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Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

The coastal saltmarshes in China have been seriously degraded and artificial restoration strategies have become one of the primary measures to protect the coastal habitats. In this study, we investigated efficient restoration techniques for native saltmarsh plants in vacant habitats within the project area of the Ecological Control of Spartina alterniflora and Improvement of Birds Habitats in the Shanghai Chongming Dongtan Bird National Nature Reserve in the Yangtze Estuary. Through field and pilot experiments, we analyzed the effects of propagule types and transplanting methods on the restoration efficiency of Scirpus mariqueter, a dominant saltmarsh species in the Yangtze Estuary. We further evaluated the cost and efficiency of various restoration strategies. Our results indicated that: 1) The corm seedlings of S. mariqueter had higher flood tolerance, and were suitable for use in the habitats with higher environmental heterogeneity. 2) Across the four treatments for S. mariqueter restoration, the most economically efficient treatment was to transplant low-density corm seedlings without sediment, with an investment cost of approximately ¥ 10100 per hectare. The costs were ¥41100, ¥30000, and ¥ 120100 per hectare for high-density without sediment, low-density with sediment, and high-density with sediment restoration, respectively. 3) After nearly 5-yr efforts, the S. mariqueter community of Plot C3 in project area had achieved a coverage of over 60%, marking a relatively successful large-scale field restoration. This study could provide the foundation and support for large-scale coastal saltmarsh restoration projects. [ABSTRACT FROM AUTHOR] more...

The loss of plant biodiversity, particularly rare and endangered species, represents a global threat, with extinction rates 1,000 to 10,000 times higher than natural levels. This crisis is driven by anthropogenic activities such as deforestation, land-use change, over-exploitation, and illegal harvesting, alongside other factors like invasive species, climate change, and habitat fragmentation. Their imminent extinction, vital for ecosystems and human resources, underscores the need for an effective conservation strategy to prevent irreversible genetic diversity loss. To address this issue, beyond the conventional low-efficiency, high-cost, and short-term storage methods such as in situ conservation, plant cryobanking—a deep-freezing technology—offers a viable solution for preserving plant species by significantly slowing down cellular metabolism for long-term storage, potentially lasting hundreds of years. While cryobanking has traditionally focused on economically important crops, rare and endangered species require more serious attention. This review delves into cryobanking efforts for these species, focusing on techniques and the genetic stability of diverse plant materials. It also explores the advantages and disadvantages of cryobanking cells, meristems, embryos, buds, and seeds. Meanwhile, it reveals that sexual propagules like seeds and pollen, as the most convenient and accessible forms, along with the shoot apex as the primary asexual unit, are commonly used for cryopreservation. Furthermore, sexual desiccation-tolerant propagules can be easily cryopreserved with high survival rates through desiccation and freezing in liquid nitrogen, while asexual ones show different responses to various cryopreservation methods, necessitating further research. Various morphological, cytological, biochemical, and molecular markers were also examined regarding the importance of genetic stability of rare and endangered cryopreserved plants. This review reveals that molecular markers like RAPD, SSR, and AFLP are most effective in detecting even the smallest DNA changes, while morphological markers, though less effective, offer supplementary information. However, the lack of necessary protocols and technologies from sampling to storage, combined with limited efforts and experience in cryobanking despite the significant species diversity, and a lack of global foresight, underscores the need for a comprehensive approach to the effective cryobanking of these valuable plants. By carefully examining recent research findings and biobank reports, this comprehensive review aims to improve the technological understanding of this efficient ex situ conservation method in cryostoring different plant materials while maintaining their genetic stability. It seeks to assist governments, gene banks, and germplasm managers make informed decisions regarding prioritizing conservation programs for rare and endangered plant species. [ABSTRACT FROM AUTHOR] more...

