Low Nutrient Levels Research Articles

Distinct sources of bacterial branched GMGTs in the Godavari River basin (India) and Bay of Bengal sediments

Branched glycerol monoalkyl glycerol tetraethers (brGMGTs) are a group of membrane-spanning lipids produced by (yet) unidentified bacteria. They are characterized by a C-C bond connecting the two alkyl chains, which is thought to enhance membrane stability at higher temperatures. So far, they have been found in peats, lakes, and marine sediments, where their abundance relative to that of branched glycerol dialkyl glycerol tetraethers (brGDGTs) increases with temperature. However, the preferred niche(s) for production and the origin of brGMGTs in the terrestrial and marine realm remain unknown. Here we explore the occurrence of brGMGTs in soils, suspended particulate matter (SPM) and riverbed sediments in the Godavari River basin, and compare these with brGMGTs in a Holocene sediment core from the Bay of Bengal close to the Godavari River mouth. BrGMGTs are mostly detected in agricultural and/or regularly inundated soils, and in the river at sites with standing water and/or agricultural/wastewater effluents, as well as in the delta, where low oxygen conditions and/or high nutrient levels prevail. In contrast, brGMGTs are continuously present in the marine sediment core, but with a different isomeric composition than in the terrestrial realm, indicating a primarily marine source. The stable brGMGT distribution downcore and brGMGT-inferred temperature estimates which resemble the bottom water temperature, may suggest marine brGMGT production in the deep water column and/or sediments. However, to establish the proxy potential of brGMGTs for paleoreconstructions in the terrestrial and marine realm, brGMGT sources and environmental controls require further study.

TDZ induces a dual morphogenetic pathway on leaf explants of the beach huckleberry – Gaylussacia brasiliensis

Gaylussacia brasiliensis is a bush from the Ericaceae family native to South America. It is considered an underutilized fruit species, despite its importance as a food source, medicinal plant, and forage for the native fauna. In the Florianópolis island, south of Brazil, it occurs in sand deposits between the Atlantic Ocean and the mountain chains of the Atlantic Rain Forest, in a vegetation type called “Restinga”, a harsh environment where plants are exposed to stressful conditions. Constand winds, high solar radiation, saltwater sprays, and low nutrient levels are common in the Restinga environment, making G. brasiliensis an important genetic resource to face the expected effects of climate change. Despite its importance, there are no sexual or asexual protocols available for its propagation. This is the first record of a micropropagation protocol for a plant of the Gaylussacia genus. We report a reliable protocol for in vitro establishment of G. brasiliensis cultures from seeds, and an efficient micropropagation protocol using leaf explants. A dual regeneration pathway, i.e., somatic embryos and adventitious shoots, can be obtained directly from leaf explants without an intermediating callus tissue. A low concentration of TDZ can be used to achieve this goal, and a high number of plants can be obtained rapidly, allowing advances in the research of this underutilized plant species and enabling its propagation for commercial or conservation purposes.

Leukemia Cells Resistant to Glutamine Deprivation Express Glutamine Synthetase Protein

Objective:Low glutamine levels have been shown in tumor environments for several cancer subtypes. Therefore, it has been suggested that cancer cells rewire their metabolism to adopt low nutrient levels for survival and proliferation. Although glutamine is a non-essential amino acid and can be synthesized de novo, many cancer cells including malignant hematopoietic cells have been indicated to be addicted to glutamine. This study aimed to investigate the proliferation of leukemia cell lines in glutamine-deprived conditions.Materials and Methods:Cell proliferation of K562, NB-4, and HL-60 cells was determined by calculating cell numbers in normal vs. low glutamine media. Changes in mRNA expressions were investigated using qRT-PCR. The glutamine synthetase (GS)-encoding GLUL gene was knocked out (KO) in HL-60 cells using the CRISPR/Cas9 method and protein expression was evaluated with immunoblotting.Results:The proliferation of all cell lines was decreased in glutamine-deprived medium. GS protein expression was increased in glutamine-limited medium although the mRNA level did not change. Increased protein expression was confirmed with inhibition of new protein synthesis by treating cells with cycloheximide. To further investigate the role of GS protein, the GS-encoding GLUL gene was KO in HL-60 cells using the CRISPR/Cas9 method. GS KO cells proliferated less compared to control cells in glutamine-limited medium.Conclusion:Our results indicate that upregulated GS protein expression is responsible for glutamine addiction of leukemia cell lines. Exploiting the genetic and metabolic mechanisms responsible for GS protein expression could lead to the identification of new anti-cancer drug targets.

