scholarly journals Carbon and nitrogen stock and fluxes in coastal Atlantic Forest of southeast Brazil: potential impacts of climate change on biogeochemical functioning

2012 ◽  
Vol 72 (3 suppl) ◽  
pp. 633-642 ◽  
Author(s):  
DM Villela ◽  
EA de Mattos ◽  
AS Pinto ◽  
SA Vieira ◽  
LA Martinelli

The Atlantic Forest is one of the most important biomes of Brazil. Originally covering approximately 1.5 million of km², today this area has been reduced to 12% of its original size. Climate changes may alter the structure and the functioning of this tropical forest. Here we explore how increases in temperature and changes in precipitation distribution could affect dynamics of carbon and nitrogen in coastal Atlantic Forest of the southeast region of Brazil The main conclusion of this article is that the coastal Atlantic Forest has high stocks of carbon and nitrogen above ground, and especially, below ground. An increase in temperature may transform these forests from important carbon sinks to carbon sources by increasing loss of carbon and nitrogen to the atmosphere. However, this conclusion should be viewed with caution because it is based on limited information. Therefore, more studies are urgently needed to enable us to make more accurate predictions.

Author(s):  
André Luís de Gasper ◽  
Guilherme Salgado Grittz ◽  
Carlos Henrique Russi ◽  
Carlos Eduardo Schwartz ◽  
Arthur Vinicius Rodrigues

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
Shiyi Ou ◽  
Jing Zhang ◽  
Yong Wang ◽  
Ning Zhang

A mixture of wheat bran with maize bran as a carbon source and addition of (NH4)SO4 as nitrogen source was found to significantly increase production of feruloyl esterase (FAE) enzyme compared with wheat bran as a sole carbon and nitrogen source. The optimal conditions in conical flasks were carbon source (30 g) to water 1 : 1, maize bran to wheat bran 1 : 2, (NH4)SO4 1.2 g and MgSO4 70 mg. Under these conditions, FAE activity was 7.68 mU/g. The FAE activity on the mixed carbon sources showed, high activity against the plant cell walls contained in the cultures.


2018 ◽  
Author(s):  
Adi Lavy ◽  
David Geller McGrath ◽  
Paula B. Matheus Carnevali ◽  
Jiamin Wan ◽  
Wenming Dong ◽  
...  

AbstractWatersheds are important suppliers of freshwater for human societies. Within mountainous watersheds, microbial communities impact water chemistry and element fluxes as water from precipitation events discharges through soils and underlying weathered rock, yet there is limited information regarding the structure and function of these communities. Within the East River, CO watershed, we conducted a depth-resolved, hillslope to riparian zone transect study to identify factors that control how microorganisms are distributed and their functions. Metagenomic and geochemical analyses indicate that distance from the East River and proximity to groundwater and underlying weathered shale strongly impact microbial community structure and metabolic potential. Riparian zone microbial communities are compositionally distinct from all hillslope communities. Bacteria from phyla lacking isolated representatives consistently increase in abundance with increasing depth, but only in the riparian zone saturated sediments did we find Candidate Phyla Radiation bacteria. Riparian zone microbial communities are functionally differentiated from hillslope communities based on their capacities for carbon and nitrogen fixation and sulfate reduction. Selenium reduction is prominent at depth in weathered shale and saturated riparian zone sediments. We anticipate that the drivers of community composition and metabolic potential identified throughout the studied transect will predict patterns across the larger watershed hillslope system.


Author(s):  
Isabel P. Pais ◽  
Fernando H. Reboredo ◽  
José C. Ramalho ◽  
Maria F. Pessoa ◽  
Fernando C. Lidon ◽  
...  

Greenhouse gases content in the atmosphere significantly raised since the beginning of the industrial revolution, mainly associated to anthropogenic emissions, namely those related to altered land use. Such rise is driving changes in the climate, which will worsen throughout the 21st century. Agricultural systems are particularly vulnerable to Climate Changes (CC) thus the attempts to achieve higher crop productivities, simultaneously with more efficient use of resources, while minimizing environmental impacts could fail. The CC mitigation/adaptation measures require a major effort to decarbonise the economy, which includes a global greenhouse gas emissions reduction of ca. 50-60% by 2050, as compared to 1990. These actions should be used in a complementary manner, in order to greatly reduce the vulnerability of agri-food systems, thus, contributing to food security and safety. The water shortage and increase of extreme events episodes in Southern Europe may lead to abandonment of agricultural practices, whereas in the northern Europe it is foreseen the expansion of suitable crop´s areas and yield increases, thus emphasizing that the estimated impacts of climate changes will not be uniform throughout the world.


