scholarly journals Influence of Slope Direction on the Soil Seed Bank and Seedling Regeneration of Castanopsis hystrix Seed Rain

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 500
Author(s):  
Zong Zhao ◽  
Yong Liu ◽  
Hongyan Jia ◽  
Wensheng Sun ◽  
Angang Ming ◽  
...  
Keyword(s):  
Seed Bank ◽  
Temporal Dynamics ◽  
Soil Seed Bank ◽  
Soil Layer ◽  
Seed Rain ◽  
Seed Vigor ◽  
Study Results ◽  
The Impact ◽  
Mature Seeds

Objective: To investigate the impact of different slope directions on the quantity and quality of the soil seed bank and seedling germination process of Castanopsis hystrix plantations. Method: Fixed sample plots in forest stands of Castanopsis hystrix were established on different slope directions (sunny slope, semi-sunny slope, semi-shady slope, and shady slope). The characteristics of the forest stand were investigated, and per-wood scaling was carried out. The temporal dynamics of the seed rain and seed bank were quantified using seed rain collectors and by collecting soil samples from different depths. The quantity and quality of the seeds were determined, and the vigor of mature seeds was measured throughout the study. Results: (1) The diffusion of Castanopsis hystrix seed rain started in mid-September, reached its peak from late October to early November, and ended in mid-December. (2) The dissemination process, occurrence time, and composition of the seed rain varied between the different slope directions. The seed rain intensity on the semi-sunny slope was the highest (572.75 ± 9.50 grains∙m−2), followed by the sunny slope (515.60 ± 10.28 grains∙m−2), the semi-shady slope (382.13 ± 12.11 grains∙m−2), and finally the shady slope (208.00 ± 11.35 grains∙m−2). The seed rain on the sunny slope diffused earliest and lasted the longest, while the seed rain on the shady slope diffused latest and lasted the shortest time. Seed vigor and the proportion of mature seeds within the seed rain were greatest on the semi-sunny slope, followed by the sunny slope, semi-shady slope, and the shady slope. (3) From the end of the seed rain to August of the following year, the amount of total reserves of the soil seed banks was highest on the semi-sunny slope, followed by the sunny slope then the semi-shady slope, and it was the lowest on the shady slope. The amount of mature, immature, gnawed seeds and seed vigor of the soil seed bank in various slope directions showed a decreasing trend with time. The seeds of the seed bank in all slope directions were mainly distributed in the litter layer, followed by the 0–2 cm humus layer, and only a few seeds were present in the 2–5 cm soil layer. (4) The seedling density of Castanopsis hystrix differed significantly on the different slope directions. The semi-sunny slope had the most seedlings, followed by the sunny slope, semi-shady slope, and the shady slope. Conclusions: The environmental conditions of the semi-sunny slope were found to be most suitable for the seed germination and seedling growth of Castanopsis hystrix, and more conducive to the regeneration and restoration of its population.

scholarly journals Size-Dependent Patterns of Seed Rain in Gaps in Temperate Secondary Forests, Northeast China

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 123 ◽  
Author(s):  
Qiaoling Yan ◽  
Qun Gang ◽  
Jiaojun Zhu
Keyword(s):  
Seed Bank ◽  
Tree Species ◽  
Natural Regeneration ◽  
Temporal Dynamics ◽  
Soil Seed Bank ◽  
Seed Rain ◽  
Spatiotemporal Pattern ◽  
Small Scale ◽  
Secondary Forests ◽  
Gap Size

Secondary forests have become the major forest type worldwide, and are experiencing various disturbances and exhibiting obvious vegetation degradation (e.g., reduced biodiversity and decreased productivity) compared with primary forests. Forest gap is a common small-scale disturbance in secondary forests. Promoting natural regeneration under gap disturbance is an important approach to recover biodiversity and ecosystem services for temperate secondary forests. The gap size is the crucial characteristic controlling natural regeneration of many tree species. However, little is known about the spatiotemporal pattern of seed rain for gravity-dispersed and wind-dispersed tree species in gaps of varying sizes. The objectives of this study were to determine how seed rain of dominant tree species depend on gap size, and consequently, to explore some gap-based silviculture solutions for restoring secondary forests from the view of seed dispersal. The spatial distribution of seed rain in gaps with three sizes (large gaps of 250–350 m2, medium gaps of 150–250 m2, and small gaps of < 150 m2), the temporal dynamics of seed rain over three years, and the relationship between seed rain and soil seed banks were explored in temperate secondary forests. The results showed that more than 90% of the seeds in seed rain were wind-dispersed, and their seed rain density and the contribution of seed rain to soil seed bank in medium gaps reached the highest (p = 0.03). The results suggest that establishing medium-sized gaps (i.e., gap size with 150–250 m2) in the secondary forests is more favorable for improving the natural regeneration potential (arrival of seeds and forming soil seed bank) of gap-dependent and wind-dispersed species (e.g., Acer mono) in gaps.

