scholarly journals Early Selection of Tree Species for Regeneration in Degraded Woodland of Southeastern Congo Basin

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 117
Author(s):  
Jean Marc Kaumbu Kyalamakasa ◽  
Michel Mpundu Mubemba Mulambi ◽  
Emery Kasongo Lenge Mukonzo ◽  
Mylor Ngoy Shutcha ◽  
Honoré Tekeu ◽  
...  
Keyword(s):  
Biomass Allocation ◽  
Tree Species ◽  
Early Stage ◽  
Group Versus ◽  
Seedling Development ◽  
Congo Basin ◽  
Successional Status ◽  
Seedling Survivorship ◽  
Productive Potential ◽  
Growth Differences

Miombo woodland (MW) has several multi-purpose forest species, which are over-exploited for agriculture, charcoal and logging. Industrial plantations are among the promising solutions for sustainable management of MW, but high-yielding MW species are still lacking in the forestry sector. In this context, the present study assessed the growth of MW species, with respect to their early (ES) or late (LS) successional status. Seedling development was assessed for eight tree species, which were ES (Combretum collinum, Pterocarpus tinctorius) and LS (Brachystegia boehmii, B. longifolia, B. spiciformis, B. wangermeana, Julbernardia globiflora, J. paniculata), 1, 2 and 4 years after planting. Germination and survival varied in relation to ontogenetic traits of the species, but not the successional status, as was the case for growth and productivity. Seed germination was 60% to 88% for all species (except C. collinum). Seedling survivorship was greater than 70% for most species, except for J. paniculata (36%). ES species have greater growth compared to LS, due to the allocation of biomass to diameter and the length of the root, respectively, from the early stage of seedling development. These two strategies of biomass allocation are positively correlated with height. We further observed two distinct phases of seedling development (0–2 and 2–4 years) for all species. Growth differences among LS species were identified 4 years after planting. Based on seedling biomass, B. spiciformis, C. collinum and P. tinctorius are the most productive potential candidates for reforestation of degraded MW. We concluded that seedling growth and productivity varied according to strategies of biomass allocation that were related to successional status (ES (Chipya group) versus LS (Miombo group)) and to age following planting.

scholarly journals Seed germination and seedling development in response to submergence in tree species of the Central Amazonian floodplains

AoB Plants ◽  
2015 ◽  
Vol 7 ◽  
Author(s):  
Risolandia Bezerra de Melo ◽  
Augusto César Franco ◽  
Clovis Oliveira Silva ◽  
Maria Teresa Fernandez Piedade ◽  
Cristiane Silva Ferreira
Keyword(s):  
Seed Germination ◽  
Tree Species ◽  
Seedling Development

scholarly journals Experimental sand burial affects seedling survivorship, morphological traits, and biomass allocation of <i>Ulmus pumila</i> var. <i>sabulosa</i> in the Horqin Sandy Land, China

Solid Earth ◽  
2016 ◽  
Vol 7 (4) ◽  
pp. 1085-1094 ◽  
Author(s):  
Jiao Tang ◽  
Carlos Alberto Busso ◽  
Deming Jiang ◽  
Ala Musa ◽  
Dafu Wu ◽  
...  
Keyword(s):  
Biomass Allocation ◽  
Morphological Traits ◽  
Seedling Emergence ◽  
Relative Mass ◽  
Seedling Height ◽  
Horqin Sandy Land ◽  
Sandy Land ◽  
Ulmus Pumila ◽  
Sand Burial ◽  
Seedling Survivorship

Abstract. As a native tree species, Ulmus pumila var. sabulosa (sandy elm) is widely distributed in the Horqin Sandy Land, China. However, seedlings of this species have to withstand various depths of sand burial after emergence because of increasing soil degradation, which is mainly caused by overgrazing, climate change, and wind erosion. An experiment was conducted to evaluate the changes in its survivorship, morphological traits, and biomass allocation when seedlings were buried at different burial depths: unburied controls and seedlings buried vertically up to 33, 67, 100, or 133 % of their initial mean seedling height. The results showed that partial sand burial treatments (i.e., less than 67 % burial) did not reduce seedling survivorship, which still reached 100 %. However, seedling mortality increased when sand burial was equal to or greater than 100 %. In comparison with the control treatment, seedling height and stem diameter increased at least by 6 and 14 % with partial burial, respectively. In the meantime, seedling taproot length, total biomass, and relative mass growth rates were at least enhanced by 10, 15.6, and 27.6 %, respectively, with the partial sand burial treatment. Furthermore, sand burial decreased total leaf area and changed biomass allocation in seedlings, partitioning more biomass to aboveground organs (e.g., leaves) and less to belowground parts (roots). Complete sand burial after seedling emergence inhibited its re-emergence and growth, even leading to death. Our findings indicated that seedlings of sandy elm showed some resistance to partial sand burial and were adapted to sandy environments from an evolutionary perspective. The negative effect of excessive sand burial after seedling emergence might help in understanding failures in recruitments of sparse elm in the study region.