Review on the Integrated Use of Organic and Inorganic Fertilizers on Production and Soil Fertility in Ethiopia

Depletion of soil fertility is the main problem to sustain agricultural production and productivity in many countries. Soil fertility decline is a big issue in the Agriculture of Ethiopia. Soils in Ethiopian have low levels of plant nutrients due to its removal by erosion and leaching by high rainfall. One of the major constraints for crop production in the Ethiopia is improper nutrient management. The Organic fertilizer improves physical and biological activities of soil but they have comparatively low in nutrient content, so larger quantity is required for plant growth. However, inorganic fertilizer is usually immediately and fast containing all necessary nutrients that are directly accessible for plants, but continuous use of inorganic fertilizers alone causes soil organic matter: degradation, soil acidity, and environmental pollution. So, the integrated nutrient management system is an alternative system for the sustainable and cost-effective management of soil fertility by combined apply of inorganic with organic materials resulting in rising soil fertility and productivity without affecting the environment. An experiment on organic and inorganic fertilizer application and its effect on yield of wheat and soil chemical properties of Nitisols the research finding out put at Holetta Agricultural Research Center in 2014 to 2015 these results of soil analysis after harvesting revealed that application of organic fertilizer improved soil pH, OC, total N and available P, the highest wheat grain and biomass yield (6698 kg/ha and 19417 kg/ha respectively) were obtained from the application of 50% VC and 50% N and P followed by full dose of recommended rate N and P from inorganic fertilizer resulting in 6241 kg/ha grain and 18917 kg/ha biomass yields respectively. This review indicated that different crops has showed significance response to the combined soil fertility management treatments containing both organic and inorganic forms under farmers’ field condition that they could be considered as alternative options for sustainable soil and crop productivity in the soil fertility degraded of soil in Ethiopia. To maintain soil fertility, farmers have to take note of the characteristics and constraints of their soils and use sustainable management practices to conserve and improve fertility. Farmers deliberately incorporate household refuse, crop residues, animal manures, compost, biofertilizer and inorganic fertilizer into compound farm soils with the sole purpose of improving soil fertility and to enhance crop productivity. The objective of this review has assessed the effects of integrated organic and inorganic fertilizers on soil fertility and productivity. The review revealed that the appropriate application of organic with inorganic fertilizers increases productivity without negative effect on yield quality and improves soil fertility than the values obtained by organic or inorganic fertilizers separately. Therefore, farmers will be adopting this technology for increasing the crop yield and soil fertility. Keywords: Soil fertility, Organic Fertilizer, Inorganic Fertilize, Integrated Nutrient Management DOI: 10.7176/JBAH/12-3-02 Publication date: February 28 th 2022

Adaptative Leaf Morphology of Eurya japonica Thunb. (Ternstroemiaceae) in Serpentine Areas

Serpentine soils are known to affect plant growth and plants in these soils have morphological and anatomical modifications. Comparative leaf morphology and anatomy studies of Eurya japonica Thunb. was conducted between serpentine and inland (control) areas. Our morphological analyses revealed that the individuals in the serpentine areas had significantly smaller and thicker leaves than those in the inland areas. Our anatomical analyses showed that the smaller leaves of serpentines had decreased numbers of cells, and their thicker leaves contributed to the increased height of epidermal cells, palisade tissue, and spongy tissue. Furthermore, the stomatal size of serpentines was significantly smaller than those from the inland areas. We concluded that E. japonica adapted to the serpentine areas by decreasing leaf size due to low levels of nutrients, by thickening the leaves to store water and reducing the stomatal size to minimize water loss via gas exchange.

