Salt marshes of Atlantic Canada: their ecology and distribution

1986 ◽  
Vol 64 (2) ◽  
pp. 455-467 ◽  
Author(s):  
Bruce A. Roberts ◽  
Alexander Robertson
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Anthropogenic Influences ◽  
Eastern Canada ◽  
Environment Management ◽  
Oil Development ◽  
The Status ◽  
Domestic Use ◽  
High Degree ◽  
Offshore Oil

This paper reviews the status of research on the Atlantic salt marshes of eastern Canada. The floristics, habitats, and biophysical aspects of the Atlantic salt marshes are described and aspects relating to anthropogenic influences on the Atlantic marshes are discussed in the context of contemporary rural settlement and vulnerability to offshore oil development. Guidelines for environment management, protection, and rehabilitation research are proposed. Such guidelines are deemed important since more than half the 33 000 ha of salt marshes in Nova Scotia have been dyked for agriculture. Most of the salt-marsh habitats in Newfoundland have a high degree of domestic grazing, even though the marshes are small in size and rare in occurrence. The least disturbed in terms of domestic use are the Labrador salt marshes which, although grazed by migratory ducks and geese, have not yet been influenced by man's activities. In addition, the Labrador salt marshes are discussed and compared with the northern marshes of arctic Canada in terms of their ecology and formation.

The Status and Prospects of Energy in China to 2005

1989 ◽  
Vol 7 (5) ◽  
pp. 306-316
Author(s):  
Zhou Feng Qi
Keyword(s):  
Growth Rate ◽  
Natural Gas ◽  
Agricultural Production ◽  
Fossil Fuels ◽  
Energy Resources ◽  
Annual Growth Rate ◽  
Oil Development ◽  
The Status ◽  
Offshore Oil ◽  
World Ranking

China's principal indigenous energy resources are: coal 800 billion tonne, hydroelectricity potential 680 GW, petroleum 60-80 billion tonne and large reserves of natural gas. Modernization of the country since 1949 has resulted in a 10% annual growth rate in the production of fossil fuels and hydroelectricity to make China third in a world ranking (912 Mtce in 1987). Forecasts for consumption in the next century are based on quadrupling industrial and agricultural production. Total demand is expected to be as high as 1450 Mtce. Coal will remain the chief source and by then nuclear is expected to contribute. Offshore oil development is receiving much attention and foreign partners are sought for its development.

Controls on salt marsh accretion: A test in salt marshes of Eastern Canada

Estuaries ◽  
2004 ◽  
Vol 27 (1) ◽  
pp. 70-81 ◽  
Author(s):  
Gail L. Chmura ◽  
Grace A. Hung
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Eastern Canada ◽  
Marsh Accretion

scholarly journals Greenhouse gas flux with reflooding of a drained salt marsh soil

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5659 ◽  
Author(s):  
Jan T. Wollenberg ◽  
Asim Biswas ◽  
Gail L. Chmura
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Anthropogenic Impacts ◽  
Ghg Emissions ◽  
Eastern Canada ◽  
Salt Marsh Restoration ◽  
Marsh Soil ◽  
Gas Flux ◽  
Lawrence Estuary ◽  
Tidal Flooding

Salt marshes are highly effective carbon (C) sinks and bury more C per square meter annually than any other ecosystem. Reclamation and anthropogenic impacts, however, have resulted in extensive losses of salt marshes. Carbon credits can be generated and sold by restoring marshes, but only if C sequestration and net reductions in greenhouse gases (GHG) are reliably quantified. Restored marshes, however, may exhibit different patterns of GHG emissions than natural marshes and it is possible that they could temporarily become sources of N2O even in the usually N-limited estuarine environment. Research on short-term GHG flux following salt marsh restoration is limited to studies of two restored marshes which examined GHG flux more than six months after the return of tidal flooding. Here we report on a laboratory experiment in which soil cores collected from a drained agricultural marsh on the St. Lawrence Estuary were flooded with estuary water. Gas flux measurements immediately after flooding revealed small increases in N2O and CH4, but a large decline in CO2 yielding, from a climatic perspective, a net cooling effect over the observation period. In addition to restoring the land’s capacity to sequester C once a marsh develops, returning tidal flooding thus appears to have the added benefit of stemming large ongoing C losses. With more than 400 km2 of undeveloped dykeland, Eastern Canada is well positioned to restore large sections of marsh and contribute to reducing atmospheric CO2 concentrations.

