Mangrove blue carbon stocks and dynamics are controlled by hydrogeomorphic settings and land‐use change

Globally, carbon‐rich mangrove forests are deforested and degraded due to land‐use and land‐cover change (LULCC). The impact of mangrove deforestation on carbon emissions has been reported on a global scale; however, uncertainty remains at subnational scales due to geographical variability and field data limitations. We present an assessment of blue carbon storage at five mangrove sites across West Papua Province, Indonesia, a region that supports 10% of the world's mangrove area. The sites are representative of contrasting hydrogeomorphic settings and also capture change over a 25‐years LULCC chronosequence. Field‐based assessments were conducted across 255 plots covering undisturbed and LULCC‐affected mangroves (0‐, 5‐, 10‐, 15‐ and 25‐year‐old post‐harvest or regenerating forests as well as 15‐year‐old aquaculture ponds). Undisturbed mangroves stored total ecosystem carbon stocks of 182–2,730 (mean ± SD: 1,087 ± 584) Mg C/ha, with the large variation driven by hydrogeomorphic settings. The highest carbon stocks were found in estuarine interior (EI) mangroves, followed by open coast interior, open coast fringe and EI forests. Forest harvesting did not significantly affect soil carbon stocks, despite an elevated dead wood density relative to undisturbed forests, but it did remove nearly all live biomass. Aquaculture conversion removed 60% of soil carbon stock and 85% of live biomass carbon stock, relative to reference sites. By contrast, mangroves left to regenerate for more than 25 years reached the same level of biomass carbon compared to undisturbed forests, with annual biomass accumulation rates of 3.6 ± 1.1 Mg C ha^?1 year^?1. This study shows that hydrogeomorphic setting controls natural dynamics of mangrove blue carbon stocks, while long‐term land‐use changes affect carbon loss and gain to a substantial degree. Therefore, current land‐based climate policies must incorporate landscape and land‐use characteristics, and their related carbon management consequences, for more effective emissions reduction targets and restoration outcomes.     

The global translation profile in a ribosomal protein mutant resembles that of an eIF3 mutant

Background

Genome-wide assays performed in Arabidopsis and other organisms have revealed that the translation status of mRNAs responds dramatically to different environmental stresses and genetic lesions in the translation apparatus. To identify additional features of the global landscape of translational control, we used microarray analysis of polysomal as well as non-polysomal mRNAs to examine the defects in translation in a poly(A) binding protein mutant, pab2 pab8, as well as in a mutant of a large ribosomal subunit protein, rpl24b/shortvalve1.

Results

The mutation of RPL24B stimulated the ribosome occupancy of mRNAs for nuclear encoded ribosomal proteins. Detailed analysis yielded new insights into the translational regulon containing the ribosomal protein mRNAs. First, the ribosome occupancy defects in the rpl24b mutant partially overlapped with those in a previously analyzed initiation factor mutant, eif3h. Second, a group of mRNAs with incomplete coding sequences appeared to be uncoupled from the regulon, since their dependence on RPL24B differed from regular mRNAs. Third, different sister paralogs of the ribosomal proteins differed in their translation state in the wild-type. Some sister paralogs also differed in their response to the rpl24b mutation. In contrast to rpl24b, the pab2 pab8 mutant revealed few gene specific translational defects, but a group of seed storage protein mRNAs were stimulated in their ribosome occupancy. In the course of this work, while optimizing the statistical analysis of ribosome occupancy data, we collected 12 biological replicates of translation states from wild-type seedlings. We defined 20% of mRNAs as having a high variance in their translation state. Many of these mRNAs were functionally associated with responses to the environment, suggesting that subtle variation in the environmental conditions is sensed by plants and transduced to affect the translational efficiency of hundreds of mRNAs.

Conclusions

These data represent the first genome-wide analysis of translation in a eukaryote defective in the large ribosomal subunit. RPL24 and eIF3h play similar but non-identical roles in eukaryotic translation. The data also shed light on the fine structure of the regulon of ribosomal protein mRNAs.