Elevated-CO2 and nutrient limitation synergistically reduce the growth and photosynthetic performances of a commercial macroalga Gracilariopsis lemaneiformis

The oceans absorb a large amount of CO2 from the atmosphere, which leads to the increase of ocean acidity. Due to the uncoordinated absorption ratio of N and P in macroalgae cultivation, the nutrients in coastal areas are limited. At present, there are relatively few studies on ocean acidification combined nutrients limitation on commercial macroalgae. This study investigated the economically important red algae Gracilariopsis lemaneiformis, and explored its physiological responses under the combination conditions of ocean acidification and nutrients limitation. In this study, Gracilariopsis lemaneiformis were cultured under two CO2 conditions (400 and 1000 μatm) and four nutrient conditions (HN, 103.1 μmol L−1; LN, 3.1 μmol L−1; HP, 10.1 μmol L−1; LP, 0.1 μmol L−1). The results showed that elevated CO2 had no significant effect on G. lemaneiformis growth under P sufficiency (10.1 μmol L−1) but was significantly reduced under P limitation (0.1 μmol L−1). Especially under N (3.1 μmol L−1) and P (0.1 μmol L−1) limitation, the elevated CO2 had the most significant negative impact on the growth of G. lemaneiformis. Under elevated CO2, P limitation reduced the net photosynthetic rate and relative electron transport rate of G. lemaneiformis. In addition, the dual limitation of LNLP significantly reduced the chlorophyll a content but increased the phycocyanin content under elevated CO2. At low nutrient levels, the elevated CO2 significantly reduced carotenoid, phycoerythrin and soluble protein contents. Our findings suggested that ocean acidification and nutrient limitation synergically inhibited the growth and photosynthetic performances of G. lemaneiformis, and P limitation has a greater effect on G. lemaneiformis. The results can provide valuable information for the seedling field cultivation and selective breeding of G. lemaneiformis in the future.

Spatiotemporal Distribution of Cladocera and Rotifer of the Mangrove Waters of Mouanko (Coastal Cameroon): Influence of Some Abiotic Variables

The Mouanko mangrove is subjected to major anthropogenic activities such as agriculture, fishing and deforestation, hence information on Cladocerans and Rotifers amongst other aquatic organisms in order to monitor and manage this ecosystem is vital. The aim of this work is to study the physicochemical parameters of the environment that influence the diversity and spatiotemporal distribution of Cladocerans and Rotifers in the mangrove waters of Mouanko. This study was carried out from November 2019 to October 2020 at 8 sampling stations. Both biological and physico-chemical sampling and analyses were done following standard recommendations. The results of the phyico-chemical analyses revealed that the waters of the Mouanko mangroves were slightly basic (7.64 ± 0.71 UC), moderately oxygenated (69.56% ± 14.29%) with low levels of nutrients [ NO -2 (0. 06 ± 0.05 mg/L), NH+4 (0.39 ± 0.3 mg/L) and PO3-4 (up to 0.12 mg/L)] and high values of electrical conductivity (up to 6531.04 μS/cm), salinity (up to 3.71‰). 15 species of Cladocerans and 30 species of Rotifers were identified accounting for a total abundance of 612 ind/L. The species richness was higher in freshwater influenced zones (40 taxa) compared to marinewater influenced zones (17 taxa). Among these species, the Cladocera, Penilia avirostris was the most abundant in marinewater influenced zones (84 ind/L) while the Rotifer, Keratella tecta was the most abundant in freshwater influenced zones (64 ind/L). Shannon-Weaver’s diversity and Pielou’s equitability indices indicated that freshwater influenced zones host a diverse community with a tendency towards equi-partition of species while marinewater influenced zones revealed the opposite. The low levels of organic pollution indicator variables recorded and the high diversity of the freshwater influenced zones population studied attested to the low level of anthropization in this environment. High salinity and electrical conductivity values influence the distribution of these organisms.