Urbanization impacts on production and recruitment of Fundulus heteroclitus in salt marsh creeks

2020 ◽  
Vol 645 ◽  
pp. 187-204
Author(s):  
PJ Rudershausen ◽  
JA Buckel
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Fundulus Heteroclitus ◽  
Multiple Factor Analysis ◽  
Southeastern Usa ◽  
Density Dependent ◽  
Dependent Relationship ◽  
Juvenile Abundance ◽  
The Relationship ◽  
Throw Trap

It is unclear how urbanization affects secondary biological production in estuaries in the southeastern USA. We estimated production of larval/juvenile Fundulus heteroclitus in salt marsh areas of North Carolina tidal creeks and tested for factors influencing production. F. heteroclitus were collected with a throw trap in salt marshes of 5 creeks subjected to a range of urbanization intensities. Multiple factor analysis (MFA) was used to reduce dimensionality of habitat and urbanization effects in the creeks and their watersheds. Production was then related to the first 2 dimensions of the MFA, month, and year. Lastly, we determined the relationship between creek-wide larval/juvenile production and abundance from spring and abundance of adults from autumn of the same year. Production in marsh (g m-2 d-1) varied between years and was negatively related to the MFA dimension that indexed salt marsh; higher rates of production were related to creeks with higher percentages of marsh. An asymptotic relationship was found between abundance of adults and creek-wide production of larvae/juveniles and an even stronger density-dependent relationship was found between abundance of adults and creek-wide larval/juvenile abundance. Results demonstrate (1) the ability of F. heteroclitus to maintain production within salt marsh in creeks with a lesser percentage of marsh as long as this habitat is not removed altogether and (2) a density-dependent link between age-0 production/abundance and subsequent adult recruitment. Given the relationship between production and marsh area, natural resource agencies should consider impacts of development on production when permitting construction in the southeastern USA.

Syed Nawab Haider Naqvi, Mahmood Hasan Khan and M. Ghaffu Otaudhry (edt.). LaJld Reforms in Pakistan, A Historical Perspective. Islamabad: Pakistan Institute of Development Economics 1987. viii+216 pp.Price: Rs 220 (USS 35) for hardcover; Rs 140.00 (USS 20) for soft-cover.

1988 ◽  
Vol 27 (2) ◽  
pp. 217-218
Author(s):  
Luther Tweeten
Keyword(s):  
Land Tenure ◽  
Land Reform ◽  
State Ownership ◽  
Land Reforms ◽  
Policy Makers ◽  
Rural Pakistan ◽  
The Status ◽  
Land Tenure System ◽  
Ownership Of Land ◽  
High Degree

The authors describe how Pakistan has grappled with land reform, surely one of the most intractable and divisive issues facing agriculture anywhere. The land-tenure system at independence in 1947 included a high degree of land ownership concentration, absentee landlordism, insecurity of tenant tenure, and excessive rent. Land reform since 1947 focused on imposition of ceilings on landholding, distribution of land to landless tenants and small owners, and readjustments of contracts to improve the position of the tenant. These reformist measures have removed some but by no means all of the undesirable characteristics of the system. The authors list as well as present a critique of the reports of five official committees and commissions on land reform. The reports highlight the conflicts and ideologies of the reformers. The predominant ideal of the land reformers is a system of peasant proprietorship although some reformers favoured other systems such as communal farming and state ownership of land, and still others favoured cash rents over share rents. More pragmatic reformers recognized that tenancy is likely to be with Pakistan for the foreseeable future and that the batai (sharecropping) arrangement is the most workable system. According to the editors, the batai system can work to the advantage of landlord and tenant if the ceilings on landholding can be sufficiently lowered (and enforced), the security of the tenant is ensured, and the tenant has recourse to the courts for adjudication of disputes with landlords. Many policy-makers in Pakistan have come to accept that position but intervention by the State to realize the ideal has been slow. The editors conclude that" ... the end result of these land reforms is that they have not succeeded in significantly changing the status quo in rural Pakistan" (p. 29).

scholarly journals Topological and Morphological Controls on Morphodynamics of Salt Marsh Interiors

