How salt is actually distributed

Salt on the coast doesn't end at a fixed point. It weakens along a gradient: closer to the ocean, aerosols and salty winds are effective; further away, barriers, topography, humidity, soil, and irrigation errors become more important.

Gradient, not a boundary

Salt moves through the air, water and the surface

A design error is to assume that the salt "runs out" at 300 meters. In reality, it decreases gradually. The intensity is affected by distance from the ocean, wind direction, humidity, topography, the presence of barriers, and the quality of irrigation water.

Marginal leaf burn indicates salt accumulation and water stress on the plant.

Coastal zoning shows how salt stress decreases from the ocean to the interior of the site.

Real gradation by distance

Distance from the shore	The influence of salt	What's happening	Design solution
0-30 m	extreme	only halophytes and barrier species survive	Atriplex, Tamarix, Salsola, sand fixation
30-100 m	very strong	the salty wind still damages the leaves	resistant shrubs and the first line of trees
100-300 m	average	You can build a system, but you need protection	second barrier, soil, drip irrigation
300-800 m	weak	conditions are closer to normal, but depend on the wind	fruit trees in protected areas
800 m+	minimum	almost normal soil with normal water	a wider choice of crops, but salt monitoring is needed

Three main routes of distribution

Path	How it works	Why is this important?
Marine aerosol	The wind carries salty microdroplets; the stronger the wind, the further they fly	the first line of leaves bears the brunt
Fog and humidity	moisture can be beneficial, but it also brings salts	fog helps the project only in conjunction with salt-tolerant species
Soil and evaporation	salt water rises, water evaporates, salt remains	a salt crust can appear even inside the area

Why does the barrier change distances?

If the area is exposed, salt aerosol can maintain a strong influence even over hundreds of meters. If there is a filtering barrier of shrubs and trees, the salt concentration drops sharply: the downwind zone receives less aerosol, the wind is weaker, and evaporation is lower.

What's important isn't a solid wall, but a filter belt. A wall that's too dense creates turbulence and flow rebound, while a living strip with moderate permeability dampens the wind more gently.

The filter barrier reduces wind speed and the transfer of salt aerosol.

Swale ditches and microrelief retain water to prevent salt from concentrating near the surface.

Fruit crops are placed behind a salt-resistant barrier, and not in the direct aerosol impact zone.

How to calculate the distance from the safety belt

In practical design, it's more convenient to calculate not only from the ocean but also from the height of the first defensive line. Let's denote the height of the belt as H. The protective effect is usually expressed in multiples of H: the zone of strong protection begins at approximately 1.5-2H, the comfort zone at 3-6H, and the distant protected zone at 6-10H.

Belt height	1.5-2H	3-6H	6-10H
3 m	4.5-6 m	9-18 m	18-30 m
4 m	6-8 m	12-24 m	24-40 m
5 m	7.5-10 m	15-30 m	30-50 m
6 m	9-12 m	18-36 m	36-60 m

What does this mean for fruit crops?

Group	Recommended area	Examples
The most resistant fruit	2-4H behind the first barrier with drip irrigation and closed soil	fig, pomegranate, jujube, prickly pear, date palm
Moderately sensitive	3-6H in a more secure leeward area	olive, grape, mulberry, carob, almond
Sensitive	5-8H, and for the most delicate ones 8-10H plus a second screen	citrus, mango, guava, papaya, avocado

Landmark from the coastline

Without a precise site, this is not a universal norm, but a starting design logic for the harsh Atlantic coast: the closer to the ocean, the more important salt aerosol, turbulence, and direct sea winds become.

Zone from the coastline	What to post
0-30 m	only salt-tolerant shrubs and barrier species
30-80 m	Tamarix, Casuarina, Atriplex, Salvadora, protective rows
80-150 m	fig, pomegranate, jujube, prickly pear, date
150-250 m	olive, grape, mulberry, carob
250 m+	citrus; next come mango and guava, given good soil and water

Practical conclusion for DREVO

The salt doesn't run out, it weakens. Therefore, it's necessary to design not a single planting line, but a gradient of zones: the first line absorbs the salt impact, the second reduces wind, the third builds the soil, and then fruiting and production elements are placed.

The biggest mistake is to count only horizontal distances. More important are the barrier height, planting density, prevailing wind direction, and the salinity of the irrigation water.