255 research outputs found
Flies on the move: an inherited virus mirrors Drosophila melanogaster's elusive ecology and demography.
No full textJournal ArticleResearch Support, Non-U.S. Gov'tCopyright © 2014 John Wiley & Sons LtdThis is the accepted version of the following article: Wilfert, L. and Jiggins, F. M. (2014), Flies on the move: an inherited virus mirrors Drosophila melanogaster's elusive ecology and demography. Molecular Ecology, 23: 2093–2104. doi: 10.1111/mec.12709, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/mec.12709/abstractVertically transmitted parasites rely on their host's reproduction for their transmission, leading to the evolutionary histories of both parties being intimately entwined. Parasites can thus serve as a population genetic magnifying glass for their host's demographic history. Here, we study the fruitfly Drosophila melanogaster's vertically transmitted sigma virus DMelSV. The virus has a high mutation rate and low effective population size, allowing us to reconstruct at a fine scale how the combined forces of the movement of flies and selection on the virus have shaped its migration patterns. We found that the virus is likely to have spread to Europe from Africa, mirroring the colonization route of Drosophila. The North American DMelSV population appears to be the result of a recent single immigration from Europe, invading together with its host in the late 19th century. Across Europe, DMelSV migration rates are low and populations are highly genetically structured, likely reflecting limited fly movement. Despite being intolerant of extreme cold, viral diversity suggests that fly populations can persist in harsh continental climates and that recolonization from the warmer south plays a minor role. In conclusion, studying DMelSV can provide insights into the poorly understood ecology of D. melanogaster, one of the best-studied organisms in biology.Leverhulme TrustRoyal Society University Research Fellowshi
Effects of agricultural land-use on pollination services
No full textPollinators are vital for ecosystem functioning, biodiversity conservation and food production by pollinating a majority of crops and wild flowering plants. In agricultural areas, pollinators are threatened by a variety of stressors including e.g. the lack of floral resources or use of pesticides, which threatens their provision of pollination services. In this thesis, I investigated the impacts of agricultural land-use management on the provision of pollination services in agricultural areas. By measuring different indicators for pollinator health and pollination services in two important pollinator groups, bumblebees and syrphid flies, I aimed to identify key links between them and how they are affected by land-use intensification. Across all our studies, floral resource limitation was the main driver in affecting both pollinator health and pollination services. Different responses of both pollinator groups to environmental stressors emphasize the significance of considering the effects of land-use on different pollinator groups individually, e.g. by not generalizing from bees to other insect orders such as flies. For example, bumblebees were more sensitive to local land-use, while syrphid flies reacted mostly to landscape level factors. We further found that the effects of land-use on pollinator health were temporally stable across different years of sampling, showing that pollinators foraging in intensively used areas are under persistent pressure. This stability indicates that without significant changes in land-use practices, pollinators will continue to face substantial challenges in agricultural landscapes. Conservation strategies should focus on supporting flower-rich and diverse landscapes to support diverse and healthy pollinator communities. This approach not only benefits pollinators but also their provision of pollination services, which contributes to the overall functioning and productivity of agricultural ecosystems and ultimately affects human health
UBI MEL, IBI APES: On the evolutionary ecology of infectious diseases and intersections with apiculture.