2021 ◽  
Vol 9 (3) ◽  
pp. 311
Author(s):  
Ben R. Evans ◽  
Iris Möller ◽  
Tom Spencer
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
East Coast ◽  
Marsh Surface ◽  
Coastal Environments ◽  
Coastal System ◽  
Morphological Segmentation ◽  
The Usa ◽  
The Uk ◽  
Over Time

Salt marshes are important coastal environments and provide multiple benefits to society. They are considered to be declining in extent globally, including on the UK east coast. The dynamics and characteristics of interior parts of salt marsh systems are spatially variable and can fundamentally affect biotic distributions and the way in which the landscape delivers ecosystem services. It is therefore important to understand, and be able to predict, how these landscape configurations may evolve over time and where the greatest dynamism will occur. This study estimates morphodynamic changes in salt marsh areas for a regional domain over a multi-decadal timescale. We demonstrate at a landscape scale that relationships exist between the topology and morphology of a salt marsh and changes in its condition over time. We present an inherently scalable satellite-derived measure of change in marsh platform integrity that allows the monitoring of changes in marsh condition. We then demonstrate that easily derived geospatial and morphometric parameters can be used to determine the probability of marsh degradation. We draw comparisons with previous work conducted on the east coast of the USA, finding differences in marsh responses according to their position within the wider coastal system between the two regions, but relatively consistent in relation to the within-marsh situation. We describe the sub-pixel-scale marsh morphometry using a morphological segmentation algorithm applied to 25 cm-resolution maps of vegetated marsh surface. We also find strong relationships between morphometric indices and change in marsh platform integrity which allow for the inference of past dynamism but also suggest that current morphology may be predictive of future change. We thus provide insight into the factors governing marsh degradation that will assist the anticipation of adverse changes to the attributes and functions of these critical coastal environments and inform ongoing ecogeomorphic modelling developments.

scholarly journals Paradox of Deadwood Circular Bioeconomy in Kenya’s Public Forests

2021 ◽  
Vol 13 (13) ◽  
pp. 7051
Author(s):  
Sylvester Ngome Chisika ◽  
Joon Park ◽  
Chunho Yeom
Keyword(s):  
Social Economic ◽  
Status Quo ◽  
Forest Resource ◽  
Global Literature ◽  
Production And Consumption ◽  
Policy Suggestions ◽  
The Status ◽  
Domestic Use ◽  
Public Forests ◽  
Environmental Functions

With the rising demand for energy, the forest-based circular bioeconomy is gaining recognition as a strategy for sustainable production and consumption of forest resources. However, the forest-based bioeconomy remains underexplored from the perspective of deadwood conservation in public forests. While conducting a literature review and examining the case of Kenya, this study fills a gap in the literature to provide policy suggestions for sustainable forest resource utilization. The results from global literature indicate that deadwood performs essential social, economic, and environmental functions in the circular bioeconomy and sustainable development. Similarly, in Kenya, deadwood resources provide many socially beneficial bioproducts and services. However, the absence of scientific research and detailed guidelines for deadwood conservation may lead to the distortion of the ecological balance in public forests because of the legally sanctioned removal of deadwood, particularly firewood. Moreover, if the status quo remains, with approximately 70% of the growing population consuming deadwood for domestic use and the demand increasing, as shown by the current wood deficit in the country, there will be a major dilemma concerning whether to conserve deadwood for biodiversity or energy. Therefore, averting crisis and providing maximum deadwood value to society requires guidelines and comprehensive research in addition to a cultural and behavioral shift in energy consumption in a manner that embraces the forest-based circular bioeconomy of deadwood.

scholarly journals Mechanistic strategies of microbial communities regulating lignocellulose deconstruction in a UK salt marsh

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Daniel R. Leadbeater ◽  
Nicola C. Oates ◽  
Joseph P. Bennett ◽  
Yi Li ◽  
Adam A. Dowle ◽  
...  
Keyword(s):  
Salt Marsh ◽  
Salt Marshes ◽  
Molecular Mechanisms ◽  
Surface Sediments ◽  
Gene Profiling ◽  
Oxidative Enzymes ◽  
Lignocellulose Degradation ◽  
Rrna Gene ◽  
Enzymatic Mechanisms

