NEWS

Current Science Reports

Assessing Coral Bleaching Increasing ocean temperatures of entanglement,’ says Hina Khatoon, Sensing sea-surface temperature speed up development in fish. Wildlife Institute of India. How does this affect fish larvae dis- Fishing is a major occupation in The Malvan marine sanctuary in persal? nearby villages. The researchers Maharashtra is rich in corals. These Rohan Arthur, Nature Conservation found that the fishers were not aware colourful animals are indicators of Foundation, Mysuru collaborated with of fisheries regulations and proper marine ecosystem health. From 2014 researchers from Spain to find out. gear disposal. to 2019, Baban Ingole and team from The team sampled around 1500 ‘Ineffective regulations worsen the CSIR-NIO, Goa have been conducting individuals representing 9 common situation,’ says Sumit Kumar, Wildlife underwater surveys. Over the period, species in the Mediterranean Sea. To Institute of India, Uttarakhand. there was an alarming decline in coral understand early life traits – growth The economic condition of fishers colonies. rate, settlement size, hatching and prevents purchasing better gear. And settlement dates – they counted low quality gear deteriorates rapidly. growth rings in the otolith, a structure ‘With better environmental aware- in fish ears which produces growth ness and if fishing boards provide rings annually. better gear cheaper, the problem of How long the larvae stay near the plastic in the Ganga might shrink,’ surface before settling to the bottom says Aditi Dev. determines how far they disperse. DOI: 10.1016/j.scitotenv.2020.143305 The data helped the researchers predict how changes in temperature Microplastic Pollution affect larval stages from hatching to Macro pollution in Marina Beach Image: Kalyan De settlement and influence their ability Microplastics are less than 5 millime- Monitoring the condition of corals in to disperse. tres in size. We ingest around 30 such turbid seas is difficult and underwater Nearly all species showed a de- particles everyday through sea salt surveys require resources. So the cline in surface larval displacement alone. They cause nervous and repro- team decided to try satellite data for with increase in temperature. They ductive disorders, and even cancer. the purpose. Collaborating with re- grew quicker and settled down. We need to understand microplastic searchers from the Punjab Remote Reduced population dispersal and waste better to manage the menace. Sensing Centre and the Kuwait Insti- contraction of ranges may isolate fish Recently, researchers from Pachai- tute for Scientific Research, they populations. This can impact fisheries yappa’s College, Chennai, and Bhara- measured thermal stress on corals in and marine ecology and evolution, thidasan University, Tiruchirappalli the eastern Arabian Sea. say the researchers. collaborated with researchers from In 2015, sea-surface temperature DOI: 10.1111/1365-2656.13435 Japan and France to investigate rose to a record level. A 12-week microplastic waste from Marina beach, cumulative measure of thermal stress Ghost Gear in Ganga in Chennai. remained above threshold levels from Threat to biodiversity They processed samples from sea 2014 on, peaking in 2016. Ghost gear, discarded fishing equip- water, and wet and dry sand along a ‘When stressed, corals expel symbi- ment in water bodies, traps aquatic 5 kilometre stretch. There were 250 to otic microalgae. The algae provide animals. Ruchi Badola and team from 400 microplastic particles per kilogram nutrition and energy. Without them, the Wildlife Institute of India, Dehra- of sample. Under a microscope, most corals turn pale and die,’ explains dun set about identifying the sources microplastics were like filaments. Baban Ingole. of ghost gear in the Ganga, in col- Some were like granules. ‘Satellite sea surface temperature laboration with researchers from ‘The number of microplastics here is data is cost-effective to monitor coral Bangladesh and the UK. almost twice what is found in Mumbai, reefs and predict bleaching,’ adds his The team selected nine locations Tuticorin or Dhanuskodi beaches,’ colleague, Kalyan De. along the river, ranking them based says S. Venkataraman, Pachaiyappa’s DOI: 10.1080/10106049.2021.1886345 on gear density. Ghost gear in- College. creased in the river as it flowed to- The team found that most were Increasing Ocean Temperatures wards the Bay of Bengal – remnants polyester or polyfluoride compounds. Isolating marine assemblages of plastic nets, some with mesh sizes Polyester is a commonly used syn- Most marine fish have a biphasic life that are illegal. thetic textile and polyfluoride is used in cycle. They spend their early life as Air breathing aquatic animals are electric batteries, food processing and free swimming larvae near the surface, the most affected. packaging. Synthetic textiles, domestic dispersing through phytoplankton, and ‘Turtles, otters and the endangered water and fishing material are major settle to the bottom after maturity. Ganges river dolphin are at high risk sources of microfilament plastic.