No full textInfectious diseases shape almost every aspect of nature and society; understanding the multitude of factors influencing infectious diseases is a critical goal of modern evolutionary ecology. This thesis explores this broad topic using theoretical and empirical approaches to understand the forces at work in infectious disease ecology and evolution, with application to the specific system of managed honeybees (Apis mellifera L.). I demonstrate that a well-documented evolutionary trade-off governing pathogen resistance is both constitutive and genetic – critical for supporting assumptions made by mathematical theory. I go further to demonstrate that this trade-off breaks down when the action of selection is reversed, in that when the ‘cost of resistance’ phenotype is selective for, we do not incidentally select for higher resistance too. This is important for understanding genetic linkage of traits and downstream evolutionary modelling. I undertake theoretical modelling on the topic of spatial structure and how it affects pathogen evolution. In doing so I interrogate a critical assumption made in much of the prior theoretical body, showing that the effect of spatial structure on virulence is quantitatively changed when a core assumption concerning reproduction is relaxed, but is otherwise qualitatively robust. I continue on the theme of spatial structuring and pathogens by developing novel theoretical models on how changing apicultural management alters honeybee population spatial structure, surprisingly leading to only marginal changes in pathogen burden. I stay on this topic to examine empirical data on honeybee colony viriomes in an observation experiment showing that colonies from very intensively managed, migratory backgrounds show elevated viral titres – critical for management and wild bee conservation. I synthesise that the honeybee system is our most informative natural experiment in showing that vectored pathogens are more virulent than directly transmitted counterparts. I also show that outbreaking human epidemics (Zika virus) can threaten apiculture – and by extension livelihoods and agriculture.Natural Environment Research Council (NERC
Curved Track Analysis of FSO Link for Ground-to-Train Communications
No full textIn this work, a free space optical (FSO) link for the ground-to-train (G2T-FSO) communications is proposed. Analytical analysis is carried out for the curved rail tracks. We show that the transmitter divergence angle, the transmit power and the size of the concentration lens need to increase for the curved section of the rail track compared to the straight track. We derive the analytical expression for the received power level based on the link geometry for the case of the curved track In the worst case scenario when the curvature radius is 120 m, the transmit power at the optical base station (BS) needs to increase by over 2 dB when the concentration lens radius is increased by 5 times. Analyses also show that the received power along the track increases with the curvature radius for the same transmit power and receiver optics illustrating the effect due to link geometry. Additionally, the signal-to-noise ratio (SNR) and the bit error rate (BER) performance of the system for the curved track with different curvature radii is analysed at data rates of 10 Mbps and 100 Mbps for an additive white Gaussian noise (AWGN) channel showing a good agreement between the theoretical and the simulated BER. Finally, effect of scintillations on the G2T-FSO link performance is discussed
Phosphate Recovery From Sewage Sludge Containing Iron Phosphate
No full textThe scope of this thesis was to lay the basis for a phosphate recovery technology that can be applied on sewage sludge containing iron phosphate. Such a technology should come with minimal changes to the existing sludge treatment configuration while keeping the use of chemicals or energy as small as possible. The research focused on understanding the exact mechanism for phosphate release from iron in sewage sludge in order to find a method to release phosphate in an elegant way. Phosphate is an essential nutrient for plant growth, but at the same time the resources of phosphate are limited and concentrated in a few countries outside Europe. Recovery of phosphate can secure the access to phosphate for food production and is therefore an important topic. Iron based phosphate removal is still used by a majority of sewage treatment plants (STPs) but no viable technology is available to recover phosphate from sludge without sludge incineration. The addition of iron is a convenient way for removing phosphate from wastewater, but this is often considered to limit phosphate recovery. Struvite precipitation is currently used to recover phosphate, and this approach has attracted much interest. However, it requires the use of enhanced biological phosphate removal (EBPR). Phosphate removal relying solely on EBPR is not yet widely applied and the recovery potential is low (<50%). Other phosphate recovery methods, including sludge application to agricultural land or recovering phosphate from sludge ash, also have limitations. Energy-producing STPs increasingly rely on phosphate removal using iron, but the problem (as in current processes) is the subsequent recovery of phosphate from the iron. In contrast, phosphate is efficiently mobilized from iron by natural processes in sediments and soils. Iron–phosphate chemistry is diverse, and many parameters influence the binding and release of phosphate, including redox conditions, pH, presence of organic substances, and particle morphology. The current poor understanding of iron and phosphate chemistry in sewage systems is preventing processes being developed