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Copyright of Biota Neotropica (Edicao em Iingles) is the property of Biota Neotropica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Patterns of elevational distribution of alien plant species in the southern Sierra Nevada of California were used to test the hypothesis that alien plant species invading high elevations around the world are typically climate generalists capable of growing across a wide elevational range. The Sierra Nevada has been heavily impacted for more than a century and a half, first by heavy grazing up into high elevation meadows, followed by major logging, and finally, by impacts associated with recreational use. The comparative elevational patterns of distribution and growth form were compared for native and alien plant species in the four families (Asteraceae, Brassicaceae, Fabaceae, and Poaceae) that contribute the majority of naturalized aliens in the study area. The distribution of realized climatic niche breadth, as measured by elevational range of occurrence, was virtually identical for alien and native species, with both groups showing a roughly Gaussian distribution peaking with species whose range covers a span of 1500-1999 m. In contrast to alien species, which only rarely occurred at higher elevations, native species showed a distribution of upper elevation limits peaking at 3000-3499 m, an elevation that corresponds to the zone of upper montane and subalpine forests. Consistent with a hypothesis of abiotic limitations, only a few alien species have been ecologically successful invaders at subalpine and alpine elevations above 2500 m. The low diversity of aliens able to become established in these habitats is unlikely due to dispersal limitations, given the long history of heavy grazing pressure at high elevations across this region. Instead, this low diversity is hypothesized to be a function of life history traits and multiple abiotic stresses that include extremes of cold air and soil temperature, heavy snowfall, short growing seasons, and low resource availability. These findings have significant implications for resource managers. [ABSTRACT FROM AUTHOR] more...

The article discusses a study in which the propagule method was used to investigate the development of foraminiferal assemblages under different environmental conditions. The propagule method involved experimental arrays where foraminifera were grown from propagule banks under different controlled abiotic conditions. The foraminiferal assemblages studied were collected from mudflats on Sapelo Island in Georgia. The study examined the roles played by temperature, salinity and site in structuring coastal foraminifera communities. The impact of climate change on coastal foraminiferal assemblages is explained. more...

Abstract: One of the most serious problems caused by eutrophication of shallow lakes is the disappearance of submerged macrophytes and the switch to a turbid, phytoplankton-dominated state. The reduction of external nutrient loads often does not result in a change back to the macrophyte-dominated state because stabilising mechanisms that cause resilience may delay a response. Additional internal lake restoration measures may therefore be needed to decrease the concentration of total phosphorus and increase water clarity. The re-establishment of submerged macrophytes required for a long-term stability of clear water conditions, however, may still fail, or mass developments of tall-growing species may cause nuisance for recreational use. Both cases are often not taken into account when restoration measures are planned in Germany, and existing schemes to reduce eutrophication consider the topic inadequately. Here we develop a step-by-step guideline to assess the chances of submerged macrophyte re-establishment in shallow lakes. We reviewed and rated the existing literature and case studies with special regard on (1) the impact of different internal lake restoration methods on the development of submerged macrophytes, (2) methods for the assessment of natural re-establishment, (3) requirements and methods for artificial support of submerged macrophyte development and (4) management options of macrophyte species diversity and abundance in Germany. This guideline is intended to help lake managers aiming to restore shallow lakes in Germany to critically asses and predict the potential development of submerged vegetation, taking into account the complex factors and interrelations that determine their occurrence, abundance and diversity. [Copyright &y& Elsevier] more...

Abstract: The effect of density on the growth, recruitment of new ramets, biomass allocation, rhizome spacer length and rhizome branching of the submersed macrophyte Potamogeton perfoliatus L. was experimentally evaluated in a mesocosm with three different initial shoot densities. The findings suggest that the number of primary shoots available in the beginning of the season can strongly influence patterns of growth and clonal reproduction. In contrast to many studies that found decreasing production parameters with plant density, ramet and biomass production of Potamogeton perfoliatus plants were highest at medium plant density. This is probably due to negative feed-back through crowding at high density and unclear negative effects at low density. Shoot allocation tended to increase with density, rhizome allocation tended to decrease with density and root biomass remained unchanged. At low density Potamogeton perfoliatus produced longer rhizome spacers and more branchings than at higher densities. Shorter rhizome spacers at high plant density probably restrict patch expansion and cause discrete patch shapes. A likely mechanism for plastic changes in clonal architecture is increasing competition for light at increasing density, but other density-dependent factors may also contribute. Investigations on propagule numbers of tubers and turions show that self-regulation of ramet number was associated with self-regulation of propagule number in both Potamogeton perfoliatus and Potamogeton pectinatus, with higher densities producing less propagules per plant. [Copyright &y& Elsevier] more...