2020 ◽  
Vol 12 (3) ◽  
pp. 1203 ◽  
Author(s):  
Asako Iwami ◽  
Takanori Matsui ◽  
Michinori Kimura ◽  
Kenshi Baba ◽  
Mitsuru Tanaka

As the effects of climate change increase in severity, organizations across the world are attempting to measures to mitigate these effects. In accordance with the Paris Agreement of November 2015, wherein participating nations agreed to restrict the increase in global temperature below 2 °C, Japan has formulated guidelines on creating adaptation plans that can be implemented by local governments. A Climate Change Adaptive Information Platform was also launched to promote understanding and cooperation by sharing information on climate risks. However, the literature on this topic lacks information related to the organization of requirements and challenges faced by municipal administrative officials that formulate adaptation plans. To address these issues, we examined the four municipal forums hosted at Hosei University to encourage administrative needs for new technological ideas in areas such as climate modeling and impact assessment. We used text mining on the transcripts of the various workshops conducted in these forums and attempted to understand the changes in discussions and to extract issues related to the formulation process. The results showed that various topics, such as creating adaptation promotion systems, assessing the impacts of climate change, formulating adaptation plans, communicating with related organizations and stakeholders, developing human resources, and capacity building, were discussed, and a need for information, procedures, and assistance was identified for the formulation of feasible adaptation plans. This study is expected to provide a useful reference to stakeholders involved in framing adaptation plans to mitigate the effects of climate changes, particularly at the municipal level.


2009 ◽  
Vol 44 (4) ◽  
pp. 313-322 ◽  
Author(s):  
Monalisa Elshayeb ◽  
Michael D. MacKinnon ◽  
D. George Dixon ◽  
Michael Power

Abstract One strategy for reclamation of oil sands leases in northern Alberta is the construction of lakes and wetlands by capping oil sands process-affected material (OSPM) with water. To assess this approach, experimental sites containing a range of OSPM have been constructed to monitor the evolution of the resulting aquatic habitats. Stable isotopes of carbon and nitrogen were used to assess the effects of OSPM on aquatic food webs. Carbon and nitrogen isotopic signatures of sediment, dissolved inorganic and organic carbon, particulate organic matter, periphyton, plants, plankton, aquatic invertebrates, and fish were used to assess differences related to the naphthenic acid (NA) concentration in OSPM and reference sites. NAs are a principal contaminant of concern in OSPM. Sites were grouped into low (0 to 4 mg/L), medium (4 to 15 mg/L), and high (>15 mg/L) NA concentrations. There were no significant differences in food web area or length among the three NA groupings. In most cases, carbon isotope analyses of samples from low, medium, and high NA concentration sites were not significantly different, suggesting that OSPM is not a significant contributor to food web carbon sources. Significant differences were found in nitrogen isotope signatures between low, medium, and high NA sites. Ammonia from OSPM is suggested as the main contributor to δ15N enrichment.


2018 ◽  
Vol 93 (1) ◽  
pp. 71-75 ◽  
Author(s):  
B. Sures ◽  
M. Nachev ◽  
B.M. Gilbert ◽  
Q.M. Dos Santos ◽  
M.A. Jochmann ◽  
...  

AbstractThe analysis of stable isotopes of carbon and nitrogen has been used as a fingerprint for understanding the trophic interactions of organisms. Most of these studies have been applied to free-living organisms, while parasites have largely been neglected. Studies dealing with parasites so far have assessed the carbon and nitrogen signatures in endoparasites or ectoparasites of different hosts, without showing general trends concerning the nutritional relationships within host–parasite associations. Moreover, in most cases such systems involved a single host and parasite species. The present study is therefore the first to detail the trophic interactions of a freshwater monogenean–host model using δ13C and δ15N, where a single monogenean species infects two distinctly different hosts. Host fishes, Labeobarbus aeneus and Labeobarbus kimberleyensis from the Vaal Dam, South Africa, were assessed for the monogenean parasite Paradiplozoon ichthyoxanthon, individuals of which were removed from the gills of the hosts. The parasites and host muscle samples were analysed for signatures of δ13C and δ15N using an elemental analyser connected to an isotope ratio mass spectrometer. Host fish appear to use partly different food sources, with L. aeneus having slightly elevated δ13C signatures compared to L. kimberleyensis, and showed only small differences with regard to their nitrogen signatures, suggesting that both species range on the same trophic level. Carbon and nitrogen signatures in P. ichthyoxanthon showed that the parasites mirrored the small differences in dietary carbon sources of the host but, according to δ15N signatures, the parasite ranged on a higher trophic level than the hosts. This relationship resembles predator–prey relationships and therefore suggests that P. ichthyoxanthon might act as a micropredator, similar to blood-sucking arthropods such as mites and fleas.


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