to recover phosphate from iron–phosphate rich wastes like municipal wastewater sludge. In the first chapter parameters that affect phosphate recovery were reviewed, and methods are suggested for manipulating iron–phosphate chemistry in wastewater treatment processes to allow phosphate to be recovered. Iron is omnipresent in STPs. It can be present unintentionally, for e.g. due to groundwater seepage into sewers, or it is intentionally added for odour and corrosion control, phosphate removal or prevention of hydrogen sulphide emissions into the biogas. The strong affinity of iron to phosphate has advantages for efficient removal of phosphate from sewage but it may also reduce recovery efficiencies in struvite precipitation technologies or for some phosphate recovery methods from ash. On the other hand iron may also have positive effects on phosphate recovery. Acid consumption was reported to be lower when leaching phosphate from sewage sludge ash with higher iron content. Also, phosphate recovery efficiencies may be higher if an iron phosphate compound, like vivianite, Fe(II)3(PO4)2x8H2O, could be harvested from sewage sludge. Developers of phosphate recovery technologies should be aware of the potential and obstacles the iron and phosphate chemistry bears. The mineral vivianite, is already present in digested sewage sludge and can be an alternative phosphate recovery option to current technologies. To evaluate this, surplus and digested sewage sludge was sampled from full-scale STPs and analysed using XRD, (e)SEM-EDX and Mössbauer spectroscopy. Vivianite was observed in all plants where iron was used for phosphate removal. In surplus sludge before the anaerobic digestion ferrous iron dominated the iron pool (≥50%). XRD and Mössbauer spectroscopy showed no clear correlation between vivianite bound phosphate versus the iron content in surplus sludge. In digested sludge, ferrous iron was the dominant iron form (>85%). Phosphate bound in vivianite increased with the iron content of the digested sludge but levelled off at high iron levels. 70-90% of all phosphate was bound in vivianite in the sludge with the highest iron content (molar Fe:P = 2.5). The quantification of vivianite was difficult and bears some uncertainty probably because of the presence of impure vivianite as indicated by SEM-EDX. eSEM-EDX indicates that the vivianite occurs as relatively small (20 -100 µm) but free particles that could potentially be separated from the sludge. We hypothesize that chemical/microbial Fe(III) reduction is relatively quick and triggers vivianite formation in the treatment lines. Once formed, vivianite may endure oxygenated treatment zones due to slow oxidation kinetics and due to oxygen diffusion limitations into sludge flocs. It was shown that vivianite can indeed form relatively quickly in activated sludge systems. Kinetics of iron reduction, the microbial community and the mechanism of vivianite formation in activated sludge from two STPs were studied; one STP with a low iron dosing (STP Leeuwarden, EBPR) and the other STP with a high iron dosing (STP Cologne, applying chemical phosphorous removal, CPR) were studied. The sludges were incubated under anaerobic conditions in batch experiments. The iron reduction rate in the CPR sludge (2.99 mg-Fe g VS-1 h-1) was 3 times higher than the rate observed in the EBPR sludge (1.02 mg-Fe g VS-1 h-1). The higher iron reduction rate in the CPR sludge is probably caused by its 3 times higher iron content. The rate constants (k) in both sludges are comparable (0.06 h-1 in EBPR sludge vs 0.05 h-1 in CPR sludge), thus the potential rates in both sludges are similar. For calculating the time it takes to turn over all Fe(III) to Fe(II) in the sludge, the Fe(III) reduction rates at the total ferric iron content of the experiments were used and assumed to be constant over time. Calculations then suggest that all iron in STP Leeuwarden and STP Cologne can be turned over within 15 h and 44 h respectively. Sequencing showed that both of the sludges were dominated by proteobacteria (65 – 89% of all operational taxonomic units, OTUs) and that the dominant class of bacteria were β-proteobacteria (38-63% of all OTUs). The microbial communities in both sludges contained genera that comprise iron oxidizing and iron reducing bacteria. These genera were more abundant in the CPR sludge with a higher iron content. XRD and Mössbauer spectroscopy showed that significant quantities of vivianite were formed in the sludges within 24 h. Our study suggests that iron metabolizing bacteria are more abundant in sludge which is rich in iron and that significant vivianite formation can already take place before the anaerobic digestion process. Based on the findings, vivianite is the most important phosphate phase provided enough iron is present, vivianite separation from sewage sludge was studied using a tailor made magnetic separator. Vivianite particles are paramagnetic and present as free particles. Magnetism is an elegant technology as it exclusively separates the liberated and paramagnetic vivianite (and perhaps some pyrite or iron carbonates that are present in the sludge). For this purpose a magnetic separator with Jones magnetic plates was designed and tested on two digested sewage sludges with different iron content. Varying feeding rates were used for the separation. A higher phosphate separation efficiency was achieved with sludge that contained more iron (up to 60% of all input phosphate was recovered) compared to the sludge with lower iron contents (up to 40% of all phosphate could be recovered). The iron and phosphate content was double sometimes even three times higher in the separated (magnetic) fraction when compared to the initial sludge solids. The