Maximum and minimum daily temperatures in Celsius (°C), precipitation in Milimeters (mm), and wind speed (km/h) for all sites have been mined and calculated on an online server Meteoblue (www.meteoblue.com).

Info graphical representation and comparison of the laboratory analysis between all three sites has been accomplished using Microsoft Excel.

Al Taween (Fig. 2) is located within the coordinates 25°34'15.14” N and 56°5'27.49”E in the UAE, with a perimeter, of 2,057.58 m, and a total area of 178,664 m².

The soil properties of each site have been analysed. The 10cm and 50cm soil layers does not show a significant difference (Table 1). The soil type in Al-Taween is alkaline, hence porous [17]. For soil layers 10 cm and 50 cm, the measured alkalinity is 258 and 211 mg/kg, respectively. It also shows very little conductivity, which estimates a less nutritional potential of the soil for plantation. There is an increase in conductivity with depth; 325 S/cm was measured in a 50 cm layer, compared to 171 S/cm in a 10 cm layer. Iron and potassium concentrations have been measured at 20 g/kg and 24 g/kg, respectively, which are higher than other components analysed. Molybdenum (Mo) is an essential trace element that plays a crucial function in the development and growth of plants. Symbiotic nitrogen-fixing bacteria in legumes require it to fix atmospheric nitrogen and convert nitrate into nitrite and then ammonia before using it to manufacture amino acids within the plant. However, larger concentrations are deemed harmful. Globally, the average Mo content in arable soils is between 1 and 2 mg kg [17, 18]. Mo levels range from 4.9 to 5.5 in the 10cm and 50cm soil layers+ in Al Taween (Table 1 and Fig. 3). The solubility of molybdenum increases as the pH of the soil becomes more acidic. As indicated by the results, the pH of the soil is approximately 9, making it alkaline and affecting the absorption of this element by plants. High Mo concentrations stem from two sources: high concentrations in soil due to parent materials and contamination from pollution, such as mining wastes. Apart from soil analysis, On-site visits determine the large gashes and gullies at different parts showing easily eroding soil. Such nature of soil makes it difficult for plant roots to soak up necessary nutrients. Acidifying fertilizers that contain elemental sulfur like aluminum sulfate or ammonium sulfate or organic fertilizers can be used to enhance soil fertility.

Fig. (2). A view of the Al Taween site with an approximate boundary determined by google.

Fig. (3). Soil elements contents analysis of ATF, Al Taween and FLAG park.

Fig. (4). Al Taween Maximum and minimum daily temperatures (˚C), precipitation (mm), and wind speed (km/h).

Data for 2021 and 2022 have been collected and analysed for temperature, precipitation, rainfall, and wind speed. During the months of May through August, temperatures in Al Taween typically rise to between 43 and 45 degrees Celsius on average (Fig. 4). The relative humidity decreased from April to June and remained above 60% throughout the year. Similarly, 30 mm of precipitation has been recorded for the month of January, with 50 mm being the highest recorded value for the month of August. The remainder of the year has observed little precipitation. Precipitation is one of the three major components of the global water cycle, with evaporation and condensation being the other two [19]. In addition, the average wind speed for this region during the first half of the year ranges between 14 and 20 kilometres per hour, with the exception of January, when it consistently exceeds 25 kilometres per hour. Moreover, later in the year exhibited the highest wind velocity. The annual rainfall is recorded as 76.2 mm which can provide up to 160,000 m3 of water each year as per calculations. Over the course of 18 years, from 2003 to 2021, we have also determined the average monthly total rainfall (in millimetres) (Supplementary Materials 1). The average rainfall for the months of January, March, and December is 20 mm, 14 mm, and 13 mm, respectively.

Based on field visits and collected soil, temperature, windspeed, and average annual rainfall, the water retention, plan for afforestation is proposed here. The system, if done correctly, can be useful in planting hundreds of more trees within this Wadi for greening, and animal or bee feed. The suggested are the plantation of native trees, such that extra water irrigation can be cut off after a few months. This arid land can be made arable using some of the check dam structures deployed in the watershed area of the Wadi. The system structure will help retain water and reduce flood severity. This is intended as a prototype for a system that can be deployed throughout other wadis in Fujairah, and eventually the UAE. AL Taween is a small wadi – not long enough for springs to emerge, but it is enough to demonstrate the utility of the broader system and begin training a team on its design and construction. The current estimate is for 7 check dams in the upper wadi and five in the lower wadi. Two Spack lines can be built to grant heavy machinery access to the upper wadi, provide stone for earthworks, and emergency access for teams and machinery in case of flash floods. Overflow points of each check dam should be level with the floor of the preceding check dam.