Influência dos níveis de nutrientes, tempo de viagem e disponibilidade de luz nas concentrações de clorofila-a fitoplanctônica em uma bacia de rio neotropical

Abstract: Aim Knowledge of the factors influencing the biomass of phytoplankton in rivers is important with reference to the characterization of water quality and predicting the effects of environmental change on such ecosystems. The present study quantified the concentrations of chlorophyll-a in the water column of the Miranda River Basin, located in western Brazil, contributing to form the Pantanal Wetland, and attempted to identify the primary environmental influences on the phytoplankton biomass. Methods Temperature, depth, current speed, turbidity, Secchi transparency and concentrations of nutrients, suspended solids and chlorophyll-a were measured at approximate monthly intervals during the course of a year, at five upland and three lowland sites. Relationships between chlorophyll-a and nutrient concentrations, travel times and light availability were examined. Results Nutrient levels were generally low, being oligo- to mesotrophic. High levels of suspended solids were recorded (up to approximately 250 mg.L-1), especially in the rainy season at the upland sites. The latter showed low chlorophyll-a concentrations, while lowland sites, with the exception of one, showed two peaks, one in winter (dry season) and the other in summer (wet season), of 4.9 and 2.4µg.L-1, respectively, coincident with reduced concentrations of suspended solids. Conclusions The low nutrient levels recorded may have been due to the main land use being cattle rearing. The high solids concentrations found may have been due to the degradation of native vegetation, especially riparian, that has occurred over the past decades. Travel times of approximately three to four days may have been a factor in retarding algal abundance in the upland sites, as opposed to approximately ten days in the lowland sites, where light limitation may have been a factor reducing algal growth.

The Role of the Inflammatory Response in Mediating Functional Recovery Following Composite Tissue Injuries.

Composite tissue injuries (CTI) are common among US Military Service members during combat operations, and carry a high potential of morbidity. Furthermore, CTI are often complicated due to an altered wound healing response, resulting in part from a dysregulation of the innate and adaptive immune responses. Unlike normal wound healing, in CTI, disruptions occur in innate immune responses, altering neutrophil functions, macrophage activation and polarization, further impacting the functions of T regulatory cells. Additionally, the biological underpinnings of these unfavorable wound healing conditions are multifactorial, including various processes, such as: ischemia, hypoxia, low nutrient levels, and altered cell metabolic pathways, among others, all of which are thought to trigger anergy in immune cells and destabilize adaptive immune responses. As a result, impaired wound healing is common in CTI. Herein, we review the altered innate and adaptive immune cells and their metabolic status and responses following CTI, and discuss the role a multi-pronged immunomodulatory approach may play in facilitating improved outcomes for afflicted patients.

Cultural treatments in pineapple crop. Management for high yield – Review

Several factors influence in the vegetative development, yield and quality of pineapple fruits, among which the cultural treatments adopted throughout the production cycle stand out, mainly weed control, mineral nutrition, irrigation and induction artificial flowering. The purpose of this review was to present the main advances in research on cultural treatments in the cultivation of pineapple (Ananas comosus L. Merril) and their effects on yield and fruit quality. Current research shows that interventions for weed management, through chemical control with herbicides or the adoption of organic or inorganic soil cover are strategies that can be adopted by producers who seek to reduce labor costs and provide good conditions for plant development. The use of mulching is a promising and effective practice, given the cost reduction with polluting herbicide applications and improvement of the physicochemical quality of the soil. Regarding mineral nutrition, pineapple is a rustic plant, tolerant to soils with moderate acidity and low levels of nutrients in the soil, however, liming and fertilization are essential for crops where high yields are sought. In the same way, it is verified that the pineapple, even being a CAM metabolism plant, tolerant to situations of water stress, is highly responsive to irrigation, which provides improvements in the vegetative and reproductive development of the plant. Another essential management practice in pineapple crops is artificial floral induction, a practice that aims to synchronize the flowering period, facilitate harvesting and ensure a consumer market in times when the supply of fruit is scarce

Landscape‐level vegetation conversion and biodiversity improvement after 33 years of restoration management in the Drentsche Aa brook valley