crystalline fraction of the separated material consisted mainly of vivianite (68%) but also quartz was found (32%) as shown by XRD. The separated material had still a relatively high volatile solid content ranging between 30 – 40% of the dry matter. This fraction is related to organic compounds and other compounds that lose weight during heating (such as carbonates or vivianite). Based on these observations a new phosphate recovery technology for vivianite containing sludge was proposed that makes use of relatively cheap magnetic separation equipment from the mining industry. In this process iron is dosed in high quantities during the treatment process. This would result not only in low effluent phosphate concentrations but, additionally, vivianite formation is not limited by iron during the anaerobic digestion and this would probably result in the transformation of all available phosphate to vivianite. Then vivianite can be separated using a magnetic separator. This separation could be combined with a liberation or pre-separation step by using e.g. a hydrocyclone. Once vivianite is separated from sludge it could be directly used, preferably to produce high valuable products, or it could be dissolved to produce fertilizer. Pure vivianite can easily be dissolved at alkaline pH of about 12. At this pH, phosphate goes in solution and iron and most other metals remain in the precipitate. The phosphate solution obtained from the separated vivianite can directly be used for fertilizer production. Iron could be re-used for phosphate elimination in the STP. In another study it was tested whether sulphide can help to release and recover phosphate from sewage sludge. A series of batch experiments were conducted on different synthetic iron phosphates: Fe(III)P purchased from Sigma, Fe(III)P synthesized in the lab and vivianite. Sulphide was added to these different iron phosphates in a molar Fe:S ratio of 1 to evaluate the total phosphate release and the kinetics of phosphate release into solution. Phosphate release was usually completed within 1 hour. The maximum phosphate release was 92%, 60% and 76% from vivianite, Sigma Fe(III)P and Fe(III)P synthesized in the lab, respectively. However, rebinding of the released phosphate by Fe(II), only in the experiment with Fe(III)P that was synthesized in the lab, reduced the net phosphate release to about 56%. Sulphide induced phosphate release from vivianite is more efficient because sulphide reacts directly with Fe(II) to form FeSx and releases phosphate. No additional sulphide is needed for reducing Fe(III) to Fe(II). At the same time Fe(II) in vivianite is probably more efficient, or as efficient, as Fe(III) in retaining phosphate. Phosphate release from Fe(III)P was, at its maximum (before re-sorption/re-precipitation of the phosphate to other compounds in the sludge) higher than stoichiometry would suggest. Probably because sulphide was acting as a reducing agent, without significant formation of FeSx. FeSx formation requires a larger sulphide input. The high efficiency (moles P released / moles S input) of sulphide acting as a reducing agent to release phosphate was confirmed in additional experiments where sulphide was slowly added to Fe(III)P. Moreover, sulphide addition experiments showed that up to 30% of all phosphate could be released from digested sewage sludge. The highest phosphate release was achieved in experiments with the highest iron content. The total phosphate release from digested sludge was not as high as expected, earlier measurements using XRD and Mössbauer spectroscopy, that were used to quantify iron bound phosphate in the digested sludges, suggested that more phosphate should be iron bound and hence sulphide extractable. The dewaterability (determined using capillary suction test) in digested sludge (0.13 ±0.015 g2(s2 m4)-1) dropped significantly after sulphide was added (0.06 ±0.004 g2(s2 m4)-1). This strongly suggests that sulphide addition to sewage sludge will result in higher sludge disposal costs. Only insignificant phosphate release (1.5%) was observed from sewage sludge ash in response to sulphide addition. Overall, sulphide showed to be a useful tool to release phosphate bound to iron from sewage sludge for its subsequent recovery. Drawbacks are the deterioration of the sludge dewaterability and a net phosphate release that is lower than expected. In a side project of this thesis biogenic iron oxides (BioFeO) formed by Leptothrix sp. and Gallionella sp. were compared with chemically formed iron oxides (ChFeO) for their suitability to remove and recover phosphate from solutions. The ChFeO used for comparison included a commercial iron based adsorbent (GEH®) and chemical precipitates. Despite contrary observations in earlier studies, our batch experiments showed that BioFeO do not have superior phosphate adsorption capacities compared to ChFeO. However, it seems multiple mechanisms are involved in phosphate removal by BioFeO which make their overall phosphate removal capacity higher than that of ChFeO. The overall phosphate removal capacity of Leptothrix sp. was 26.3 mg P/g dry matter (d.m.), of which less than 6.4 mg P/g d.m. was attributed to adsorption. The main removal is likely due to formation of organic iron phosphate complexes (19.6 mg P/g d.m.). Gallionella sp. had an overall phosphate removal capacity of 39.6 mg P/g d.m. Significant amounts of phosphate were apparently incorporated into the Gallionella sp. stalks during their growth (31.0 mg P/g d.m.) and only one fourth of the total phosphate removal can be related to adsorption (8.6 mg P/g d.m.). Their overall ability to immobilize large quantities of phosphate from solutions indicates that BioFeO could play an important role in