CURRENT SCIENCE, VOL. 120, NO. 6, 25 MARCH 2021 975 NEWS

Banning plastic bags is not enough What is the long-term impact of biological and chemical oxygen de- to stem the microplastic menace. plantation forests on species composi- mand, making it inhospitable to aquatic DOI: 10.1016/j.scitotenv.2020.144073 tion, plant diversity and carbon storage life. potential? How do these differ from ‘Such conditions affect livelihoods. Wildlife Behaviour those in natural forests? The long-term impact might be irre- Temporal interaction Anudip Gogoi and colleagues from versible,’ adds Indrajit Mandal. the Mizoram University, Aizawl set out The report is a wake-up call to use Fear of predators drives temporal pat- to explore. The team used the same environment-friendly technologies for terns in prey. Chances of detecting sampling technique in a 39-year-old stone mining and crushing. prey determine carnivore activity. But plantation forest and a natural forest in DOI: 10.1080/10106049.2019.1597390 these patterns are not rigid. Subtle the Brahmaputra flood plains changes in niche regulate the ecosys- In the natural forest, species domi- tem. Indian King Prawn Farming nance and evenness were higher. As Urjit Bhatt and team from the Wildlife Loss due to infections were plant biomass and carbon stocks. Institute of India, Dehradun set up About 70% of export revenue from But, in the plantation forest, biodi- sensor-based cameras to document sea food is from the king prawn, Lito- versity indices were greater. Tree spe- animal activity patterns in Manas penaeus vannamei. However, dis- cies richness was slightly higher. The National Park, Assam. eases cause major losses for aqua number of herb species was three The team found that smaller carni- farmers in India. times higher. vores foraged at night, those of me- Recently, scientists from the ICAR- ‘Plantation forests reduce human dium-size were nocturnal or diurnal Central Institute of Brackishwater pressure on natural forests and create and large animals were active as and Aquaculture, Chennai, the Navsari livelihoods for associated communi- when they needed food or water. Agriculture University, Gujarat and ties,’ says Anudip Gogoi. ‘Body size seems to decide active the West Bengal University of Animal ‘Plant forests in degraded lands to periods,’ explains Urjit Bhatt, Wildlife and Fishery Sciences calculated the sequester carbon,’ suggests Jitendra Institute of India. economic impact of diseases in king Ahirwal, his colleague. How do related carnivores avoid prawn farming in India. ‘Sustainably manage such forests to conflict? By overlapping the temporal They conducted surveys in Tamil conserve biodiversity,’ recommends patterns of the animals, the research- Nadu, Andhra Pradesh, West Bengal, Uttam Kumar Sahoo. ers found that, though similar carni- Maharashtra and