Treatment Outcomes in Completely Resected Stage I to Stage IV Uterine Carcinosarcoma With Rhabdomyosarcoma Differentiation

2013 ◽  
Vol 23 (9) ◽  
pp. 1635-1641 ◽  
Author(s):  
Vicky Makker ◽  
Sara J. Kravetz ◽  
Jacqueline Gallagher ◽  
Oana-Paula Orodel ◽  
Qin Zhou ◽  
...  
Keyword(s):  
Adjuvant Chemotherapy ◽  
Early Stage ◽  
Group Versus ◽  
Stage Iv ◽  
Stage I ◽  
Cancer Center ◽  
Uterine Carcinosarcoma ◽  
Entire Cohort ◽  
Gynecology And Obstetrics ◽  
Resected Stage

ObjectiveTo evaluate overall survival (OS) and progression-free survival (PFS) after adjuvant therapy in stage I to stage IV uterine carcinosarcoma with rhabdomyosarcoma differentiation.MethodsMemorial Sloan-Kettering Cancer Center medical records from 1990 to 2012 were reviewed. Patients who received chemotherapy with or without radiation therapy (RT), or RT alone, for completely resected stage I to stage IV uterine carcinosarcoma with rhabdomyosarcoma differentiation were included.ResultsOf 53 patients, International Federation of Gynecology and Obstetrics stage distribution was as follows: I, 13 (24.5%); II, 8 (15.1%); III, 13 (24.5%); and IV, 19 (35.9%). Forty-one (77.4%) of 53 patients received adjuvant chemotherapy, and 34% of the patients who received chemotherapy also received pelvic RT or intravaginal brachytherapy (IVRT). Twelve (22.6%) of the 53 patients received only pelvic RT with/without IVRT. Paclitaxel-carboplatin was the most commonly used adjuvant chemotherapy treatment. The median PFS for the entire cohort was 13.4 months (95% confidence interval [CI], 10.5–17.0). The median OS for the entire cohort was 23.0 months (95% CI, 16.9–34.3). The median PFS periods by stage were 15.9 months for stages I/II versus 11.2 months for stages III/IV (P= 0.012). Median OS was not reached in the early-stage cohort. The median OS for the late-stage cohort was 20.9 months (P= 0.004). The median PFS periods by treatment were 10.4 months for pelvic RT with/without IVRT group versus 13.1 months for chemotherapy with/without pelvic RT with/without IVRT group (P= 0.498). The median OS periods by treatment were 23.6 months for chemotherapy with/without pelvic RT with/without IVRT group versus 16.9 months for pelvic RT with/without IVRT group (P= 0.501).ConclusionThe results suggest that chemotherapy alone or in combination with RT is associated with longer PFS and OS compared to RT alone. Only the stage of disease significantly affected PFS and OS.

scholarly journals Diagnostic AI Modeling and Pseudo Time Series Profiling of AD and PD Based on Individualized Serum Proteome Data

2021 ◽  
Vol 1 ◽  
Author(s):  
Jianhu Zhang ◽  
Xiuli Zhang ◽  
Yuan Sh ◽  
Benliang Liu ◽  
Zhiyuan Hu
Keyword(s):  
Machine Learning ◽  
Neurodegenerative Diseases ◽  
Early Stage ◽  
Group Versus ◽  
Blood Protein ◽  
Diagnostic Model ◽  
Feature Engineering ◽  
Ann Model ◽  
Test Set ◽  
Upstream Regulators

