaetzlich von kommunalen, industriellen und landwirtschaftlichen Einleitern ausgehen. Gewaesserbelastungen aus der Landwirtschaft durch N, P und Pflanzenbehandlungsmittel treten raeumlich und zeitlich differenziert auf. Das Ausmass der jeweiligen Belastung ist unterschiedlich hoch. Mengenmaessig werden die Eintraege vom Nitrat bestimmt. Kritische Konzentrationen und Frachten treten beim Phosphor und moeglicherweise bei Pflanzenbehandlungsmitteln auf. Die Belastungsursachen sind unterschiedlich. Die Ursachen der N-Eintraege sind mengen-, pflanzen- und verteilungsspezifisch. Phosphor entstammt der Erosion. Pflanzenbehandlungsmittel werden ueber die Erosion, direkt oder ueber das Grundwasser eingetragen. Verminderungsstrategien sind generell bekannt. Sie sind auf diese unterschiedlichen Ursachen abzustimmen.
Afficher plus [+] Moins [-]