Gujarat, covering DOI: 10.1016/j.jenvman.2020.111671 vores hunt at the same time, they about 90% of the farming area. avoid competition in subtle ways. For To estimate employment loss due Stone Mining Deteriorates example, clouded leopards avoid to reduction in culture duration, the Dwarka river basin tigers by climbing trees. team interviewed more than 900 Besides day, night or twilight, lunar The Dwarka river basin in eastern shrimp farmers. phases also impact wildlife activity. India has huge reserves of building Economic loss for each farm was There was a strong correlation bet- stones. Stone mining and crushing are calculated based on selling price for ween moon phases and foraging. To common there. Recently, Swades Pal each size group. avoid predators and search for food, and Indrajit Mandal from the University Infection by Enterocytozoon hepa- smaller prey species are more active of Gour Banga, West Bengal exam- topenaei, a parasite, and white spot on brighter nights. But their predators, ined how these activities impact the syndrome virus accounted for most small carnivores, are active on darker environment. losses. Enterocytozoon hepatopenaei nights. Noise levels at mining and crushing infections caused an annual loss of ‘The risk of competition and preda- sites were almost a hundred decibels about 2700 crore rupees and the tion creates these temporal activity higher than safe for humans. From white spot syndrome virus, 1200 partitions,’ says Salvador Lyngdoh, satellite data, they discovered that sur- crores. Wildlife Institute of India. face temperature at the sites was up to The total loss is nearly 58,000 The behaviour of individual species three degrees higher than in peripheral crores due to these two diseases evolves to maximise survival. So, vari- areas. They found high levels of aero- when employment loss is also factored ous species coexist, maintaining a sols in the lower atmosphere. And in. Other diseases accounted for a delicate balance in forest ecosystems. vegetation health has deteriorated in a loss of about 500 crores annually. DOI: 10.1111/btp.12917 larger area. Soil in the area was highly Farmers are being trained to rec- alkaline and low in nutrients. Conse- ognise the symptoms of these dis- Restoring Biodiversity quently, crop yield was low. eases early to reduce losses. But Role of planted forests ‘Dispersed dust gathers on the river research on preventing and curing Some argue that plantation forests are bed. The river is now shallower by these diseases needs to be stepped threats to natural forests. Others de- almost half a metre,’ says Swades Pal. up to reduce the burden on farmers fend their role in biodiversity conserva- Water in the Dwarka river basin was and ensure sustained export revenue. tion. high in dissolved solids and had higher DOI: 10.1016/j.aquaculture.2020.736231

