Distribution Of Environmental Factors Research Articles

Updates on Microgreens Grown under Artificial Lighting: Scientific Advances in the Last Two Decades

Microgreens have a high nutrient density and are beneficial to human health. Even though this class of vegetables have gaining increasing levels of attention in the last year, scientific research on the growth of microgreens in controlled environments under artificial lighting have not been thoroughly characterized. By describing the scientific outputs focused on the impacts of artificial illumination on microgreens, especially from the first two decades of the 21st century, it is therefore possible to detect advancements and research gaps in this research field. This review is divided in two parts: first, a general overview of the scientific production about microgreens; second, a systematic review of scientific studies exploring artificial lighting on the production of microgreens. The overview of scientific production on microgreens and artificial lighting across the Scopus, Web of Science, and Scielo databases, from 2000 to 2021, respectively, indicated three phases, as before 2011 no paper was found: phase 1 (2012 to 2014), six papers; phase 2 (2015 to 2018), fifteen papers; and phase 3 (2019 to 2021), forty-six papers, respectively. Mustard was the most evaluated crop under all production stages. With regard to the second part of this review, studies on artificial lighting with fluorescent lamps (high-pressure sodium light bulbs—HPS), from the supplementation to the replacement of HPS lighting with light emitting diode (LED) lamps, and plant responses with respect to light properties comprise the main works identified. Studies on the distribution of environmental factors under controlled microgreen cultivation present research gaps.

Phytoplankton communities and environmental variables as indicators of ecosystem productivity in a shallow tropical lake

The water quality and ecosystem productivity of a tropical lake in Ethiopia (Lake Arkiet) was evaluated using phytoplankton and environmental factors. This was to ascertaining the lake’s potential for various applications. Phytoplankton communities and some selected environmental variables were collected from two predefined sampling sites (open water and littoral) using a seasonal campaign between March to May (dry season) and June to August (wet season) in 2022. The analysis of the physicochemical characteristics of this study showed that the lake’s water was well-oxygenated (6.8–16.7 mg/L), warm (25.8–29.8 °C), turbid (154–317 NTU), had poor water transparency (4.3–16.1 cm), and was alkaline (pH = 7.29–11.31). The concentrations of inorganic nutrients (phosphate and nitrate) were notably high, ranging from 2.12–5.26 and 2.19–10.64 mg/L, respectively. A total of 34 phytoplankton taxa from four divisions were identified in Lake Arekit. Bacillariophyceae (18 taxa) and Chlorophyceae (10 taxa) were the major groups of phytoplankton which together represented the largest (82%) phytoplankton taxa. The total biovolume of phytoplankton in the lake was to be 384.15 mm3/L. Cyanobacteria contributed the largest (41%) phytoplankton biovolume followed by Bacillariophyta (32%). The highest biovolume (about 75%) was constituted in the Microcystis aeruginosa, Cylindrospermopsis raphidiopsis, Anabaena spiroides, Pediastrum duplex, Aulacoseira granulate, Navicula schroeteri, and Nitzschia palea. The distribution of environmental factors and phytoplankton communities showed greater seasonality. High phytoplankton biovolume was observed in the dry season at both sampling sites concurrently with high water transparency and low water temperature. Findings from this study revealed that Lake Arkeit was a moderately polluted but productive lacustrine ecosystem that can still support aquatic life, fish production, irrigation, and aquaculture. The primary source of the pollution is the entry of inorganic and organic wastes from a brewery and other water bottling industries nearby and around the lake, as well as possible excessive nutrient levels due to the lake’s geological background. It is advised that commercial factories stop producing or releasing waste in open spaces that are heavily washed and enter the lake via flooding and tributary rivers and streams. Additionally, the local government should work with the nearby communities to set up a buffer zone where people are prohibited from engaging in agricultural activities to protect and reduce pollution, which will help to preserve the lake’s water and ecosystem.

Vertical Fine-Scale Distribution of Calanus sinicus in the Yellow Sea Cold Water Mass During the Over-Summering Process

Calanus sinicus, a temperate copepod with a lethal temperature >27°C, is one of the key species in Chinese coastal marine ecosystems. The C. sinicus population increases in spring and declines in early summer annually due to increasing water temperature. Numerous C. sinicus individuals then congregate in the Yellow Sea Cold Water Mass (YSCWM) and remain under the thermocline from early summer to early autumn. Development and reproduction is halted in this cold and foodless bottom water and they avoid ascending to the hot surface water, which is regarded as an over-summering strategy. Based on discrete water sampling approaches, previous studies demonstrated that higher chlorophyll a (Chl a) levels appeared in the mixed hot surface water layer; however, the subsurface chlorophyll a maximum layer (SCML) has seldom been described. In the present study, various probes and a visual plankton recorder (VPR) were used to determine the fine vertical distributions of environmental factors and C. sinicus. VPR observations showed the ecological responses in fine scale and indicated that few C. sinicus individuals ascend at night, the main population preferred to remain below the SCML all day long. The results demonstrated that a constant thin SCML existed in the YSCWM area, and that the SCML location coincided with or was beneath the thermocline and halocline layers, where the temperature was suitable for C. sinicus. The relationship between abundance and Chl a, showed the diel vertical migration trend of C. sinicus to feed at night in the YSCWM area. In addition to temperature as a main influencing factor, dissolved oxygen concentrations and column depth were also influencing factors. Therefore, in addition to avoiding high surface temperature, energy supplement may be an important driving force confining the diel vertical migration of C. sinicus in the Yellow Sea in summer.