Effects of restoration management on peatlands formerly used for intensive agriculture are rarely evaluated or discussed over larger spatial and temporal scales. Here, restoration of the Drentsche Aa brook valley was evaluated at the landscape level. Detailed vegetation maps were used with 1982 serving as the baseline, 1994 representing vegetation before rewetting, and 2015 after rewetting. Based on the mapping typology and phytosociological records, 15 main vegetation types were distinguished. Species richness and Shannon index values were calculated as plant diversity indicators, and the number of rare species was used as a rarity indicator. Basic landscape metrics were evaluated as measures of spatial heterogeneity. Results after restoration measures showed extensive vegetation type conversions clearly pointed to lower nutrient levels, and an increase in marsh vegetation at the cost of wet meadows. Significantly higher landscape heterogeneity was achieved, while biodiversity indicators showed small differences over time due to a mixture of positive and negative changes at different locations. This study shows that long‐term restoration management on agricultural peatlands can be successful at landscape level. Our experience highlights the importance of continuity in management given the prolonged influence by intensive agriculture, both from former land uses and from the surrounding valley flanks.

Biological Flora of the British Isles: Salvia pratensis

Abstract This account presents information on all aspects of the biology of Salvia pratensis L. (Meadow Clary) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation. Salvia pratensis is an erect, rosette‐forming, perennial herb with a broad native distribution covering much of Europe—from the British Isles, Spain and Morocco in the west, across Europe into Asia, as far east as the Urals. In the British Isles, the species is nationally scarce, confined to a few south‐ to west‐facing sites with calcareous soils in Southern England and one site in Wales. It is predominately found in unimproved pasture, hay meadows and grassy verges, but can occur on the fringes of scrub or woodland. Although the species is abundant in central Europe, changes to land management since the mid‐20th century have resulted in fragmented and threatened populations in several European countries. It is cultivated as an ornamental, as is S. × sylvestris, the hybrid with S. nemorosa. Populations are typically gynodioecious, having both female (male‐sterile) and hermaphrodite individuals at variable proportions. The species has a mixed mating system and is self‐compatible via insect pollination, but predominantly outcrosses. Honeybees and bumblebees are abundant pollinators, but a diverse range of bee species and other insect species visit S. pratensis flowers. Inbreeding depression has been documented, presenting a conservation concern for small, fragmented populations. The species is the focus of conservation efforts and has been reintroduced to sites where it had become locally extinct in Britain. To sustain favourable habitat, site management should maintain low soil nutrient levels, and prevent scrub encroachment and the dominance of coarse grasses. The removal of sward by hay cutting or grazing after plants have flowered and set seed is advised, in addition to maintaining a degree of disturbance to provide bare patches of soil for seedling recruitment.

Performance of Centrocema grown on mercury-contaminated tailing inoculated with beneficial bacteria: Preliminary study

Low levels of major essential nutrients and high mercury (Hg) content in gold mine tailings can inhibit plant growth. An inexpensive and effective strategy to overcome these obstacles was inoculation of plant-growth promoting bacteria and planting legume cover crops (LCC). A greenhouse experiment was conducted to evaluate the effect of isolates of Nitrogen Fixing Bacteria (NFB) and Phosphate Solubilizing Bacteria (PSB) on some growth characteristics of LCC Censtrosema pubescens (butterfly pea) grown in Hg-contaminated tailing of gold mine tailing. Moreover, the research was aimed to verify the viability of two bacterial groups in tailing after inoculation. The experiment was set up in randomized block design to test single and mixed inoculation of NFB and PSB. The experiment verified that the single inoculation and mixture of two bacteria did not change plant properties compared to the control treatment. Although the statistical analysis was not significant, there were slightly increase in root length as well as NFB and PSB populations of inoculated plants.

Genome sequencing and identification of cellulase genes in Bacillus paralicheniformis strains from the Red Sea