     

The status of research on the mammals of Sulawesi,Indonesia

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Beam forming of ultra-wideband pulses by a complex-valued spatio-temporal multilayer neural network

We present a neuro-beam former of ultra-wideband (UWB) pulses employing complex-valued spatio-temporal multilayer neural network, where complex-valued back propagation through time (CV-BPTT) is used as a learning algorithm. The system performance is evaluated with a UWB mono-cycle pulse. Simulation results in suppressing multiple UWB interferes and in steering to multiple desired UWB pulses, demonstrates the applicability of the proposed system.     

Cervical Cancer Screening Service Uptake and Associated Factors among Age Eligible Women in Mekelle Zone,Northern Ethiopia, 2015: A Community Based Study Using Health Belief Model

Introduction

Cervical cancer is the third most common cancer among women worldwide, with about 500,000 new patients diagnosed and over 250,000 deaths every year. Cervical cancer screening offers protective benefits and is associated with a reduction in the incidence of invasive cervical cancer and cervical cancer mortality. But there is very low participation rate in screening for cervical cancer among low and middle-income countries.

Objective

This study aimed to determine cervical cancer screening service uptake and its associated factor among age eligible women in Mekelle zone, northern Ethiopia, 2015.

Methods

A community based cross-sectional study was conducted in Mekelle zone among age eligible women from February to June 2015. Systematic sampling technique was used to select 1286 women in to the study. A pre-tested structured questionnaire was used to collect relevant data. Data was entered and cleaned using EPINFO and analyzed using SPSS version 20 software package. Bivariate and Multivariate logistic regression was performed to assess association between dependent and independent variables with 95% CI and p-value less than 0.05 was set for association.

Results

The study revealed that among 1186 age eligible women, only 235(19.8%) have been screened for cervical cancer. Age (AOR = 1.799, 95%CI = 1.182–2.739), history of multiple sexual partners (AOR = 1.635, 95%CI = 1.094–2.443), history of sexually transmitted disease (AOR = 1.635,95%CI = 1.094–2.443), HIV sero status (AOR = 5.614, 95%CI = 2.595–12.144), perceived susceptibility to cervical cancer (AOR = 2.225, 95%CI = 1.308–3.783), perceived barriers to premalignant cervical lesions screening (AOR = 2.256, 95%CI = 1.447–3.517) and knowledge on cervical cancer and screening (AOR = 2.355, 95%CI = 1.155–4.802) were significant predictors of cervical cancer screening service uptake.

Conclusion

Magnitude of cervical cancer screening service uptake among age eligible women is still unacceptably low. Age of the women, history of multiple sexual partners and sexually transmitted disease, HIV sero-positivity, Knowledge, Perceived susceptibility and Perceived Barrier were important predictors of cervical cancer screening service uptake.     

Independent origins of tetraploid cryptic species in the fern <Emphasis Type="Italic">Ceratopteris thalictroides</Emphasis>

Ceratopteris thalictroides (L.) Brongn is a tetraploid fern species that contains at least three cryptic species, the south, the north and the third type. In this study we combined data from both chloroplast DNA (cpDNA) and nuclear DNA sequences of three diploid species and three cryptic species of C. thalictroides to unravel the origin of the cryptic species, particularly of the reticulate relationships among the diploid and tetraploid taxa in the genus Ceratopteris. Of the three diploid species examined, C. cornuta had cpDNA identical to that of the tetraploid third type plants, and this diploid species is a possible maternal ancestor of the tetraploid third type. Analysis of the homologue of the Arabidopsis thaliana LEAFY gene (CLFY1) identified ten alleles in the genus Ceratopteris, with six alleles found in C. thalictroides. The unrooted tree of the CLFY1 gene revealed four clusters. Each cryptic species showed fixed heterozygosity at the CLFY1 locus and had two alleles from different clusters of the CLFY1 tree. Consideration of the cpDNA sequences, CLFY1 genotypes of the cryptic species and CLFY1 gene tree in concert suggested that the cryptic species of C. thalictroides had originated through independent allopolyploidization events involving C. cornuta and two unknown hypothetical diploid species.