scholarly journals Weed Flora and Soil Seed Bank Composition as Affected by Tillage System in Three-Year Crop Rotation

Agriculture ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 186 ◽  
Author(s):  
Beata Feledyn-Szewczyk ◽  
Janusz Smagacz ◽  
Cezary A. Kwiatkowski ◽  
Elżbieta Harasim ◽  
Andrzej Woźniak
Keyword(s):  
Winter Wheat ◽  
Crop Rotation ◽  
Seed Bank ◽  
Soil Seed Bank ◽  
Soil Layer ◽  
Agricultural Science ◽  
No Till ◽  
Weed Flora ◽  
Weed Seeds ◽  
Direct Sowing

In recent years, there has been an increasing interest around agricultural science and practice in conservation tillage systems that are compatible with sustainable agriculture. The aim of this study was to assess the qualitative and quantitative changes in weed flora and soil seed bank under reduced tillage and no-till (direct sowing) in comparison with traditional ploughing. In the crop rotation: pea/rape—winter wheat—winter wheat the number and dry weight of weeds increased with the simplification of tillage. The seed bank was the largest under direct sowing and about three times smaller in traditional ploughing. Under direct sowing, most weed seeds were accumulated in the top soil layer 0–5 cm, while in the ploughing system most weed seeds occurred in deeper layers: 5–10 and 10–20 cm. In the reduced and no-till systems, a greater percentage of perennial and invasive species, such as Conyza canadensis L., was observed. The results show that it is possible to maintain weed infestation in the no-till system at a level that does not significantly affect winter wheat yield and does not pose a threat of perennial and invasive weeds when effective herbicide protection is applied.

Soil seed bank and vegetation dynamics in Sahelian fallows; the impact of past cropping and current grazing treatments

2004 ◽  
Vol 20 (6) ◽  
pp. 683-691 ◽  
Author(s):  
Bruno Hérault ◽  
Pierre Hiernaux
Keyword(s):  
Seed Bank ◽  
Management Practices ◽  
Soil Seed Bank ◽  
Residual Effects ◽  
Ex Situ ◽  
Phosphorus Fertilizer ◽  
Wet Season ◽  
Seed Extraction ◽  
The Impact

The soil seed bank in a 5-y-old Sahelian fallow was studied through seed extraction and compared with germinations recorded either in controlled conditions, ex situ in a glasshouse, or in the field. The influence of phosphorus fertilizer and mulch application during the preceding crop period, and that of seasonal grazing regimes applied the last 2 y of fallowing, were assessed on the composition of the seed stock. Ctenium elegans, Fimbristylis hispidula, Merremia pinnata and Phyllanthus pentandrus accounted together for 75% of extracted seeds, 72% of ex situ, and 62% of in situ seedlings. Mulch treatment was correlated with the first axis of the canonical correspondence analyses performed on the seedling datasets. Mulch and phosphorus fertilizer treatments held similar responses, as they both favoured the seed bank of erect dicotyledons such as P. pentandrus and Cassia mimosoides. On the whole, the effects of grazing remained modest compared with the residual effects of past crop management practices. However, seedling densities increased as a result of dry-season grazing, while the soil seed bank decreased with wet-season grazing. Grazing also reduced the spatial heterogeneity of the seed bank rather than the overall number of species.

scholarly journals The Impact of Accounting on Environmental Costs to Improve the Quality of Accounting Information in the Jordanian Industrial Companies

2017 ◽  
Vol 12 (6) ◽  
pp. 104
Author(s):  
Atalla M. Alqotaish ◽  
Adel M. Qatawneh
Keyword(s):  
Accounting Information ◽  
Environmental Cost ◽  
Environmental Costs ◽  
Statistical Relationship ◽  
Industrial Companies ◽  
Study Results ◽  
Quality Of Accounting Information ◽  
Collective Performance ◽  
The Impact