Background: Parkinson’s disease (PD), Alzheimer’s disease (AD) are common neurodegenerative disease, while mild cognitive impairment (MCI) may be happened in the early stage of AD or PD. Blood biomarkers are considered to be less invasive, less cost and more convenient, and there is tremendous potential for the diagnosis and prediction of neurodegenerative diseases. As a recently mentioned field, artificial intelligence (AI) is often applied in biology and shows excellent results. In this article, we use AI to model PD, AD, MCI data and analyze the possible connections between them.Method: Human blood protein microarray profiles including 156 CT, 50 MCI, 132 PD, 50 AD samples are collected from Gene Expression Omnibus (GEO). First, we used bioinformatics methods and feature engineering in machine learning to screen important features, constructed artificial neural network (ANN) classifier models based on these features to distinguish samples, and evaluated the model’s performance with classification accuracy and Area Under Curve (AUC). Second, we used Ingenuity Pathway Analysis (IPA) methods to analyse the pathways and functions in early stage and late stage samples of different diseases, and potential targets for drug intervention by predicting upstream regulators.Result: We used different classifier to construct the model and finally found that ANN model would outperform the traditional machine learning model. In summary, three different classifiers were constructed to be used in different application scenarios, First, we incorporated 6 indicators, including EPHA2, MRPL19, SGK2, to build a diagnostic model for AD with a test set accuracy of up to 98.07%. Secondly, incorporated 15 indicators such as ERO1LB, FAM73B, IL1RN to build a diagnostic model for PD, with a test set accuracy of 97.05%. Then, 15 indicators such as XG, FGFR3 and CDC37 were incorporated to establish a four-category diagnostic model for both AD and PD, with a test set accuracy of 98.71%. All classifier models have an auc value greater than 0.95. Then, we verified that the constructed feature engineering filtered out fewer important features but contained more information, which helped to build a better model. In addition, by classifying the disease types more carefully into early and late stages of AD, MCI, and PD, respectively, we found that early PD may occur earlier than early MCI. Finally, there are 24 proteins that are both differentially expressed proteins and upstream regulators in the disease group versus the normal group, and these proteins may serve as potential therapeutic targets and targets for subsequent studies.Conclusion: The feature engineering we build allows better extraction of information while reducing the number of features, which may help in subsequent applications. Building a classifier based on blood protein profiles using deep learning methods can achieve better classification performance, and it can help us to diagnose the disease early. Overall, it is important for us to study neurodegenerative diseases from both diagnostic and interventional aspects.

Carbon allocation in early successional tree species at elevated air humidity and different soil nitrogen sources

2021 ◽  
Author(s):  
Marili Sell ◽  
Ivika Ostonen ◽  
Gristin Rohula-Okunev ◽  
Azadeh Rezapour ◽  
Priit Kupper
Keyword(s):  
Biomass Allocation ◽  
Tree Species ◽  
Root Respiration ◽  
Fine Root ◽  
Silver Birch ◽  
Organic Carbon Content ◽  
Climate Change Scenarios ◽  
Air Humidity ◽  
Species Specific ◽  
Exudation Rate

&lt;p&gt;Global climate change scenarios predict increasing air temperature, enhanced precipitation and air humidity for Northern latitudes. We&amp;#8239;investigated the effects of elevated air relative humidity (RH) and different inorganic nitrogen&amp;#8239;sources&amp;#8239;(NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt;, NH&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;+&lt;/sup&gt;) on above- and belowground traits in different tree species, with particular emphasis on rhizodeposition rates. Silver birch, hybrid aspen and Scots pine saplings were grown in PERCIVAL growth chambers with stabile temperature, light intensity and two different air humidity conditions: moderate (mRH, 65% at day and 80% at night) and elevated (eRH, 80% at day and night). The collection of fine root exudates was conducted by a culture-based cuvette method and total organic carbon content was determined by Vario TOC analyser. Fine root respiration was measured with an infra-red gas analyser CIRAS 2.&amp;#8239;&amp;#160;&lt;/p&gt;&lt;p&gt;We analysed species-specific biomass allocation, water and rhizodeposition fluxes, foliar and fine root traits in response to changing environmental conditions. The&amp;#8239;eRH&amp;#8239;significantly decreased the transpiration flux in all species. In birch the transpiration flux was also affected by the nitrogen source. The average carbon exudation rate for aspen, birch and pine varied from 2 to 3 &amp;#8239;&amp;#956;g&amp;#8239;C g&lt;sup&gt;-1&lt;/sup&gt;&amp;#8239;day&amp;#8239;&lt;sup&gt;-1&lt;/sup&gt;. The exudation rates for deciduous tree species tended to increase at&amp;#8239;eRH, while conversely decreased for coniferous trees (p=0.045), coinciding with the changes in biomass allocation.&amp;#8239;C flux released by fine root respiration varied more than the fine root exudation, whereas the highest root respiration was found in silver birch and lowest in aspen. At eRH the above and belowground&amp;#8239;biomass ratio in aspen increased, at the expense of decreased root biomass and root respiration.&amp;#8239;&amp;#160;&lt;/p&gt;&lt;p&gt;Moreover,&amp;#8239;eRH&amp;#8239;significantly affected fine root morphology, whereas the response of specific root area was reverse for deciduous and coniferous tree species. However, fine roots with lower root tissue density had higher C exudation rate. Our findings underline the importance of considering species-specific differences by&amp;#8239;elucidating tree&amp;#8217;s&amp;#8239;acclimation&amp;#8239;to environmental factors and their&amp;#8239;interactions.&amp;#8239;&amp;#8239;&amp;#160;&lt;/p&gt;