976 CURRENT SCIENCE, VOL. 120, NO. 6, 25 MARCH 2021 NEWS

Growing Lettuce S. K. Dingre and S. D. Gorantiwar physiological parameters for two Using hydroponics from the Mahatma Phule Krishi years. In monoculture, sunburn was Vidyapeeth, Maharashtra varied the more intense. Pineapple, they found, Cultivating lettuce in soil is challeng- water as per the needs at different performed better with a shade intensity ing. The crop is heat sensitive and stages of the crop. of about 50%. grows slowly. Though lettuce leaves ‘The growth stage, when the Intercropping mango with pineapple have high water content, lettuce sugarcane stem elongates, is most can improve the income of both mango water footprint is low. Can hydroponics critical. Adequate water at this stage and pineapple growers, say the re- help? can increase yield,’ explains S. K. searchers. In deep water hydroponics, roots Dingre, Mahatma Phule Krishi DOI: 10.1016/j.scienta.2020.109868 are suspended in a nutrient-rich solu- Vidyapeeth. tion. In nutrient film hydroponics, a ‘Restricting irrigation at germination Micro-Irrigation shallow stream of nutrient-rich water and maturity stages doesn’t affect crop Solar photovoltaic pump re-circulates through the roots. Which yield. In fact, we can reduce water method is better? use by 13 per cent,’ adds S. D. Goran- High horsepower photovoltaic pumps Recently, Maliqa Majid and her tiwar. dot landscapes in arid zones. This can team from the Sher-e-Kashmir Uni- The researchers hope that, in spell doom for meagre groundwater versity of Agricultural Sciences and Maharashtra, farmers will opti- resources. Priyabrata Santra from the Technology, Srinagar collaborated mize sugarcane yield using deficit irri- ICAR-Central Arid Zone Research with engineers from the Central Uni- gation. Institute, Jodhpur decided to innovate. versity of Kashmir and the Vaugh DOI: 10.1016/j.agwat.2020.106549 He tried micro-irrigation from surface Institute of Agricultural Engineering water using a one horsepower photo- and Technology, Uttar Pradesh to Effect of Shade Intensities voltaic pump. compare the methods. Intercropping mango and pineapple He set up solar panels, a pump unit They grew lettuce using both and a manual tracking system. In solar approaches. As control, they grew pumps, water discharge increases with some in poly-house tunnels, ideal for solar irradiance. But, in spite of varia- soil-based cultivation. tions in sunlight through the day and in Lettuce grew faster and yielded different seasons, his pump provided more in hydroponic systems. Deep adequate water. However, the dis- water culture reduced growing period charge reduced with increase in deli- by 16%. very head and the pump unit’s suction Hydroponically-grown lettuce had head. more total soluble solids, acidity and Priyabrata then used the interrela- chlorophyll, protein and crude fibre tions between the solar-pump’s head Image: Zainab37 via Wikimedia Commons content than lettuce from poly- and discharge to operate micro/mini tunnels. Mango monocrop orchards are a sprinklers and drippers. This optimised There was no significant difference common sight in the north and south of the distribution efficiency and water in water consumption between soil- India. The orchards spring into action discharge of the micro-irrigation sys- based and deep water culture. But from February till the monsoon tems. the nutrient film technique saved 64% drenches roots. And that is when the For uniform irrigation and maximum water. pineapple monoculture in the north- coverage, Priyabrata designed a web ‘Both approaches yield more and eastern states becomes active. of spatially distributed sprinklers and better lettuce. But the nutrient film Researchers from the ICAR-Indian drippers. The system could lift har- technique is better for water deficient Institute of Horticultural Research now vested runoff water in farm ponds with regions,’ says Maliqa Majid. suggest intercropping pineapple with minimum seepage and evaporation Hydroponics can help grow lettuce mango. Both regions may then benefit loss to irrigate crops according to and other crops profitably when there fruitfully. water requirement. is little or no access to soil. Kundan Kishore and colleagues When the pump is not operational, DOI: 10.1016/j.agwat.2020.106572 planted pineapples in four different electricity generated can be routed to light environments. A monoculture plot other purposes in the farm and for Irrigation Management acted as control. In the other three household demands, using circuit In sugarcane plots, they planted pineapples as inter- breakers, says the researcher. Sugarcane is a high water requiring crop in a low density mango plantation. The installation cost of solar pumps crop. But water scarcity in semiarid re- Mango canopies were pruned to pro- is more than that of electric and diesel gions makes growing sugarcane a vide low, moderate and high shade pumps. But the life cycle cost is low challenge. Irrigating the crop at critical intensities on pineapple plants. and such pumps reduce a farm’s car- growth phases can maximise produc- The team studied plant growth, bon footprint. tion under limited water resources. yield, nutrient content and other DOI: 10.1016/j.agwat.2020.106554