The Impact of Accounting of Environmental Costs to Improve the Quality of Accounting Information in the Jordanian Industrial Companies is a study aimed to explore the importance of accounting on environmental cost in the improve of the quality of accounting information. Data were collected through from the Jordanian companies and a questionnaire distributed among the workers of offices and departments of accounting in the industrial companies listed in Jordan stock market. The study came up with the following findings: The study has shown that there exists a significant statistical relationship between the size of environmentally-related accounting disclosure of information for publicly owned companies and the adequacy of financial listing of such companies. The study has shown that there exists a significant statistical relationship between Investors decisions and the information provided by the collective performance disclosure. As per the study results, we recommend the following: The necessity of accountants' obligation towards environmentally-related auditing information provided with the financial reports, and the necessity of emphasizing on information importance as provided by the environmentally-related collective performance.

scholarly journals The Impact of Fire on the Soil Seed Bank and Regeneration of Harenna Forest, Southeastern Ethiopia

2004 ◽  
Vol 24 (4) ◽  
pp. 354-361 ◽  
Author(s):  
Getachew Tesfaye ◽  
Demel Teketay ◽  
Yoseph Assefa ◽  
Masresha Fetene
Keyword(s):  
Seed Bank ◽  
Soil Seed Bank ◽  
The Impact

KINEMATICS FEATURES OF HAMMER PERFORATED TILLAGE ROLL

2020 ◽  
pp. 13-19
Author(s):  
I. А. Sharonov ◽  
◽  
Yu. М. Isaev ◽  
V. I. Kurdyumov ◽  
◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Soil Layer ◽  
Point Of View ◽  
Lagrange Equations ◽  
Middle Volga Region ◽  
Perforated Cylinder ◽  
Winter Crops ◽  
Combined Impact ◽  
The Impact

The task of improving the quality of agricultural tools by improving the technological processes of their functioning, taking into account the kinematic features of the combined impact of working elements of tools on the soil environment is important from a scientific and technical point of view. To form the required structure and density of the soil layer at the depth of sowing, a hammer perforated tillage roller (HPTR) has been developed. The study aim is to improve the quality of post-sowing compaction and structuring of the soil layer in the seed location zone based on the development of an innovative design of HPTR that combines different effects on the treated environment. The object of research is the kinematic mode of operation of the HPTR, equipped with cylindrical hammers installed at the ends of the rod, which, in turn, are radially and pivotally installed on the axis of the gunFeature of offered HPTR is the excitation of hammer vibrations, which changes the kinematic parameters of the tillage tool as a whole. Lagrange equations of the second kind are used to describe the process of HPTR operation, which is represented as a system of material objects with several degrees of freedom. The conducted studies revealed the periodic nature of changes in the strength of the impact of HPTR on the soil. The obtained equations allow us to determine the features of the HPTR movement at different masses of a hollow perforated cylinder and cylindrical hammers. This is of great importance for increasing the efficiency of soil bolster destruction and creating the soil structure recommended for winter crops sown in the Middle Volga region.

Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

2020 ◽  
Vol 13 (3) ◽  
pp. 256-265 ◽  
Author(s):  
José Djalma de Souza ◽  
Bruno Ayron de Souza Aguiar ◽  
Danielle Melo dos Santos ◽  
Vanessa Kelly Rodrigues de Araujo ◽  
Júlia Arruda Simões ◽  
...  
Keyword(s):  
Seed Bank ◽  
Linear Models ◽  
Temporal Dynamics ◽  
Soil Seed Bank ◽  
Seed Banks ◽  
Dry Forest ◽  
Herbaceous Species ◽  
Physical Dormancy ◽  
Soil Seed Banks ◽  
Interspecific Differences

Abstract Aims In dry tropical forests, herbaceous species may have dormancy mechanisms and form persistent and transient seed banks in the soil. Evolutionarily acquired, these mechanisms are efficient for the establishment and survival of these herbs, especially in forests with unpredictable climates, such as the Caatinga. Thus, our objective was to verify whether the studied herbaceous species adopt the physical dormancy mechanism and how these natural barriers are overcome, to understand the temporal dynamics existing in the soil seed bank from a Brazilian dry tropical forest. Methods Seeds of five native herbaceous species from the Caatinga forests were selected and submitted to pre-germinative treatments for verifying the presence of physical dormancy. We collected soil samples in the rainy and dry seasons for four consecutive years and monitored the emergence of the selected herbaceous in the greenhouse. We verified the differences in germination and seed bank emergence in the soil by generalized linear models. Important Findings The presence and absence of physical dormancy were observed in seeds from Caatinga herbaceous species. We found intraspecific and interspecific differences in the herbaceous emergence from soil seed banks between years and climatic seasons. In perennial herbs, consecutive lack of emergence between seasons and years was frequent, which suggests a direct relationship with the mechanism of physical dormancy and the environmental conditions necessary to overcome integument barriers. In these species, seed dimorphism and dormancy may confer additional advantages to their survival. Moreover, presenting intermediate levels of physical dormancy in an annual species may be an evolutionary adjustment to rainfall unpredictability. In contrast, we found that the annual herb without dormancy is more sensitive to seasonal and interannual climate changes, as evidenced by the increase and significant reduction of its emergence in the soil seed bank. These differences acquired evolutionarily are advantageous for the establishment of herbaceous populations, mainly in semiarid regions with an unpredictable climate.