Net Ecosystem CO2 Flux and Effect Factors in Peatland Ecosystem of Central China

Peatland ecosystems play an important role in the global carbon cycle because they act as a pool or sink for the carbon cycle. However, the relationship between seasonality effect factors and net ecosystem CO2 exchange (NEE) remains to be clarified, particularly for the non-growing season. Here, based on the eddy covariance technique, NEE in the peatland ecosystem of Central China was examined to measure two years’ (2016 and 2017) accumulation of carbon dioxide emissions with contrasting seasonal distribution of environmental factors. Our results demonstrate the cumulative net ecosystem CO2 emissions during the study period was in the first non-growing season 2.94 ± 4.83 μmolCO2 m-2.s-1 with the lowest values in the same year in first growing season was -2.79 ± 4.92 μmolCO2 m-2.s-1. The results indicate the effect of seasonal variations of NEE can be directly reflected in daily and seasonal variations in growth and respiration of peatland ecosystem by environmental parameters over different growing stages.

Effects of canopy microclimate on fruit yield and quality of Camellia oleifera

Abstract This study investigated the relationship between environmental factors and the fruit yield, quality, and tree structure of Camellia oleifera by studying the relationship between the canopy microclimate, fruit yield, and fruit quality. The distributions of environmental factors over a year, and fruit yield and quality at fruit maturity in the canopy were investigated by measuring the differences between the inner canopy of the lower layer, outer canopy of the lower layer, inner canopy of the middle layer, outer canopy of the middle layer, inner canopy of the upper layer, and outer canopy of the upper layer. Light intensity was significantly different in the various layers, but there were no significant changes in temperature and relative humidity. Fruit yield and quality were related to light intensity, which improved from bottom to top and from the inner to outer canopy. They had positive correlations with the annual average light intensity and temperature, but were inversely associated with the annual average relative humidity. The fruit yield and oil content ratio in fresh fruit varied between the inside of the bottom to the outside of the top canopy. Yield and quality of fruit between July and October had higher mean correlation coefficients with light intensity (r = 0.807), temperature (r = 0.812) and relative humidity (r = −0.863). Additionally, regression equations between fruit characteristics and the canopy microclimate between July and October could be used evaluate the fruit yield and quality.

Operational Conditions in Regulatory Benchmarking Models: A Monte Carlo Analysis

Benchmarking methods are widely used in the regulation of firms in network industries working under heterogeneous exogenous environments. In this paper we compare three recently developed estimators, namely conditional DEA (Daraio and Simar, 2005, 2007b), latent class SFA (Orea and Kumbhakar, 2004; Greene, 2005), and the StoNEZD approach (Johnson and Kuosmanen, 2011) by means of Monte Carlo simulation focusing on their ability to identify production frontiers in the presence of environmental factors. Data generation replicates regulatory data from the energy sector in terms of sample size, sample dispersion and distribution, and correlations of variables. Although results show strengths of each of the three estimators in particular settings, latent class SFA perform best in nearly all simulations. Further, results indicate that the accuracy of the estimators is less sensitive against different distributions of environmental factors, their correlations with inputs, and their impact on the production process, but performance of all approaches deteriorates with increasing noise. For regulators this study provides orientation to adopt new benchmarking methods given industry characteristics.

A study of the distribution ranges of small mammals in southeastern Transbaikalia using ecological niche-based modeling methods

Distribution models have been constructed for 36 species of small mammals from southeastern Transbaikalia. The initial data used for modeling are the distribution of environmental factors (climate data and remote sensing of the earth surface) in the set of localities where each of the species was caught. The species distribution ranges are explainable by the distribution of environmental factors in 30 cases out of 36; 17 of them are explainable by only one or two environmental factors. As for the remaining six cases, it is likely that historical factors and interspecific competition have considerably influenced the current distribution. The modeling results for these six species make it possible to propose hypotheses about the reasons underlying the current distributions, which cannot be proposed without using such a modeling approach.

