scholarly journals Ecological stoichiometric characteristics and influencing factors of carbon, nitrogen, and phosphorus in the leaves of Sophora alopecuroides L. in the Yili River Valley, Xinjiang

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11701
Author(s):  
Yulu Zhang ◽  
Dong Cui ◽  
Yuhai Yang ◽  
Haijun Liu ◽  
Haijun Yang ◽  
...  
Keyword(s):  
Influencing Factors ◽  
Ammonium Nitrogen ◽  
River Valley ◽  
Perennial Herb ◽  
Dominant Factor ◽  
Nitrogen And Phosphorus ◽  
Soil C ◽  
Factors Affecting ◽  
Sophora Alopecuroides ◽  
P Content

Background Sophora alopecuroides L. (S. alopecuroides L.) is a perennial herb widely distributed throughout Xinjiang, China. It is characterized by its rapid diffusion ability. Methods To reveal the ecological mechanism of the rapid spread of S. alopecuroides, and to elucidate the ecological stoichiometric characteristics of C, N, and P (and the influencing factors) in the leaves of S. alopecuroides, leaves were sampled from four habitats—forest, roadside, farmland, and desert—across the Yili River Valley. The variation rules of the ecological stoichiometric characteristics of C, N, and P in the leaves of S. alopecuroides were analyzed. Correlations between the ecological stoichiometric characteristics of leaves and environmental factors were examined using redundancy analysis (RDA). Results (1) The C, N, and P contents of S. alopecuroides leaves were 391.30–533.10 g/kg, 8.90–43.14 g/kg, and 0.71–2.04 g/kg, respectively, and the C/N, C/P, and N/P ratios were 10.34–4.94, 209.05–698.73, and 10.78–31.43 respectively. (2) The C content and C/P ratio of S. alopecuroides leaves were the highest in the desert habitat, leaf N content and N/P ratio were the highest in the forest habitat, leaf P content was the highest in the farmland habitat, and the leaf C/N ratio was the highest in the roadside habitat. (3) RDA showed that available potassium (AK) and pH were the main factors affecting the ecological stoichiometric characteristics of S. alopecuroides leaves in Yili Valley (p ≤ 0.05), and these factors were positively correlated with C, N, P, and N/P, and negatively correlated with C/P and C/N. AK was the dominant factor that affected the P content of S. alopecuroides leaves, and appropriate reduction of K fertilizer would be conducive to restraining the spread of S. alopecuroides. Soil C, N, P, and K content, soil organic matter (OM), nitrate nitrogen (NO3−-N), ammonium nitrogen (NH4+-N), and AK had no significant effect on the ecological stoichiometric characteristics of leaves (p > 0.05).

scholarly journals Aphid–Plant–Phytovirus Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread

Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 502
Author(s):  
Junior Corneille Fingu-Mabola ◽  
Frédéric Francis
Keyword(s):  
Influencing Factors ◽  
Virus Transmission ◽  
Physical Factors ◽  
Factors Affecting ◽  
Vector Borne Diseases ◽  
Vector Behaviour ◽  
Crop Fields ◽  
Host Seeking ◽  
The Impact ◽  
Vector Efficiency

Aphids are responsible for the spread of more than half of the known phytovirus species. Virus transmission within the plant–aphid–phytovirus pathosystem depends on vector mobility which allows the aphid to reach its host plant and on vector efficiency in terms of ability to transmit phytoviruses. However, several other factors can influence the phytoviruses transmission process and have significant epidemiological consequences. In this review, we aimed to analyse the aphid behaviours and influencing factors affecting phytovirus spread. We discussed the impact of vector host-seeking and dispersal behaviours mostly involved in aphid-born phytovirus spread but also the effect of feeding behaviours and life history traits involved in plant–aphid–phytovirus relationships on vector performances. We also noted that these behaviours are influenced by factors inherent to the interactions between pathosystem components (mode of transmission of phytoviruses, vector efficiency, plant resistance, …) and several biological, biochemical, chemical or physical factors related to the environment of these pathosystem components, most of them being manipulated as means to control vector-borne diseases in the crop fields.

scholarly journals The role of serum β-trophin and endostatin in patients with polycystic ovary syndrome: Are they correlated?

