Thursday, February 28, 2019

How Do Trees Fare in Major Cyclones / Hurricanes?

If you are in those areas both a little north and south of the equator you probably experience major tropical storms variously called cyclones, hurricanes or typhoons, depending on where you are located.

In Australia we get cyclones while in the USA they are named hurricanes, and typhoons in much of East Asia.  All are powerful, destructive storms and it seems, getting stronger.

Loss of the local vegetation is common - with lots of leaves shredded as an initial effect of the wind damage and often massive loss of tree cover, plus broken branches and destroyed and fallen trees.

The question is asked.....how do trees cope in these massive storms?  What happens to them, and why are some much better survivors?  Following Cyclone Marcus in 2018, the Darwin local government council, no stranger to these massive storms, sought to try and detail what trees fared best and why and to develop an improved list of suitable resilient trees, and to detail those of  much lesser stability and resilience.  Earlier work detailed outcomes of the major Cyclone Tracy in December 1974 in relation to tree resilience.

More recently, the February 2019 edition of The Scientist journal has explored this much more, even experimenting with "pseudo hurricane" damage to explore redevelopment of natural forest cover.

explore the link - some good graphics and information as well.  Hyper link below.

https://www.the-scientist.com/features/how-trees-fare-in-big-hurricanes-65335 

Friday, February 22, 2019

Soil Moisture Monitoring by Drone

Australian stuff from Monash University.  Very neat and very useful.


Autonomous Drones for Soil Moisture Mapping Help Farmers Use Water More Efficiently (Video)

Monash ​University ​engineers are ​working with ​Australian ​farmers to help ​them improve ​irrigation ​practices, ​reduce water ​use and ​maximise crop ​harvest by ​using ​autonomous ​drone ​technology. ​
As severe ​drought ​continues to ​devastate ​farmland and ​impact food ​supply across ​Australia, a ​Monash ​University ​research team, ​led by ​Professor Jeff ​Walker, has ​spent the past ​two years ​developing a ​drone-based ​autonomous soil ​moisture ​mapping system ​for irrigated ​paddocks. ​
5t5GBkm.jpg
Monash ​University ​engineers are ​working with ​Australian ​farmers to help ​them improve ​irrigation ​practices by ​using ​autonomous ​drone ​technology. (​Image source: ​Monash )
The team has ​recently ​completed field ​experiments ​using optical ​mapping which ​can determine ​soil moisture ​levels in the ​near-surface. ​The data taken ​from the drone ​can be ​downloaded and ​used to produce ​a map of ground ​soil moisture ​levels to ​inform the ​farmer on how ​best to ​irrigate the ​paddock. ​
While equipped ​with optical ​mapping as a ​proof-of-​concept, the ​drone has now ​advanced to ​passive ​microwave ​sensing ​technology ​using L-Band ​waves, with ​further ​research being ​conducted on ​the potential ​for using P-​band waves. P-​Band waves are ​expected to be ​able to measure ​up to 15cm into ​the soil ​unimpeded by ​vegetation and ​tillage ​features. ​
Drones have ​the capacity to ​analyse soil ​moisture at ​metre-level ​scales within a ​paddock, ​allowing ​farmers to ​focus on ​specific crop ​irrigation, and ​overcomes the ​challenges of ​aircraft or ​satellite ​mapping. ​
Testing has ​taken place ​across two ​farms in ​regional ​Victoria and ​Tasmania. One ​was at a dairy ​farm using a ​centre pivot ​irrigator and ​the other was a ​crop farm using ​a linear shift ​irrigator. ​
“We need ​to produce 60% ​more food with ​the same amount ​of land and ​water, and we ​can only ​achieve this by ​being more ​efficient with ​the water we ​use through ​irrigation,​” ​Professor ​Walker, Head of ​Civil ​Engineering at ​Monash ​University, ​said. ​
“We need ​to know how ​much the crop ​needs, how much ​moisture is ​already there ​and apply just ​the right ​amounts of ​water in the ​correct places ​to avoid ​wastage while ​keeping the ​crop at its ​peak growth.​” ​
Good soil ​moisture allows ​for the optimal ​growth and ​yield of crops, ​while at ​broader spatial ​scales also ​regulates ​weather, ​climate and ​flooding. The ​water levels in ​the soil ​controls ​evaporation ​over land and ​thus the energy ​fluxes into the ​atmosphere. ​This drives the ​atmospheric ​circulation, ​which drives ​climate. ​
“If the ​soil is too dry,​ crops can fail ​due to a lack ​of water. But ​if the soil is ​too wet, crops ​can not only ​fail but pests ​and diseases ​can flourish,​” ​Professor ​Walker said. ​
Professor ​Walker said the ​farming ​industry has ​welcomed ​smarter and ​more automated ​practices, but ​there are few ​tools available ​to make the ​already ​difficult ​workloads of ​farmers more ​manageable. ​
“At best,​ farmers might ​have a single ​soil moisture ​sensor in a ​paddock, but ​this doesn’​t allow for the ​optimal ​application of ​water, ​especially as ​this resource ​becomes scarcer.​ Plus it ​won’t ​take into ​account ​moisture ​variation ​levels across ​the individual ​paddocks,”​ Professor ​Walker said. ​
As crop ​failures due to ​a lack of water ​have enormous ​human and ​financial ​consequences, ​Professor ​Walker said ​Australian ​farmers need to ​become more ​efficient in ​soil moisture ​mapping by ​using ‘​precision ​agriculture’​ methods such ​as autonomous ​soil moisture ​mapping using ​drones. ​
“Farmers ​also need to ​cooperate; ​water ​conservation ​and efficiency ​is a collective ​responsibility. ​Everyone needs ​to do their ​part to use ​water more ​effectively or ​we’re at ​risk of running ​out completely,​” ​Professor ​Walker said. ​
“As the ​world’s ​driest ​continent ​facing climate ​change, a ​growing ​population and ​a greater ​demand for food,​ water ​conservation ​should be one ​of Australia’​s top ​priorities.​” ​
This project ​is part of ​Monash ​University’​s expanding ​interdisciplinary​ ​focus on the ​use of data and ​technology to ​solve real-​world problems ​for today and ​in the future. ​
The Autonomous ​Drones for Soil ​Moisture ​Mapping project ​was funded by ​Monash ​Infrastructure ​through a seed ​funding scheme. ​This project ​forms part of ​Professor ​Walker’s ​wider research ​into soil ​moisture ​mapping and ​autonomous ​farming.  ​
News source: Monash University  
Video source:​ Posterboy ​Media on Vimeo 