environmental and engineered systems for removal of contaminants such as phosphate or arsenic. This thesis showed that the iron phosphate chemistry in STPs has been neglected in the past and that more research is necessary to understand the complex interactions between iron and phosphate. This knowledge would help to improve the use of iron in STPs for phosphate removal further and pave the way for new phosphate recovery technologies from iron rich sewage sludge. Within the framework of this research the mineral vivianite was identified as a main iron phosphate phase in sewage sludge. Phosphate recovery technologies via vivianite might lead to a significantly higher recovery efficiency compared to routes relying on struvite. Magnetic separation of vivianite from sewage sludge was achieved using equipment from the mining industry. This process will be tested on pilot scale next. Future research related to vivianite based phosphate recovery has to focus on (I) understanding the formation of vivianite in STPs, (II) improving the separation efficiency of vivianite from sewage sludge using equipment that is tailor made for the type of vivianite which is contained in the sludge (density, magnetic susceptibility etc.) or by manipulating the formation of vivianite (by e.g. increasing its particle size) and (III) evaluating the purity of vivianite in sewage sludge to determine its economic value.BT/Environmental Biotechnolog
Parasite Insight: Apicystis bombi Prevalence of the under-reported parasite Apicystis bombi across natural barriers and life stages in pollinator hosts.
No full textAnnually, bees contribute over US$298 billion to the world economy, mostly through their ecosystem service of pollination. Several anthropogenic effects are reducing global wild and managed bee species populations, such as climate change and agricultural land use. There is an urgent need to fully understand the causes of these declines in order to find lasting solutions. One important factor in these declines caused by these anthropogenic effects may be emerging bee pathogens. Bee pathogens can easily jump when transmitted oral-fecally between species due to shared food resources and the commercial movement of honeybee and bumblebee hives. Bees typically have less resistance to emerging pathogens which they have not evolved alongside of, compared to established pathogens, potentially making emerging pathogens a major contributor to bee declines. This thesis studies the spread of the largely under-researched neogregarine parasite Apicystis bombi, which has been shown to have lethal and sub-lethal effects on bumblebees. Island biogeography predicts that islands have a lower prevalence of pathogens compared to nearby mainland. Chapter 2 compares the prevalence of A. bombi in the UK and France across island and mainland sites in foragers of two bumblebee species, Bombus terrestris and Bombus pascuorum, and the honeybee, Apis mellifera. The island prevalence of A. bombi in B. terrestris (41%±3 s.e.) and B. pascuorum (30%±3) was significantly lower than nearby mainland sites (65%±7 and 65%±9), despite having similar climates. This suggests that natural barriers significantly slows the spread of pathogens. However, in A. mellifera the island prevalence (65%±5) of A. bombi was as high as the mainland prevalence (63%±5). A possible explanation is that the commercial transportation of honeybees bypasses natural barriers, spreading pathogens. The distribution of A. bombi in A. mellifera hives has never been reported before. Chapter 3 investigates the prevalence of A. bombi across A. mellifera capped larvae, nurses and foragers. All three life stages contained A. bombi, although larvae (59%±10) and foragers (63%±15) had a significantly higher prevalence than nurses (23%±12), confirming that A. bombi can be spread throughout the hive either by contaminated pollen or faeces. The A. bombi prevalences found here are much higher than previously reported, in both A. mellifera and Bombus species. Such high prevalence is cause for concern, and could be a contributing factor in global bee declines
Integrated resource recovery from aerobic granular sludge plants
No full textThe study evaluated the combined phosphorus, nitrogen, methane, and extracellular polymeric substances (EPS) recovery from aerobic granular sludge (AGS) wastewater treatment plants. About 30% of sludge organics are recovered as EPS and 25–30% as methane (≈260 ml methane/g VS) by integrating alkaline anaerobic digestion (AD). It was shown that 20% of excess sludge total phosphorus (TP) ends in the EPS. Further, 20–30% ends in an acidic liquid waste stream (≈600 mg PO4-P/L), and 15% in the AD centrate (≈800 mg PO4-P/L) as ortho-phosphates in both streams and is recoverable via chemical precipitation. 30% of sludge total nitrogen (TN) is recovered as organic nitrogen in the EPS. Ammonium recovery from the alkaline high-temperature liquid stream is attractive, but it is not feasible for existing large-scale technologies because of low ammonium concentration. However, ammonium concentration in the AD centrate was calculated to be 2600 mg NH4-N/L – and ≈20% of TN, making it feasible for recovery. The methodology used in this study consisted of three main steps. The first step was to develop a laboratory protocol mimicking demonstration-scale EPS extraction conditions. The second step was to establish mass balances over the EPS extraction process on laboratory and demonstration scales within a full-scale AGS WWTP. Finally, the feasibility of resource recovery was evaluated based on concentrations, loads, and integration of existing technologies for resource recovery.</p
Genetic diversity and structure in European bumblebee (Bombus spp.) populations.