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wei Gong ◽  
Aikmu Bilixzi ◽  
Xinmei Wang ◽  
Yanli Lu ◽  
Li Wan ◽  
...  
Keyword(s):  
Polycystic Ovary Syndrome ◽  
Influencing Factors ◽  
Polycystic Ovary ◽  
Pearson Correlation ◽  
Healthy Controls ◽  
Newly Diagnosed ◽  
Ovary Syndrome ◽  
Factors Affecting ◽  
Main Factors

Abstract Background It’s necessary to investigate the serum β-trophin and endostatin (ES) level and its influencing factors in patients with newly diagnosed polycystic ovary syndrome (PCOS). Methods Newly diagnosed PCOS patients treated in our hospital were selected, and healthy women who took physical examination during the same period as healthy controls. We detected and compared the related serum indicators between two groups, Pearson correlation were conducted to identify the factors associated with β-trophin and ES, and the influencing factors of β-trophin and ES were analyzed by logistic regression. Results A total of 62 PCOS patients and 65 healthy controls were included. The BMI, WHI, LH, FSH, TT, FAI, FBG, FINS, HOMA-IR, TC, TG, LDL, ES in PCOS patients were significantly higher than that of healthy controls, while the SHBG and HDL in PCOS patients were significantly lower than that of healthy controls (all p < 0.05). β-trophin was closely associated with BMI (r = 0.427), WHR (r = 0.504), FBG (r = 0.385), TG (r = 0.405) and LDL (r = 0.302, all p < 0.05), and ES was closely associated with BMI (r = 0.358), WHR (r = 0.421), FBG (r = 0.343), TC (r = 0.319), TG (r = 0.404, all p < 0.05). TG, BMI, WHR and FBG were the main factors affecting the serum β-trophin levels (all p < 0.05). FBG, TC and BMI were the main factors affecting the serum ES levels (all p < 0.05). The TG, β-trophin, ES level in PCOS patients with insulin resistance (IR) were significantly higher than that of those without IR (all p < 0.05). Conclusion Increased β-trophin is closely associated with increased ES in patients with PCOS, which may be the useful indicators for the management of PCOS.

scholarly journals Grey Relational Grade Based Quantitative Analysis of the Factors Influencing the Load Characteristics of A Power Grid

2018 ◽  
Vol 53 ◽  
pp. 01012 ◽  
Author(s):  
Wei Pan ◽  
Caijia Lei ◽  
Wei Jia ◽  
Hui Gao ◽  
Binghua Fang
Keyword(s):  
Quantitative Analysis ◽  
Influencing Factors ◽  
Power Grid ◽  
Grey System Theory ◽  
Grey System ◽  
Factors Affecting ◽  
Grey Relational Grade ◽  
Load Characteristics ◽  
Grey Relational ◽  
Main Factor

Regarding analysis of load characteristics of a power grid, there are multiple factors that influence the variation of load characteristics. Among these factors, the influence of different ones on the change of load characteristic is somewhat different, thus the degree of influence of various factors needs to be quantified to distinguish the main and minor factors of load characteristics. Based on this, the grey relational analysis in the grey system theory is employed as the basis of mathematical model in this paper. Firstly, the main factors affecting the load characteristics of a power grid are analysed. Then, the principle of quantitative analysis of the influencing factors by using grey relational grade is introduced. Lastly, the load of Guangzhou power grid is selected as the research object, thereby the main factor of temperature affecting the load characteristics is quantitatively analysed, such that the correlation between temperature and load is established. In this paper, by investigating the influencing factors and the degree of influence of load characteristics, the law of load characteristics changes can be effectively revealed, which is of great significance for power system planning and dispatching operation.

Investigation on Polymer Adsorption and Retention in a Polymer Flooded Reservoir

2013 ◽  
Vol 734-737 ◽  
pp. 1200-1203
Author(s):  
Shu Qiang Liu ◽  
Ji Cheng Zhang ◽  
Jin Cheng Xu
Keyword(s):  
Polymer Solution ◽  
Influencing Factors ◽  
Polymer Adsorption ◽  
Solution Concentration ◽  
Injection Rate ◽  
The Other ◽  
Injection Time ◽  
Factors Affecting ◽  
Dynamic Factors ◽  
Polymer Retention

During polymer flooding, certain amount of polymer would be lost. Polymer retention causes sweep volume expanding on one side, it also causes polymer loss on the other. Therefore, it is a very important topic to study the influencing factors of polymer retention. There are many factors affecting polymer retention process. This paper mainly studied the influence from dynamic factors such as polymer solution concentration, injection rate, injection time, injected pv number. This paper investigated the influence of these factors on polymer retention process, and optimized these factors to minimize polymer loss in reservoir.