To download, click ‘Download’ button on the right (on a computer) and download ‘Original’ format - this is the best format for redistribution…

Thursday, February 21, 2019

Sulfate Boosts Ability of Plants to Handle Dry Conditions

Plants absorb the mineral sulfate from soil water. An international research team led by scientists from Heidelberg University has uncovered how sulfate controls the production of the drought stress hormone ABA in plants and thus contributes to their drought-resistance. These findings improve scientists' understanding of how the drought-stress signal travels from the roots to the leaves. The studies in Heidelberg were carried out at the Centre for Organismal Studies (COS).
Plants take in carbon dioxide for photosynthesis through pores in their leaves. When rainfall is low, however, these openings spell disaster for the plants because strong sunlight and active photosynthesis draw a lot of water through the open pores. Without fresh water from the roots, the plants wither and ultimately die. The hormone ABA [abscisic acid] controls how far the pores open in order to regulate the water loss of the plant.
Last year the researchers uncovered that the nutrient sulfate accumulates in the water transport pathways of the plants when the soil begins to dry out. Now the team led by Dr Markus Wirtz and Prof. Dr RĂ¼diger Hell has shown that the mineral actually known as sulfate plays a critical signalling role in supplying water to the plant. “Even we were surprised how efficiently sulfate triggers the synthesis of ABA and thus controls closure of the pores,” states Prof. Hell.
“The extremely dry European summer of 2018 was a preview of the imminent effects of global warming on the growth of plants and nutrient production,” stresses Dr Wirtz. “To be able to cultivate food crops that are more resilient during periods of water scarcity and drought, we need to understand how environmental factors regulate the formation of the hormone ABA”.
The results of the study were published in the journals “The Plant Cell” and “Plant Physiology” in late 2018.
The implications for turf could be most intriguing too and if your also add in the known effects of potassium on cell wall strengthening under dry conditions, could this explain or partially suggest an improved role for use of potassium sulfate as a summer fertiliser, or use of more complex mixes including slow release nitrogen?
Potassium sulfate is an often favoured means of supplying potassium and considered much superior to some alternate and cheaper forms, but is the real benefit the potassium or the sulfate in boosting drought resilience in many summer growing warm season turf grasses, especially in water deficit and /or hot stress conditions?  Do similar issues arise if using potassium sulfate in hydroponics in hot conditions [ it is commonly used in hydroponic cultivation] ?
It is an intriguing outcome of the research.......with no doubt more to come.

[ some material used from a press release by COS]


Wednesday, February 20, 2019

SURPRISE - the Earth is Getting Greener!!


It seems there is always doom and gloom environment news - so here is some good news, as reported by CNN.

NASA satellite imagery reveals that China and India are leading the world in adding volumes of green foliage. 

Also, since 2000, the Earth's overall green acreage has grown by 5%, an area equivalent to the Amazon's rainforests.

So.......maybe some positive news.

Monday, February 04, 2019

Banana Streak Disease May be Disabled

Bananas continue to be a target plant for breeding using new technologies.

The latest is a development that eliminates banana streak virus disease from the plant as well as preventing reinfection, using various gene editing options.  This disease is a major problem in parts of west Africa.

Read the full story here - https://www.newscientist.com/article/2192461-virus-lurking-inside-banana-genome-has-been-destroyed-with-crispr/

Developments like this continue to be implemented and offer significant potential for food crops especially in areas where some crops are staple foods.......and lowered production can be devasting to the local population.

Yes, there are some scientific and policy issues to be considered but there seems to be a better understanding that maybe these approaches with genetic engineering [as a broad approach] offer a real way forward in better plant production.

We are likely to see expanded use of the CRISPR gene technology across many crops or even less well developed or unexploited species to develop newer varieties for modern agriculture and improve overall crop productivity.