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Registros recuperados: 13 | |
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Odion, Dennis; Marine Science Institute, University of California, Santa Barbara; dennisodion@home.com; Tyler, Claudia; Institute for Computational Earth Systems Science; tyler@lifesci.ucsb.edu. |
Morro manazanita (Arctostaphylos morroensis) is a distinctive shrub restricted to a small area along the coast of California, USA. This endangered species faces two opposing fire-related extinction risks: (1) adults are killed by fire, and (2) recruitment opportunities only occur with fire. These strongly limit the capacity of this, as well as other obligate-seeding species, to recover from a population decline, which may result if there is an inadequate amount of time between fires for replenishment of sufficient seed populations. Using a prescribed burn, we tested whether the size of the seed bank that had accumulated in a 40-yr-old stand would prove adequate for maintaining A. morroensis population sizes through fire. Prior to the burn, we found ~11,000... |
Tipo: Peer-Reviewed Reports |
Palavras-chave: Arctostaphylos morroensis; California coast; Endangered species; Fire-dependent germination; Fire-related extinction risk; Maritime chaparral; Morro manzanita; Obligate-seeder; Postfire seedling recruitment; Seed bank; Shrublands; Viable seed. |
Ano: 2002 |
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SOUZA,M.; MÜLLER JR.,V.; KURTZ,C.; BRUNETTO,G.; COUTO,R.R.; COMIN,J.J.. |
ABSTRACT: The cultivation and deposition of cover crops residues on the soil surface can reduce weed emergence. The objective of this study was to evaluate the emergence of weeds, in a greenhouse, on a soil with cover crops in an agroecological no-tillage system. The experiment was conducted in a greenhouse with soil samples from an experiment installed in Ituporanga (Santa Catarina state). On April 2010 and 2011, the following field treatments were implemented: weed vegetation (VE), Hordeum vulgare (2010)/Avena strigosa (2011) (CV/AV), Secale cereale (CE), Raphanus sativus (NF), Secale cereale + Raphanus sativus (NF+CE) and Hordeum vulgare/Avena strigosa + Raphanus sativus (NF+AV). After the rotation of the species, the soil samples were collected in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Green manuring; Seed bank; Allium cepa. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100265 |
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Lousada,L.L.; Freitas,S.P.; Marciano,C.R.; Esteves,B.S.; Muniz,R.A.; Siqueira,D.P.. |
Soil properties can influence weed community composition and weed density agricultural area. Knowing this relationship would allow to choose the best strategy for the control of such plants. This study aimed to investigate the correlation between weed density and chemical and physical attributes of soil in three areas (UCO, USC, and UPA) for commercial sugarcane cultivation in Campos dos Goytacazes, RJ. Grids of 40 m x 40 m were established in the areas, and soil samples were collected at the intersection points for physical and chemical analysis and evaluation of the soil seed bank (SSB), followed by a phyto-sociological survey of the weeds present. Samples were collected during two periods: February/March and June/July, 2010. SSB presented the greatest... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil physics; Soil chemistry; Seed bank; Phyto-sociological survey. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000400002 |
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Medeiros,Renato Borges de; Focht,Telmo; Menegon,Leandro Luiz; Freitas,Mário Ruschel. |
The objective of this research was to evaluate the seed longevity of Eragrostis plana Nees buried at different soil depths, in a natural-grassland area in the Pampa biome (46 m altitude, 30º05´S and 51º40´W) of Rio Grande do Sul State, Brazil. The experimental design was a split-plot type in complete blocks with two factors: seeds buried at five different depth levels (soil surface and 2.5, 5, 10 and 20 cm) and seven exhumation dates. The blocks were allocated in natural grassland grazed by cattle, allocated in a 12-m-long transection. Fifty-four permeable nylon bags filled with 100 seeds in each division, with five vertical divisions, were buried in each row. Seven exhumation dates were used: the first on October 14, 2003 and the last on January 14, 2006.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biological invasion; Invader species; Pampa biome; Recovered seeds; Seed bank; Surviving seeds. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982014001100561 |
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Bechara,Fernando Campanhã; Reis,Ademir; Bourscheid,Kurt; Vieira,Neide Koehntopp; Trentin,Bruna Elisa. |
Pinus is the most invasive woody taxon, exceeded only by herbaceous plants. This study reports the reproductive biology and early establishment of Pinus elliottii Engelm. var. elliottii, describing its invasive properties in a protected natural area of the Brazilian coastal sandy plains. We evaluated the seed germination and rain, longevity of seed viability and the initial dynamics of the seedlings of Pinus elliottii var elliottii through field and laboratory experiments. We recorded a continuous seed rain of about 204.0 viable seeds m- 2 per year, with a 90 % germination rate. The seeds exhibited a low longevity of viability in the soil and a dense, permanent seedling bank that may explain the high levels of pine invasion. The environmental impact caused... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Slash pine; Germination; Seed bank; Seed rain; Seedling dynamics. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162013000200005 |
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Silveira,Fernando Augusto Oliveira; Santos,Jean Carlos; Fernandes,Geraldo Wilson. |
In this study we investigated the effects of light, temperature, and storage on seed germination of the wild pineapple Ananasananassoides, an understorey species found in cerrado woodlands. Seeds were germinated at temperatures of 15, 20, 25, 30 and 35 ºC and a 12-hr photoperiod and continuous darkness for 30-d. Seeds were photoblastic and the optimum temperatures for germination were 25 and 30 ºC. Seeds stored for 12-mo at room temperature and at 4 ºC were set to germinate at optimum conditions. Germinability of stored seeds did not differ from that of recently collected seeds, regardless of storage temperature, indicating their physiological potential for seed bank formation. Our results suggest that as in tropical rainforests, light may be an important... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cerrado; Photoblastism; Recruitment; Seed bank; Seed storage. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062010000400026 |
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Registros recuperados: 13 | |
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