Early palliative care in haematological patients: a systematic literature review

2020 ◽  
Vol 10 (4) ◽  
pp. 395-403
Author(s):  
Silvia Tanzi ◽  
Francesco Venturelli ◽  
Stefano Luminari ◽  
Franco Domenico Merlo ◽  
Luca Braglia ◽  
...  
Keyword(s):  
Palliative Care ◽  
Comparative Studies ◽  
English Language ◽  
Meta Analysis ◽  
Early Palliative Care ◽  
Study Results ◽  
Registration Number ◽  
Integrated Or ◽  
The Impact

BackgroundEarly palliative care together with standard haematological care for advanced patients is needed worldwide. Little is known about its effect. The aim of the review is to synthesise the evidence on the impact of early palliative care on haematologic cancer patients’ quality of life and resource use.Patients and methodsA systematic review was conducted. The search terms were early palliative care or simultaneous or integrated or concurrent care and haematological or oncohaematological patients. The following databases were searched: PubMed, Embase, Cochrane, CINHAL and Scopus. Additional studies were identified through cross-checking the reference articles. Studies were in the English language, with no restriction for years. Two researchers independently reviewed the titles and abstracts, and one author assessed full articles for eligibility.ResultsA total of 296 studies titles were reviewed. Eight articles were included in the synthesis of the results, two controlled studies provided data on the comparative efficacy of PC interventions, and six one-arm studies were included. Since data pooling and meta-analysis were not possible, only a narrative synthesis of the study results was performed. The quality of the two included comparative studies was low overall. The quality of the six non-comparative studies was high overall, without the possibility of linking the observed results to the implemented interventions.ConclusionsStudies on early palliative care and patients with haematological cancer are scarce and have not been prospectively designed. More research on the specific population target, type and timing of palliative care intervention and standardisation of collected outcomes is required.PROSPERO registration numberCRD42020141322.

scholarly journals Impact of malocclusion on the quality of life of children aged 8 to 10 years

2018 ◽  
Vol 23 (2) ◽  
pp. 46-53 ◽  
Author(s):  
Sônia Rodrigues Dutra ◽  
Henrique Pretti ◽  
Milene Torres Martins ◽  
Cristiane Baccin Bendo ◽  
Miriam Pimenta Vale
Keyword(s):  
Quality Of Life ◽  
Negative Impact ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Significance Level ◽  
Normal Occlusion ◽  
Study Results ◽  
Belo Horizonte ◽  
The Impact

ABSTRACT Objective: The aim of the present cross-sectional study was to assess the impact of malocclusion on the quality of life of children aged 8 to 10 years attending public elementary schools in Belo Horizonte, State of Minas Gerais, Brazil. Methods: The Brazilian version of the Child Perceptions Questionnaire 8-10 (CPQ8-10) was used to evaluate oral health-related quality of life. The children were examined for the diagnosis of malocclusion using the Dental Aesthetic Index (DAI). The data were analyzed by bivariate and multivariate descriptive statistics using Poisson regression at a 5% significance level. A total of 270 children participated in the study. Results: Children with normal occlusion or mild malocclusion (DAI ≤ 25) were 56% less likely (95%CI: 0.258-0.758; p= 0.003) to have their quality of life affected compared with children diagnosed with extremely severe malocclusion (DAI ≥ 36). Children with a maxillary anterior overjet ≥ 3 mm had higher CPQ8-10 mean scores (19.4; SD = 17.1) than those with an overjet < 3 mm (13.6; SD = 11.7; p= 0.038). Conclusions: Extremely severe malocclusion and pronounced maxillary anterior overjet were associated with a negative impact on quality of life.

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