BackgroundCellulolytic microorganisms are considered a key player in the degradation of plant biomass in various environments. These microorganisms can be isolated from various environments, such as soils, the insect gut, the mammalian rumen and oceans. The Red Sea exhibits a unique environment in terms of presenting a high seawater temperature, high salinity, low nutrient levels and high biodiversity. However, there is little information regarding cellulase genes in the Red Sea environment. This study aimed to examine whether the Red Sea can be a resource for the bioprospecting of microbial cellulases by isolating cellulase-producing microorganisms from the Red Sea environment and characterizing cellulase genes.ResultsThree bacterial strains were successfully isolated from the plankton fraction and the surface of seagrass. The isolated strains were identified as Bacillus paralicheniformis and showed strong cellulase activity. These results suggested that these three isolates secreted active cellulases. By whole genome sequencing, we found 10 cellulase genes from the three isolates. We compared the expression of these cellulase genes under cellulase-inducing and non-inducing conditions and found that most of the cellulase genes were generally upregulated during cellulolysis in the isolates. Our operon structure analysis also showed that cellulase genes form operons with genes involved in various kinds of cellular reactions, such as protein metabolism, which suggests the existence of crosstalk between cellulolysis and other metabolic pathways in the bacterial isolates. These results suggest that multiple cellulases are playing important roles in cellulolysis.ConclusionsOur study reports the isolation and characterization of cellulase-producing bacteria from the Red Sea. Our whole-genome sequencing classified our three isolates as Bacillus paralicheniformis, and we revealed the presence of ten cellulase orthologues in each of three isolates’ genomes. Our comparative expression analysis also identified that most of the cellulase genes were upregulated under the inducing conditions in general. Although cellulases have been roughly classified into three enzyme groups of beta-glucosidase, endo-β-1,4-glucanase and exoglucanase, these findings suggest the importance to consider microbial cellulolysis as a more complex reaction with various kinds of cellulase enzymes.

Effect of citric acid in low nutrient diet on growth and bone mineral metabolism of broiler

The study was conducted to observe the performance of broiler in low level of dietary nutrients but using citric acid (CA) as feed additive. A total of 240 day old straight run broiler chicks (COBB 500) were randomly distributed into eight groups, with three replicate cages having 10 birds in each. Control diet (Group 1) was formulated with corn-soybean based ingredients contained 22.7% CP and 3213 kcal ME/kg. Other dietary Groups 2, 3, 4, 5, 6, 7 and 8 were control+0.5% CA, control+4% low protein and energy, control+4% low protein and energy with 0.5% CA, control+8% low protein and energy, control+8% low protein and energy with 0.5% CA, control+12% low protein and energy and 12% low protein and energy with 0.5% CA, respectively. At the age of 31 days 8% lowering the protein and energy could compensate by the addition of citric acid (group 6). There was no significant difference of total feed intake among the groups. As live weight 8% lowering the protein and energy could compensate the feed efficiency when addition of CA. Tibia ash was determined in first four groups that were 44.2, 49.5, 46.8 and 47.1% in group 1, 2, 3, and 4, respectively. The mortality was 0.0% during the whole experimental period. The cost of production (BDT/kg broiler) was lowest in group 8, that means lowering protein and energy reduces feed cost. It may be concluded that diets containing low protein and energy up to 8% but addition of 0.5% citric acid would compensate the performance of broiler, but 12% reduction of energy and nutrients is cost effective.
 Bang. J. Anim. Sci. 2021. 50 (1):36-42

Zooplankton communities and their relationship with water quality in eight reservoirs from the midwestern and southeastern regions of Brazil.

Zooplankton are widely recognised as being regulated primarily by predators and food availability. In reservoirs, the quantity and quality of food resources are generally affected by the characteristics of the water, which in turn are controlled by the flow pulse generated by operation of the dams. In this study, we investigated the relationship between zooplankton, water quality and food availability (phytoplankton) in eight hydroelectric reservoirs located in Brazil. Samples were collected during the rainy and dry periods between 2008 and 2009. In general, the reservoirs exhibited mesotrophic conditions and Cyanobacteria were the predominant phytoplankton. The results showed that the rotifers Kellicottia bostoniensis, Hexarthra mira, Keratella spp., and Polyarthra vulgaris were present, indicating nutrient-rich environments. In addition, the copepod Thermocyclops decipiens occurred in eutrophic environments. In contrast, the cladoceran Daphnia gessneri and copepod Notodiaptomus henseni were considered indicators of more desirable water quality, owing to their relationship with waters with lower levels of nutrients and suspended solids. The results support the use of these organisms as a useful tool for understanding changes in water quality and in the ecosystem processes involved.