CURRENT SCIENCE, VOL. 120, NO. 6, 25 MARCH 2021 977 NEWS

Heart Health So, Hemalatha Karnan and Sivaku- Does spending more time on social A phone call away? maran Natarajan from NIT Trichy media and instant messaging influence developed a machine learning model scientific temper? High blood pressure is a silent killer, to ease the task. Sreeram Gopalkrishnan and Sne- predisposing people to cardiovascu- To train the model, they downloaded hal Galande from the Symbiosis Cen- lar diseases. Yet, many fail to keep 600 samples of electrocardiogram sig- tre for Media and Communication, blood pressure under control, miss nals from an arrhythmia database. Pune designed a questionnaire with follow-up appointments and do not ten statements based on recent adhere to medication schedules. claims of the superiority of ancient Can phone calls persuade patients Indian science in news and social to follow up? media and ten more based on super- As part of the Mumbai Hyperten- stitious cultural practices. The par- sion Project, researchers led by Kan- ticipants had to agree or disagree nure Mandar from the Program for with these statements. Appropriate Technology in Health Image: Ewingdo via Wikimedia Commons The duo administered the question- conducted a study in Mumbai slums. naire to 135 students from the same Previous studies showed that the They used a ranking selection algo- college, taking care to avoid students prevalence of hypertension is higher rithm to characterize relevant parts of they were teaching. The respondents in slums. the cardiogram signals. With support were 18 to 22-year-olds and repre- The team enrolled around 13,000 from Dr Rajajeyakumar Manivel, SRM sented 18 states and a wide variety of patients from 160 private clinics and Medical Hospital, Trichy, the research- mother tongues, but all accessed Eng- recorded their details and family his- ers marked the parts that signalled lish language media. tory of blood pressure. A treatment arrhythmia. They fed this information Based on their answers, the re- coordinator from the clinic made to the algorithm to focus only on useful searchers tried to gauge the students’ monthly or quarterly phone calls to subsets of the data. scientific temper. Scientific temper patients who missed appointments. To further filter the input, the team among this age group did not depend The coordinator reminded such needed an algorithm that clusters the on the subject studied, and use of so- patients to attend the follow up data. They used a support vector ma- cial media or instant messaging. But appointments, stressing the impor- chine, an algorithm, to create bounda- some students believed in supersti- tance of blood pressure control. ries between input points and to tions or mixed mythology with science Blood pressure control increased segregate them. in spite of urban environments, with from 25% to 49% in these patients. Finally, to extract the output, the good education and access to tech- But some patients did not answer the researchers took inspiration from nology. calls and some phones did not con- the pack hunting style of wolves. The ‘Most students are able to insulate nect. However, many who did not mean grey wolf algorithm is an itera- themselves from fake news coming via attend to the phone calls also visited tive process that converges on the WhatsApp and social media,’ says the clinics for follow up. Among best solution. Snehal Galande. these, blood pressure control in- The machine learning model can de- ‘The lack of difference between data creased from 22% to 44%. Statistical termine patterns between all the inputs from science students and non- analysis showed a linear relation be- and help clinicians detect arrhythmia science students shows that scientific tween the monthly or quarterly phone early. Now comes the bigger task – temper is about a way of thinking calls and blood pressure control in acceptance of the technology in clini- rather than knowledge of scientific the sample population. cal practice. theories and laws,’ says S. Gopal- These results can now be used by DOI: 10.1002/cpe.5001 krishnan, her colleague. the public health system to reduce DOI: 10.1007/s11422-020-10001-z cardiovascular diseases in the country. Scientific Temper in Colleges Insulating from fake news DOI: 10.1111/jch.14221 Reports by: Nadiya Manzoor, Ravi Scientific temper is influenced by poli- Mishra, Tejinder Singh Chechi, D. C. Machine Interprets Heartbeats tics, socio-economics, culture and Jhariya, Tahera Arjumand, Madiha Arrhythmia detection technology. All these have changed Qadri, Sileesh Mullasseri, Shwetak- The heart flutters when it sees a loved since the time the notion of scientific shi Mishra, Ishrat Nazir, Jauhar one. Most irregular heartbeats or temper was enshrined in the Constitu- Rafeeq, Pushp Sen Satyarthi, arrhythmias are harmless; however, tion of India. Manish Kumar Tekam, K. Sri Manjari some carry the risk of cardiac arrest. How has this impacted scientific Aradhana L. Hans and Khuban Buch The best way to diagnose arrhyth- temper among youngsters who have ACKNOWLEDGEMENT: IISER Pune for mia is using an electrocardiogram. But just reached voting age? Do students access to scientific databases. analysing heart signals is daunting and who study science have better scien- requires expertise. tific temper than those who do not? [email protected]

978 CURRENT SCIENCE, VOL. 120, NO. 6, 25 MARCH 2021