Abstract Background Salt marshes are major natural repositories of sequestered organic carbon with high burial rates of organic matter, produced by highly productive native flora. Accumulated carbon predominantly exists as lignocellulose which is metabolised by communities of functionally diverse microbes. However, the organisms that orchestrate this process and the enzymatic mechanisms employed that regulate the accumulation, composition and permanence of this carbon stock are not yet known. We applied meta-exo-proteome proteomics and 16S rRNA gene profiling to study lignocellulose decomposition in situ within the surface level sediments of a natural established UK salt marsh. Results Our studies revealed a community dominated by Gammaproteobacteria, Bacteroidetes and Deltaproteobacteria that drive lignocellulose degradation in the salt marsh. We identify 42 families of lignocellulolytic bacteria of which the most active secretors of carbohydrate-active enzymes were observed to be Prolixibacteracea, Flavobacteriaceae, Cellvibrionaceae, Saccharospirillaceae, Alteromonadaceae, Vibrionaceae and Cytophagaceae. These families secreted lignocellulose-active glycoside hydrolase (GH) family enzymes GH3, GH5, GH6, GH9, GH10, GH11, GH13 and GH43 that were associated with degrading Spartina biomass. While fungi were present, we did not detect a lignocellulolytic contribution from fungi which are major contributors to terrestrial lignocellulose deconstruction. Oxidative enzymes such as laccases, peroxidases and lytic polysaccharide monooxygenases that are important for lignocellulose degradation in the terrestrial environment were present but not abundant, while a notable abundance of putative esterases (such as carbohydrate esterase family 1) associated with decoupling lignin from polysaccharides in lignocellulose was observed. Conclusions Here, we identify a diverse cohort of previously undefined bacteria that drive lignocellulose degradation in the surface sediments of the salt marsh environment and describe the enzymatic mechanisms they employ to facilitate this process. Our results increase the understanding of the microbial and molecular mechanisms that underpin carbon sequestration from lignocellulose within salt marsh surface sediments in situ and provide insights into the potential enzymatic mechanisms regulating the enrichment of polyphenolics in salt marsh sediments.

Epibiosis on eggs and brooding care in the burrowing crab Chasmagnathus granulatus (Brachyura:Varunidae): comparison between mudflats and salt marshes

2007 ◽  
Vol 87 (4) ◽  
pp. 893-901 ◽  
Author(s):  
Paola V. Silva ◽  
Tomás A. Luppi ◽  
Eduardo D. Spivak
Keyword(s):  
Salt Marsh ◽  
Filamentous Fungi ◽  
Salt Marshes ◽  
Maternal Care ◽  
Spartina Densiflora ◽  
Incubation Chamber ◽  
Stage Of Development ◽  
Key Species ◽  
Burrowing Crab ◽  
Chasmagnathus Granulatus

Chasmagnathus granulatus is a semiterrestrial intertidal burrowing crab that inhabits both the unvegetated mudflats and the cordgrass (Spartina densiflora) salt marshes in Mar Chiquita Lagoon (Argentina), where it is considered the ecologically key species. The mass of C. granulatus eggs incubated by females is colonized by epibiotic micro-organisms and accumulates detritus. The type of epibionts that use eggs as a substrate, the infestation degree, the maternal care behaviour and the protection of the incubation chamber were compared between females living on mudflats and on Spartina-dominated areas. In both places, the epibiosis by bacteria and filamentous fungi and peritrichid colonial ciliate was significantly higher in the periphery than in the centre of the brood mass. The accumulation of detritus was higher in the periphery in mudflat females but not in salt marsh females. Moreover, the level of detritus was significantly higher in mudflat than in salt marsh females only in the periphery of the brood. The infestation level of bacteria and fungi, and peritrichids, increased throughout the embryonic development only in mudflat females. The periphery of the brood mass was significantly more contaminated in mudflat than in marsh females, while the central region of the brood mass did not differ between habitats. The pleopods were significantly more contaminated by bacteria and filamentous fungi and peritrichid colonial ciliates in premoult females than in postmoult females, independently from the collection site. The percentage of females with abnormal embryos was significantly higher in mudflats (26.7%) than in marshes (12.3%). Females with late embryos spent more time flapping the abdomen and probing the embryos with the chela. Non-ovigerous females did not perform specific maternal care activities. The volume of brood mass both in early or late stage of development is greater than that of the incubation chamber and, consequently, peripheral embryos are more exposed.

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