The article discusses a study on the propagules of benthic marine organisms' dispersal distance and development of criteria for marine reserves design in the U.S. The dispersal of propagules affects the population by maintaining the continuity of genetic or flow of gene between separated populations, and sustaining a new recruits in the populations, are also included. more...

This work proposes the use of a biomaterial sodium alginate for microencapsulating stonewort oospores. The microencapsulation method has been adopted and optimized to improve research work carried out on the oospores. A detailed protocol for the production of microcapsules with stonewort oospores has been presented, with particular attention paid to the critical stages and factors interfering with the efficient production process. The advantages and disadvantages of this method have also been indicated. Microcapsules with oospores can be successfully used in various laboratory (observation of the germination phases) and field experiments (reintroduction of rare species of stonewort). Alginate microcapsule may consist of water taken directly from the habitat of the stonewort, a medium, as well as specific additives (antibiotics or fungicides). The hardness of the encasement is regulated by the concentration of the sodium alginate. The optimum alginate concentration for oospores is between 2 and 3%. Encasements produced with less than 2% sodium alginate concentration do not form circular microcapsules during gelation. On the other hand, concentration >3% may limit the oospores' ability to germinate (higher density of the microcapsule). In such a dense environment, the germinating primary cells may encounter difficulties in outgrowing the microcapsule. It has been shown that alginate encasement creates an effective protective layer for the oospores inside it. The oospore is protected from mechanical damage as well as from direct exposure to the external environment; especially from pathogens and other microorganisms that can inhibit its germination and limit the growth of the protonemal and primary rhizoidal cell. The main application of oospore microencapsulation using sodium alginate is facilitating further mechanical manipulations of oospores, which by nature are very small structures (max. length 1 mm), while a microcapsule with an oospore embedded inside it can have a diameter from 3 to 5 mm (as required). Unlabelled Image • Microencapsulation of oospores opens up new research possibilities for stoneworts. • Oospores in microcapsule are protected from mechanical damage and pathogen infection. • Microencapsulation of oospores facilitates work at the laboratory and in the field. • Microcapsules allow control of factors that induce/inhibit germination of oospores. • Microcapsules can be helpful in the process of reintroducing rare stoneworts. [ABSTRACT FROM AUTHOR] more...

Early stages of macroalgae are known to be more vulnerable to changes in the abiotic environment than their adult phases. However, in algal groups attaining intricate life-cycles, the ecophysiological responses of haploid and diploid propagules have not been sufficiently studied. In the present study, stress responses of haploid tetraspores and diploid carpospores of sub-Antarctic red alga Mazzaella laminarioides exposed to ultraviolet (UV) radiation were studied. We tested the hypothesis that UV stress responses of two types of spores attaining similar size are determined by light use characteristics by comparing the photobiological and bio-optical traits. Fluorescence-based photosynthetic efficiency was measured during a 5- h exposure and after a 5- h recovery. Germination and growth of spores exposed to UV treatments were also assessed. Diploid carpospores exhibited higher chlorophyll a content and higher absorption in the UV band than tetraspores. Although the maximal quantum yield was higher in carpospores than tetraspores, no differences in light demands were detected. Exposure to photosynthetically active radiation (PAR) caused inhibition of photosynthetic activity only in carpospores (43%), while exposure to a combination of PAR + UV reduced the maximal quantum yield significantly in tetraspores (36%) and carpospores (60%). In both types of spores, a recovery from UV stress was observed, allowing their germination and further development. The different responses to radiation found in haploid and diploid propagules highlight the ecophysiological versatility of different life-cycle phases to cope with light stress factors ensuring finally successful recruitment and survival. • Diploid and haploid spores of M. laminarioides exhibit slight size difference. • Both types of spores differ in bio-optical traits and respond differently to UV. • Besides the differences, both types of spores retain the capacity of germination. • This versatility ensures successful recruitment of haploid and diploid phases. [ABSTRACT FROM AUTHOR] more...