No full textIn recent years there has been a global trend in declines of pollinator species primarily due to anthropogenic stressors, including habitat fragmentation and land-use change resulting from agricultural intensification. The subsequent loss of foraging plants via this process creates habitat ‘islands’, causing genetic isolation similar to that found on geographic islands. Isolated populations are at a much greater risk of inbreeding and reduced genetic diversity, which in turn increases their susceptibility to disease. To reduce the fragmentation of wildlife populations, the EU introduced Agri-environmental schemes (AES) which provide mitigation methods including offers of financial aid to farmers planting wild flower margins. This thesis compared two wild bumblebee species between island and mainland sites in the UK and France to assess the impact of geographic isolation on populations. This thesis also sampled four bumblebee species in sites with different levels of AES in the UK, to assess the efficacy of the schemes in terms of promoting genetic diversity and analyse relationships between heterozygosity and disease. By using genetic techniques to estimate the diversity, structuring and population size of each species, comparisons between different environment types were made. Molecular analysis found significant structuring in Bombus pascuorum (θ = 0.122) populations across the UK and French populations. Within B. pascuorum populations, there was found to be a higher prevalence of the gut trypanosome Crithidia bombi in populations with reduced heterozygosity. Molecular analysis of the agri-environmental sites found a positive relationship between floral diversity and the heterozygosity of the population, and a large proportion of genetically similar sister pairs were sampled within these sites. 4 The overall conclusions from the research presented in this thesis are that to sustain wild pollinator numbers, further development of agri-environmental schemes is required with a focus on increasing floral diversity. Even with low intensive sampling effort sister pairs are likely, which can impact the results of epidemiological studies of haplodiploid species. Furthermore, the genetic analysis presented here suggests a strong link between population isolation and disease prevalence, thus isolated populations are at greater risk of extinction unless intervention occurs
Trypanosomatids are common and diverse parasites of Drosophila
No full textDrosophila melanogaster is an important model system of immunity and parasite resistance, yet most studies use parasites that do not naturally infect this organism. We have studied trypanosomatids in natural populations to assess the prevalence and diversity of these gut parasites. We collected several species of Drosophila from Europe and surveyed them for trypanosomatids using conserved primers for two genes. We have used the conserved GAPDH sequence to construct a phylogenetic tree and the highly variable spliced leader RNA to assay genetic diversity. All 5 of the species that we examined were infected, and the average prevalence ranged from 1 to 6%. There are several different groups of trypanosomatids, related to other monoxenous Trypanosomatidae. These may represent new trypanosomatid species and were found in different species of European Drosophila from different geographical locations. The detection of a little studied natural pathogen in D. melanogaster and related species provides new opportunities for research into both the Drosophila immune response and the evolution of hosts and parasites.</p
Phosphorus recovery from iron-coagulated sewage sludge
No full textFertilizers are vital for our society since we use them to grow plants. These plants can produce fruits and vegetables that we can consume or use as feedstock for the animals, ending up in our plates. In short, we need fertilizers to make our food, and we are using an increasing quantity of it with the growing population. Phosphorus is an essential constituent of fertilizers and a critical element for every living organism since it is present in DNA and bones. The current approach is to mine phosphate rock to make fertilizer. This strategy is the only option we have so far to produce phosphorus in large quantities, but it is polluting, and the resources are not endless. In our society, we are trying to replace fossil energies with renewable energy. However, this cannot be done for phosphorus; nothing can substitute it. Therefore, we need to find alternatives to obtain phosphorus without further damaging the planet...BT/Environmental Biotechnolog
- …
