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The usefulness of a long-term perspective in assessing current forest conservation management in the Apuseni Natural Park, Romania 总被引:3,自引:0,他引:3
The forest ecosystem of the Apuseni National Park (ANP) in NW Romania is recognized for its high species and genetic diversity and is protected through various conservation measures. As ANP is the most populated natural park in Romania, the focus is on the need for communities to manage, sustain and prosper by using, exploring and sustaining the natural resources. But what activities are the most appropriate for the conservation of a highly diverse natural forest? This paper presents results from a long-term ecological study using fossil pollen, microscopic and macroscopic charcoal and AMS14C dating on a site in the ANP in order to examine how the interaction between climate change, human activities and other disturbances have shaped the present protected landscapes over the last 5700 years in this part of the reserve. Results from this study show that the landscape in this region has been continuously forested over the last 5700 years BP, but the forest composition and structure have been dynamic throughout much of the time. In particular, distinct changes in forest composition have occurred over the last 700 years of the record. Fagus sylvatica was the major taxon between 5200 and 200 years BP and its dominance is associated with the highest forest stability. The formation of the current Picea abies forests started 400 years ago and spruce became the dominant forest species during the last two centuries as a result of selective forest clearance, intensive grazing, and more recently, plantations. This led to a large reduction in forest diversity, decline of F. sylvatica and local extinction of several species including Abies alba, Ulmus, Tilia, and Acer. Our results show the high conservation values of A. alba and F. sylvatica in the ANP. Current management practices that allow the anthropogenic activities of timber production and fast tree regeneration, usually involving the plantation of P. abies in this part of the ANP are not in keeping with the NATURA 2000 objectives of ensuring the persistence of the most vulnerable species and habitats. 相似文献
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Barbosa BF Gomes AO Ferro EA Napolitano DR Mineo JR Silva NM 《Veterinary parasitology》2012,187(1-2):44-52
Currently, toxoplasmosis is treated with sulfadiazine and pyrimethamine. However, this treatment presents several adverse side effects; thus, there is a critical need for the development and evaluation of new drugs, which do not present the same problems of the standard therapy. Enrofloxacin is a fluoroquinolone antibiotic known to control infection against several bacteria in veterinary medicine. Recently, this drug has demonstrated protective effects against protozoan parasites such as Neospora caninum. The present study aimed to determine the effect of enrofloxacin in the control of Toxoplasma gondii infection. For this purpose, human foreskin fibroblast (HFF) cells were infected with T. gondii RH strain and treated with sulfadiazine, penicillin/streptomycin, pyrimethamine, or enrofloxacin. Following treatment, we analyzed the infection index, parasite intracellular proliferation and the number of plaques. Additionally, tissue parasitism and histological changes were investigated in the brain of Calomys callosus that were infected with T. gondii (ME49 strain) and treated with either sulfadiazine or enrofloxacin. Enrofloxacin was able to reduce the infection index, intracellular proliferation and the number of plaques in HFF cells infected by T. gondii in comparison with untreated or penicillin/streptomycin-treated ones. Enrofloxacin was more protective against T. gondii in HFF infected cells than sulfadiazine treatment (P<0.001). In addition, pyrimethamine, enrofloxacin or the associations of sulfadiazine plus pyrimethamine, enrofloxacin plus sulfadiazine or enrofloxacin plus pyrimethamine-treatments were able to reduce the plaque numbers in HFF cells infected by T. gondii when compared to medium, penicillin/streptomycin or sulfadiazine alone. In vivo experiments demonstrated that enrofloxacin diminished significantly the tissue parasitism as well as the inflammatory alterations in the brain of C. callosus infected with T. gondii when compared with untreated animals. Based on our findings, it can be concluded that enrofloxacin is a potential alternative drug for the treatment of toxoplasmosis. 相似文献
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Suarez Luz Angelica Robson Andrew McPhee John O’Halloran Julie van Sprang Celia 《Precision Agriculture》2020,21(6):1304-1326
Precision Agriculture - Proximal and remote sensors have proved their effectiveness for the estimation of several biophysical and biochemical variables, including yield, in many different crops.... 相似文献
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Catherine Dogimont Angelica Bussemakers Jérôme Martin Sofiane Slama Hervé Lecoq Michel Pitrat 《Euphytica》1997,96(3):391-395
The genetic control of resistance to cucurbit aphid-borne yellows luteovirus (CABYV) in Cucumis melo L. was studied in three
progenies obtained from the cross between a resistant Indian line, PI 124112, and a susceptible cultivar of Charentais type,
Védrantais. An F2 progeny and recombinant inbred lines were screened respectively in 1993 and 1995 under natural infection
conditions in open field at Montfavet, France whereas the back cross (PI 124112 × F1) was inoculated by viruliferous Myzus
persicae in controlled conditions. ELISA was used for assessing degree of virus multiplication in the plants resistance. In
the three trials performed, segregation analysis were consistent with the hypothesis that the resistance to CABYV in PI 124112
is conferred by two independent complementary recessive genes, for which the symbols cab-1 and cab-2T are proposed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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High diagnostic accuracy of the Sysmex XT‐2000iV delta total nucleated cells on effusions for feline infectious peritonitis 下载免费PDF全文
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Bitencourt MA Dantas GR Lira DP Barbosa-Filho JM de Miranda GE Santos BV Souto JT 《Marine drugs》2011,9(8):1332-1345
The regulation of the inflammatory response is essential to maintaining homeostasis. Several studies have investigated new drugs that may contribute to avoiding or minimizing excessive inflammatory process. The aim of this study was to evaluate the effect of extracts of green algae Caulerpa mexicana on models inflammation. In mice, the inflammatory peritonitis model is induced by zymosan. Previous treatment of mice with aqueous and methanolic extracts of C. mexicana was able to suppress the cell migration to the peritoneal cavity, in a time-dependent but not in a dose-dependent manner. The treatment of mice with C. mexicana extracts also decreased the xylene-induced ear edema, exerting strong inhibitory leukocyte migration elicited by zymosan into the air pouch. We concluded that administration of the extracts resulted in a reduction of cell migration to different sites as well as a decrease in edema formation induced by chemical irritants. This study demonstrates for the first time the anti-inflammatory effect of aqueous and methanolic extracts from the green marine algae Caulerpa mexicana. 相似文献
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