The paucity of mature tree cover in Malta, as well as the decline of mature trees in public places, are sacrosanct truths known to all. Official statistics show that about one per cent of the islands are covered by woodland, compared to the EU average is 35 per cent.
Of this one per cent, there are only a few remnants of natural or original woodland (that is, not planted by man); these are restricted to locations such as Il-Bosk in Buskett, l-Imġiebaħ in Mellieħa, Wardija and Ta’ Baldu in Dingli, which feature individual holm oak and Aleppo pine trees that are hundreds of years old.
Afforestation schemes have also been on the rise in recent years, contributing to a considerable surge in the amount of land covered by woodland, but these depend on a catalyst which, in most cases, is government or a private company.
We have become so surrounded by our urban environment that we scarcely realise that indigenous trees can be sown at the drop of a hat, even by individuals having little green acumen or garden space. In fact, acorns of the holm oak (Balluta) mature at this time of the year and these can easily be planted in compost, germinating into saplings sometime in spring.
Holm oaks are a slow-growing species, with Malta marking almost the southernmost extent of their range in the Mediterranean region, such that they can easily grow in sizeable pots until they are five years old, after which they need to be transplanted to an open-soil location, which could be a public garden in one’s own locality, if one lacks an appropriate location at home. The relative ease with which holm oaks can be propagated makes them an ideal candidate for tree nurseries in schools.
Arbor Day (International Tree Day) is due to be commemorated locally on Thursday. One way in which we can ensure that the spirit of Arbor Day truly lives on is by instilling a love for trees in children, and sowing the next generation of oak trees is one way of doing this.
ODZ barometer
From time to time in this column I take stock of current trends in the number of and locations where Outside Development Zone (ODZ) planning applications have been submitted to the Malta Environment and Planning Authority.
These trends have been summarised by using ODZ statistics for 13 predominantly rural localities in Malta, such as Mellieħa and Dingli, and all 14 Gozitan localities.
The number of ODZ applications Mepa received in 2011, 2012 and 2013 was 47, 235 and 70, respectively.
The Maltese locality with the highest number of ODZ applications received during the three years under review was Rabat (46), followed by Naxxar (which includes Magħtab – 26), Mellieħa (24), Siġġiewi and Mġarr (23 each), with the Gozitan counterparts being Xagħra and Sannat.
What should raise some eyebrows is the anomalously high percentage of ODZ applications that are submitted by a handful of architects, some of whom occupy prominent positions in Malta’s planning infrastructure.
In my next article I will focus on the most glaring of these ODZ applications.
Life under the sand
Sandy beaches (excluding sand dunes) do not rank high among conservation priorities, mainly as a result of the widespread misconception that these are essentially ecological deserts. In fact, up to the early 1980s, sandy beaches were mainly studied from a geological perspective, and marine biologists tended to regard estuaries, coral reefs and rocky shores, which are obviously teeming with life, as more fruitful areas for study than apparently impoverished sandy beaches.
The desert notion is further reinforced by the apparent lack of life on sandy beaches – besides the lack of attached plants, most macrofaunal (this is visible to the naked eye) species on sandy beaches burrow deep into the sand, emerging (if at all) at night and have a cryptic colouration.
Three recently-published scientific works on the ecology of Maltese sandy beaches, that the author co-authored and were partly funded by the University’s Research Fund Committee, shed more light on the vibrant world under the sand surface.
In the first study, a total of 25 Phaleria spp. (a beetle species restricted to sandy beaches) populations from sandy beaches on different central Mediterranean archipelagos (Maltese, Pelagian, Egadian, and Aeolian ones) and on the Sicilian mainland were sampled once, over the period March to October 2010.
P. acuminata populations from Ramla l-Ħamra and Xatt l-Aħmar and P. bimaculata populations from Għajn Tuffieħa, Golden Bay and Santa Marija Bay, Comino, were included in the study, with the two beetle species never being recorded together on the same beach. Heads and legs from a selected number of beetle individuals from each population were used for DNA extraction for genetic analyses.
The study also involved the use of the geometric morphometrics technique, which is nowadays a standard protocol in morphological research. Geometric morphometrics and molecular analyses gave identical results, allowing a sound separation of the two species.
In the second study, a total of 32 central Mediterranean sandy beaches in Malta, Sicily and various Sicilian islands were sampled for the presence of two Tylos species – Tylos europaeus and Tylos ponticus. The first species is known to live on just two beaches in Malta – Ramla l-Ħamra and San Blas in Gozo – while the second species is known to exist only in Paradise Bay.
The relative ease with which holm oaks can be propagated makes them an ideal candidate for tree nurseries in schools
The two species were never recorded on the same beach and, although T. europaeus has a preference for fine sand and T. ponticus has a preference for fine to medium sand, differences in the distribution of the two species could not be solely explained in terms of differences in sand particle size.
In the third study, the meiofaunal communities of local sandy beaches were described for the first time ever. Meiofauna consists of organisms that are smaller than 0.5mm and are thus too small to be seen with the naked eye.
A total of seven sandy beaches in Malta were sampled during spring 2012, with sediment samples being collected at the mean sea level. Median grain size and sand organic and water content were measured for each beach.
A total of 13 higher meiofaunal groups were recorded from the Maltese sandy beaches, with the most abundant groups being those of nematodes (roundworms), flatworms (turbellarians) and crustaceans (copepods), with other animal groups, such as water bears, which have never been fully studied locally, also being recorded. The meiofaunal abundance ranged between 50 and 1,392 ind/10cm2.
The meiofauna on Maltese sandy beaches separated by more than five to 10 kilometres were considerably different from each other, while Maltese sandy beaches showed comparable meiofaunal abundances compared to other central Mediterranean sandy beaches.
The three works have been published in the Journal of Crustacean Biology, Zoomorphology and Estuarine, Coastal and Shelf Science. They will eventually be available for download from the downloads section of the author’s website.
A robot buddy for divers?
Conmar, an Seventh Framework Programme-funded project, is seeking to develop a group of robots, in the form of autonomous surface vehicles, to supervise and guide divers along a prescribed path, thus effectively assisting them under challenging circumstances such as low underwater visibility. Divers would receive commands from the robots simply as patterns of lights from LEDs installed on their diving mask.
The offshore industry and marine scientists, among others, stand to benefit from this innovative navigation system as it brings them closer to cooperative human-robot missions at sea.
alan.deidun@gmail.com
www.alandeidun.eu