scholarly journals Towards Conservation of Genetic Variation of Tropical Tree Species With Differing Successional Status: The Case of Mansonia altissima A. Chev and Triplochiton scleroxylon K. Schum

2019 ◽  
Vol 12 ◽  
pp. 194008291986426
Author(s):  
Akin Akinnagbe ◽  
Oliver Gailing ◽  
Reiner Finkeldey ◽  
Amadu Lawal
Keyword(s):  
Genetic Diversity ◽  
Human Impact ◽  
Tree Species ◽  
Human Impacts ◽  
Genetic Erosion ◽  
Primary Forest ◽  
Timber Species ◽  
Pioneer Species ◽  
Forest Patch ◽  
Successional Status

Two important West African timber tree species with differing successional status, Mansonia altissima A. Chev and Triplochiton scleroxylon K. Schum were investigated in this study. Triplochiton scleroxylon is a pioneer species found in open forests, whereas Mansonia altissima is a nonpioneer light-demanding tree species occurring in closed forests. Amplified fragment length polymorphism markers were used to compare the genetic diversities of these two timber species in stands with different degrees of human impact (isolated forest patch, logged forest, farmland, plantation, and primary forest). Contrasting effects of human impact on genetic diversity were detected for these two timber species. The results suggested severe effects of human impact on the genetic diversity of Mansonia altissima, a nonpioneer species. However, no adverse effect was recorded in Triplochiton scleroxylon, a pioneer species. These findings indicate that nonpioneer tree species could be more prone to genetic erosion than pioneer tree species as a result of adverse human impacts. Therefore, conservation of genetic diversity in both pioneer and nonpioneer tree species populations would likely necessitate different measures.

scholarly journals Do polyembryonic seeds of Carapa surinamensis (Meliaceae) have advantages for seedling development?

2019 ◽  
Vol 49 (2) ◽  
pp. 97-104 ◽  
Author(s):  
Débora Najara de SOUZA FERREIRA ◽  
José Luís Campana CAMARGO ◽  
Isolde Dorothea Kossmann FERRAZ
Keyword(s):  
Tree Species ◽  
Shoot Development ◽  
Seedling Development ◽  
External Factors ◽  
Initial Development ◽  
Advantages And Disadvantages ◽  
Single Seed ◽  
Seed Reserves

ABSTRACT Polyembryony is the differentiation and development of multiple embryos in a single seed. This characteristic can provide advantages, as more than one embryo is produced with the same amount of resources, and the probability of establishment of at least one seedling increases. However, sibling seedlings may also increase competition, affecting development and survival. In the present study, the possible advantages and disadvantages of polyembryony were analyzed in the initial establishment of seedlings of Carapa surinamensis (Meliaceae), a tree species that produces monoembryonic or polyembryonic seeds. In this regard, the development of single seedlings was compared with a pair of seedlings emerging from polyembryonic seeds. We compared the development of seedlings attached to or detached from each other and to the seed resources. We observed two levels of competition: (a) for the seed reserves during germination and initial development, as multiple embryos of C. surinamensis share the same reserves, and (b) for external factors, mostly space for root and shoot development, and also for light. Reducing the competition for external factors by separating the siblings was not enough to reduce the effects of competition for seed reserves in the first six months of development. Nevertheless, viable seedlings were produced in all treatments. Thus, depending on sprout management in the nursery, the number of seedlings per seed can be significantly increased by detaching the seedlings, or more vigorous seedlings can be obtained when only one seedling is maintained.

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