A Geospatial Dynamic Microsimulation Model for Household Population Projections

Forecasting Populations (FPOP) is a microsimulation model (MSM) that is the demographic core of an extensible modeling framework. The framework, with FPOP at its core, enables the geospatial projection of a population under purely demographic processes or under the additional influence of exogenous factors such as disease, policy changes and prevention programs, or environmental stressors. Empirically-derived transition probabilities of life events such as birth, death, marriage, divorce and migration, captured in lookup table format, drive the simulation. These transition probabilities can be modified dynamically by external user-defined functions or other external MSMs. The use of MSM structures and methodologies enables FPOP to portray the impact of heterogeneity in the geospatial dimension (e.g., distribution of environmental factors or distribution of intervention programs), as well as the social dimension (e.g., household or social network correlates), on the projections. POP is designed and structured

Influence of environmental factors on the spatial distribution and diversity of forest soil in Latvia

This study was carried out to determine the spatial relationships between environmental factors (Quaternary deposits, topographical situation, land cover, forest site types, tree species, soil texture) and soil groups, and their prefix qualifiers (according to the international Food and Agricultural Organization soil classification system World Reference Base for Soil Resources (FAO WRB)). The results show that it is possible to establish relationships between the distribution of environmental factors and soil groups by applying the generalized linear models in data statistical analysis, using the R 2.11.1 software for processing data from 113 sampling plots throughout the forest territory of Latvia. A very high diversity of soil groups in a relatively similar geological structure was revealed. For various reasons there is not always close relationship between the soil group, their prefix qualifiers and Quaternary deposits, as well as between forest site types, the dominant tree species and specific soil group and its prefix qualifiers. Close correlation was established between Quaternary deposits, forest site types, dominant tree species and soil groups within nutrient-poor sediments and very rich deposits containing free carbonates. No significant relationship was detected between the CORINE Land Cover 2005 classes, topographical situation and soil group.

Encrusting protected reef Hon Nai in Cam Ranh Bay in the South China Sea

A protected non-structural reef in Сam Ranh Bay in southern Vietnam was surveyed. A high diversity was found among scleractinian and accompanyingmass species of macrobenthos. Thirty- four species were identified only among genera Acropora; it made 80% of the total composition of these Scleractinian on reefs of Vietnam and a quarter of the total abundance of these corals on reefs in the Indo-Pacific. A new species, Favites сamranensis sp. nov, earlier unknown for science, has been found. The vertical bionomic zonality corresponding to zonal distribution of environmental factors on the reef under study is similar to that on reefs of the Siam Bay, different regions of the Pacific and the Caribbean Basin. Expansion of prosperous state of the reef and minimization of anthropogenic influence on some reefs of Vietnam had a positive effect on their state. It is supposed, that the reef at Hon Nai islandis obliged by the prosperity to security measures and minimization of the anthropogenous influence, provided with the decision of government SRV and company “Sanest”.

Composition and abundance of the zooplankton community in the Bitter Lakes, Egypt, in relation to environmental factors

The taxonomic composition of the zooplankton community of the Bitter Lakes, Egypt, was examined in 2003–2004 in relation to the spatial and temporal distribution of environmental factors. Copepoda were dominant, forming 49% of the zooplankton, followed by Protista at 37%. During the autumn, zooplankton in Small Bitter Lake were more abundant and different in composition, when compared with zooplankton populations in Great Bitter Lake. The high abundance of copepods in Small Bitter Lake occurred under conditions of elevated salinity, whereas lower salinity allowed rotifers and other freshwater forms to flourish near the outlet of a canal carrying urban waste. A reduction in zooplankton abundance was observed in an area impacted by heated water from the outlet of an electric power station.

Geographic Assessment of Present Protected Areas in Japan for Representativeness of Forest Communities

Most assessments of present protected areas have focused on which features are or are not represented and to what extent, but they have not considered the environmental gradients and the geographic context within each biodiversity feature under a conservation network. We examined how protected areas are distributed with respect to the distribution of six forest community types. Three analyses were applied to the dataset in the Red Data Book of Plant Communities in Japan and the related survey: (1) recursive partitioning was used to contrast environmental factors of conserved communities with nonconserved communities; (2) point pattern analysis, based on Ripley's K function, was used to describe the spatial pattern of conserved communities; and (3) the spatial scan statistic was used to detect spatial representation gaps. Overall, environmental bias was greatest in relation to soil and topography. However, the results of point pattern analysis showed that the spatial pattern of conserved communities did not depend entirely on the distribution of environmental factors. Four types of gaps in spatial representation were detected by the spatial scan statistic, irrespective of environmental bias. These results showed that although a community type might be well protected in total or along the environmental gradients, conserved communities might not capture the full range of geographic context. To ensure appropriate representation or protection, it is important that conservation planning for protected areas take into account both the environmental gradients and the geographic context within each biodiversity feature.

Heterogeneous distribution of environmental factors and zooplankton in a vegetated area of a eutrophic lake

Heterogeneous distribution of environmental factors and zooplankton in a vegetated area of a eutrophic lake

Assessing the representativeness of the wet tropics of Queensland world heritage property

An assessment is made of the representativeness of the Wet Tropics World Heritage property of north-east Queensland, Australia. The relevance of this feature to the World Heritage criteria is discussed. Computer-based spatial data sets are used to provide a sample of the distribution of key environmental factors at both continental and regional scales. Numerical classification techniques are applied to generate environmental groups from pattens in the distribution of these environmental factors. An evaluation is presented of the representation of these groups within the World Heritage property, in the context of present and potential tropical forest cover.