The phrase "a main natural" is not correct and does not convey a clear meaning in written English.
It may be intended to describe something that is a primary or significant natural element, but the phrasing is awkward and unclear.
Example: "The forest is a main natural resource for the local community."
Alternatives: "a primary natural" or "a key natural".
One female disappeared the night after release and was probably taken by a fox, the main natural predator of geese at the study site.
Baicalein is a flavone and the main natural resource for this compound is the roots of Scutellaria baicalensis a traditional Chinese medicine with different biological activities including antiviral activity [ 31].
The peninsula itself resembles a giant salmon – a fitting symmetry, given its main natural resource – fleeing southwards from the Russian mainland down towards Japan.
But for Florida, as for a growing number of American states, water is a perennial preoccupation and the main natural limitation to growth and development.
Tanshinone IIA (Tan IIA) is one of the main natural active ingredients purified from Salvia miltiorrhiza radix, which has long been used in clinical practice in China to treat diseases including liver fibrosis, Alzheimer׳s disease, and cardiovascular diseases.
Oil is Libya's main natural resource, with a pre-revolt output capacity of about 1.6m barrels per day, accounting for more than 95% of exports and 75% of the budget.
IS fighters reportedly captured the Jazal oilfield, a medium-sized field northwest of the IS-held ancient city of Palmyra, close to a region that holds Syria's main natural gas fields and multi-million-dollar extraction facilities.
The main natural factors in such a complex landscape system are water, topography, soil, geology, and climatic conditions, as well as plants (vegetation cover) and animals (fauna).
This documents that the main natural vector for rabies in Thailand (the dog) is a remaining threat.