What is access to radiation therapy? A conceptual framework and review of influencing factors

2016 ◽  
Vol 40 (1) ◽  
pp. 11 ◽  
Author(s):  
Puma Sundaresan ◽  
Martin R. Stockler ◽  
Christopher G. Milross
Keyword(s):  
Radiation Therapy ◽  
Health Services ◽  
Conceptual Framework ◽  
Influencing Factors ◽  
International Literature ◽  
Access To Treatment ◽  
Access Methods ◽  
Factors Affecting ◽  
Detailed Review ◽  
Factors Influencing

Objectives Optimal radiation therapy (RT) utilisation rates (RURs) have been defined for various cancer indications through extensive work in Australia and overseas. These benchmarks remain unrealised. The gap between optimal RUR and actual RUR has been attributed to inadequacies in ‘RT access’. We aimed to develop a conceptual framework for the consideration of ‘RT access’ by examining the literature for existing constructs and translating it to the context of RT services. We further aimed to use this framework to identify and examine factors influencing ‘RT access’. Methods Existing models of health care access were reviewed and used to develop a multi-dimensional conceptual framework for ‘RT access’. A review of the literature was then conducted to identify factors reported to affect RT access and utilisation. The electronic databases searched, the host platform and date range of the databases searched were Ovid MEDLINE, 1946 to October 2014 and PsycINFOvia OvidSP,1806 to October 2014. Results The framework developed demonstrates that ‘RT access’ encompasses opportunity for RT as well as the translation of this opportunity to RT utilisation. Opportunity for RT includes availability, affordability, adequacy (quality) and acceptability of RT services. Several factors at the consumer, referrer and RT service levels affect the translation of this opportunity for RT to actual RT utilisation. Conclusion ‘Access’ is a term that is widely used in the context of health service related research, planning and political discussions. It is a multi-faceted concept with many descriptions. We propose a conceptual framework for the consideration of ‘RT access’ so that factors affecting RT access and utilisation may be identified and examined. Understanding these factors, and quantifying them where possible, will allow objective evaluation of their impact on RT utilisation and guide implementation of strategies to modify their effects. What is known about the topic? It is well documented that the use of RT in Australia is well below evidence-based benchmarks. The shortfall in the use of RT has been attributed to problems with access to treatment services. Although considerable attention has been directed (rightly) towards addressing infrastructure needs, access to RT is more than just supply of services. There is currently no specific framework for RT access to comprehensively consider and examine other factors influencing the use of RT. The existing international literature addresses some of the influencing factors. However, there is a need for a detailed review of all actual and potential influencers of RT utilisation. What does this paper add? This paper presents a conceptual framework for the specific consideration of access to RT. A detailed review of various factors affecting access and utilisation of RT has been performed using the aforementioned conceptual framework. To our knowledge this is the first such review and hence we are confident that it adds to the existing international literature on this subject. What are the implications for practitioners? The topic of improving consumers’ access to RT is of relevance locally, in Australia, as well as internationally. We feel that the RT access framework proposed herein will be of interest and use to those involved in health services research, delivery and policy, especially those involved with the planning and delivering of cancer services. In addition to compiling evidence on the subject, the review of factors influencing RT utilisation highlights and proposes areas for future translational and implementation research in the areas of health services and treatment-related decision making.