A nutrient recommendation system for soil fertilization based on evolutionary computation

In agricultural production, soil characteristics play a vital role in maintaining fertility by allowing crops to develop better through root nutrition with minimal energy inputs. Nitrogen (N), Phosphorus (P), and Potassium (K) are all important nitrogen fertilizers extensively utilized in crops to supply a sufficient level of nutrients and keep their production level high. However, the application is generally limited to specific crops because of the global variability in these essential nutrients. Stability in fertilizer application, growth, and root growth rate increases crop fertility and crop production. To predict the suitable nutrients for different crops and provide nutrients recommendations by analyzing the crop fertility and yield production, this paper proposes nutrient recommendations through an improved genetic algorithm (IGA) that uses time-series sensor data and recommends various crop settings. A neighborhood-based strategy is then presented to handle exploration and exploitation for optimizing the parameters to obtain the maximum yield. The method can expand knowledge by using the population exploration strategy. The final recommendation is made by using the similarity between recommended patterns and real-time sensor data. With time, crop fertility decreases due to the low level of nutrients. This crop model will help to increase yield by analysis of the seasonal fertility performance of the soil. The proposed method is also a useful tool to improve soil fertility performance by providing the nutrient recommendation of optimal conditions for crop development. Experimental results show that the proposed model can recommend optimizing patterns and increasing the yearly yield efficiently. The method can help identify the region to assess crop suitability under certain nutrients levels and give insight into nutrient suitability assessments concerning specific crops in a climate-changing world.

Growth and diet of inanga (Galaxias maculatus) within a small New Zealand coastal pond system

ABSTRACT Inanga (Galaxias maculatus) are found in a range of freshwater habitats around much of the Southern Hemisphere. Although they are reasonably well studied within New Zealand, little is known about the populations found in coastal pond systems. This study focussed on inanga diet and population dynamics within a shallow pond complex in coastal Southland, investigating age, growth, distribution, and diet of juvenile inanga over a spring to autumn period. Otolith analysis indicated a three-month period (September to November) during which fish are hatching, with fish that hatched earlier growing more slowly than later fish. Inanga were found in only one location within the pond complex – a site featuring low water nutrient levels and less access by trout. Diet analysis showed high selectivity for chydorids and chironomid larvae, indicating a mixture of both benthic and pelagic foraging. Overall, this study has provided insight into inanga population dynamics in ponds, which have not previously been observed.

Revealing anthropogenic effects on lakes and wetlands: Pollen-based environmental changes of Liangzi Lake, China over the last 150 years

Lakes and wetlands in populated areas have become very vulnerable to pollution and habitat degradation, seriously threatening regional ecological security and socio-economic development. Exploring long-term environmental changes in these systems is essential to reveal the interactions of human activities and catchments, and further to provide valuable reference for current restoration. In this paper, we present paleolimnological data from a short sedimentary core from Liangzi Lake, a typical wetland nature reserve in the middle and lower Yangtze River Basin, China. Multiple sedimentary proxies (principally pollen but also geochemistry and grain size data) combined with historical records were used to establish environmental changes of Liangzi Lake, in both terrestrial and lacustrine aspects, over the last 150 years. Despite the influence of hydrological processes to some extent, our results indicate that the anthropogenic effects (negative and positive) are well recorded by the sedimentary records. The landscape changes of the wider Liangzi Lake wetland can be placed into four stages: less disturbed background (before the 1950s), hydrological regulation (1950s–1960s), intensive reclamation (1970s–1990s), and wetland restoration (starting in the late 1990s). Agriculture and hydrological control were the most important factors in transforming the wetland landscapes, as well as the aquatic ecosystem. The changes in the lake itself could be divided into three main stages: low nutrient levels and unstable hydrologic condition with dominant emergent plants (before the 1960s), rising nutrient levels and a stable water environment with increasing submerged plants (1960s–1990s), and high nutrient and pollution levels with the subsequent adjustment and restoration (after the late 1990s). Our study provides a comprehensive history of environmental changes of a typical inland lake and its surrounding wetland, and may contribute to future wetland conservation in similar regions, as well as pollen-based environmental reconstruction studies.

Correction to: Chronic low-level nutrient enrichment benefits coral thermal performance in a fore reef habitat

Correction to: Chronic low-level nutrient enrichment benefits coral thermal performance in a fore reef habitat