Simultaneous removal of nitrogen and phosphorus in a two-biofilter system

2000 ◽  
Vol 41 (12) ◽  
pp. 101-106 ◽  
Author(s):  
D. Pak ◽  
W. Chang
Keyword(s):  
Retention Time ◽  
Phosphorus Removal ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Aerobic Condition ◽  
Nitrogen Loading ◽  
Simultaneous Removal ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Factors Affecting

A two-biofilter system operated under alternate conditions of anaerobic/aerobic was tested to simultaneously remove nitrogen and phosphorus from sewage. The factors affecting simultaneous removal of nitrogen and phosphorus by the two-biofilter system were investigated. Those factors appeared to be influent COD/T-N and COD/T-P ratio, nitrogen loading rate and hydraulic retention time. Nitrite and nitrate produced in the biofilter in aerobic condition affected phosphorus removal by the two-biofilter system. The amount of biomass wasted during the backwash procedure also affected total nitrogen and phosphorus removal by the system.

scholarly journals Effect of Short-Term Low-Nitrogen Addition on Carbon, Nitrogen and Phosphorus of Vegetation-Soil in Alpine Meadow

2021 ◽  
Vol 18 (20) ◽  
pp. 10998
Author(s):  
Zhen’an Yang ◽  
Wei Zhan ◽  
Lin Jiang ◽  
Huai Chen
Keyword(s):  
Alpine Meadow ◽  
Nitrogen Addition ◽  
Ammonium Nitrogen ◽  
N Deposition ◽  
Total Carbon ◽  
N Addition ◽  
Short Term ◽  
Nitrogen And Phosphorus ◽  
Soil Rhizosphere ◽  
And Function

As one of the nitrogen (N) limitation ecosystems, alpine meadows have significant effects on their structure and function. However, research on the response and linkage of vegetation-soil to short-term low-level N deposition with rhizosphere processes is scant. We conducted a four level N addition (0, 20, 40, and 80 kg N ha−1 y−1) field experiment in an alpine meadow on the Qinghai-Tibetan Plateau (QTP) from July 2014 to August 2016. We analyzed the community characteristics, vegetation (shoots and roots), total carbon (TC), nutrients, soil (rhizosphere and bulk) properties, and the linkage between vegetation and soil under different N addition rates. Our results showed that (i) N addition significantly increased and decreased the concentration of soil nitrate nitrogen (NO3−-N) and ammonium nitrogen, and the soil pH, respectively; (ii) there were significant correlations between soil (rhizosphere and bulk) NO3−-N and total nitrogen (TN), and root TN, and there was no strong correlation between plant and soil TC, TN and total phosphorus, and their stoichiometry under different N addition rates. The results suggest that short-term low-N addition affected the plant community, vegetation, and soil TC, TN, TP, and their stoichiometry insignificantly, and that the correlation between plant and soil TC, TN, and TP, and their stoichiometry were insignificant.

scholarly journals Analisis Faktor Produksi Kalapa Sawit Rakyat Menurut Tipologi Lahan di Kabupaten Indragiri Hilir Provinsi Riau

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Heriyanto Heriyanto ◽  
Asrol Asrol ◽  
Detri Karya ◽  
Verry Yarda Ningsih
Keyword(s):  
Palm Oil ◽  
Oil Palm ◽  
Raw Materials ◽  
Least Square ◽  
Added Value ◽  
Dominant Factor ◽  
Factors Affecting ◽  
The Difference ◽  
Cultivation Techniques ◽  
Coastal Land

Heriyanto et al, 2018. Analysis of the Production Factors of the People's Palm Oil According to the Land Typology in Indragiri Hilir Regency, Riau Province. JLSO 7(1): Palm oil commodities are one of the plantation sub-sector commodities that increase the income of farmers and the community, provide processing industry raw materials that create added value. The land cultivated by independent oil palm farmers consists of land land, tidal peatlands, coastal peatlands and coastal land. The difference in typology of this land will contribute to different production. The research aimed to analyze the oil palm production and the dominant factor affecting oil palm production according to the typology of land in Indragiri Hilir Riau Province. The data were analyzed using descriptive statistics and built multiple regression models with the dummy variable method of Ordinary Least Square (OLS). The results of the study showed that the production of oil palm cultivation on land is the highest compared to the typology of tidal peatland, coastal peat and coastal land. The dominant factors affecting palm oil production in Indragiri Hilir Regency were the amount of fertilizer use, labor, age of plants, herbicides and dummy typology of land. In order to obtain optimal production, this study recommended doing oil palm farming in accordance with the correct cultivation techniques in accordance with the characteristics of land typology. Besides that the use of balanced fertilizer (elements of N, P, and K) in accordance with the recommended needed to be applied.

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