Together these earthworks will create planting spaces for hundreds of trees but will also catalyze the natural regeneration of the wadi, as long as it is protected from grazing animals. The water runoff and keeping in mind the average 7.5 liter of water requirement per tree in UAE, the area can be made suitable to plant 3300 to 3800 native trees planted in the Wadi. The illustration of the introduction of dams and plantations afterward has been explained in Fig. (5).

Fig. (5). The Al Taween area view. Yellow boundary showed the wadi, magenta structures showed the sequence and placement of check dam’s structures, green plants showed the proposed plantation sequence. Zoomed in window display how the dams work will look after completion in dry weather.

Fig. (6). A view of the ATF site with an approximate boundary determined by google.

Construction should only occur when the risk of rainfall and flooding is low; having heavy equipment and personnel in wadis during the rainy season is a risk, and while the likelihood of being caught in a flash flood is low, the potential for severe damage or death, if someone is caught in one, is high. Once the system is operational, construction should occur during the dry season and planting should occur during the wet season. If building is to take place while there is a chance of precipitation, there must be a strategy for safeguarding both materials and personnel from flooding, as well as for rapid evacuation.

While it may seem difficult to bring the equipment to the top of the wadis first, doing so protects the investment and substantially decreases the chance of blowouts as the check dams fill with silt eroded by precipitation.

ATF studied site is located within the coordinates 25°8'15.32” N and 56°18'35.08”E with a total perimeter of 1,815 m and an area of 53,212 m^2. (Fig. 6).

With a pH >8.0 and EC just below 100mS/m, ATF's soils are sodic, highly dispersive, and have low to moderate levels of bioavailable nutrients. During a field survey, the two contour ditches were found (Fig. 7). Both have been eroded and broken by possible rainfall. The soil’s high dispersion indicates the causes of the blowout along the contour ditch. The high pH likely inhibits the uptake of key nutrients. Thus, despite high quantities of iron (double the iron available in the Al Taween site), potassium, phosphorous, manganese, and others in the soils, the bioavailability of these minerals is likely very low. The highest value of Iron is observed in ATF followed by Altaween and then Flag Park (Table 1 and Fig. 3). The fertilizers must be used to enhance the fertility of the soil on this site.

Temperature, precipitation, rainfall, and wind velocity data for 2021 and 2022 have been collected and analysed (Supplementary Material 2). During the months of April through September, the average temperature in ATF is between 45 and 50 degrees Celsius. From mid-March to June, the relative humidity decreases to 10 to 20%, while remaining above 60% for the majority of the year. The precipitation total for the month of January does not exceed 10 millimetres. Nevertheless, in August it exceeded 35mm. Less than 10mm of precipitation was recorded for the remainder of the year. In addition, during the first half of the year, the average wind speed in this region ranges between 18 and 40 kilometres per hour, with the exception of mid-January, when it consistently exceeds 58 kilometres per hour. In addition, later in the year, the wind speed was less than 25 kilometres per hour. According to calculations, 80 millimetres of annual precipitation can supply up to 34,400 cubic metres of water annually. We have also calculated the average monthly total precipitation (in millimetres) for the 18-year period from 2003 to 2021. (Supplementary Materials 3). The average precipitation for January, March, and December is 10, 15, and 17 millimetres, respectively.

The proposed afforestation recommendations are based on field trips and collected soil, temperature, wind speed, and average annual precipitation data. Two broken contour ditches demonstrated that further ditches are unnecessary. All drainage is captured by the dam below, thus repairing the ditches will not assist. Since Moringa peregrina appears to grow directly from rocky cliff faces, this tree could be recommended for propagation. There is a requirement for pumps and temporary irrigation. Numerous hectares of slope are suitable for reforestation using Moringa peregrina, and trials with additional native plants are recommended. Establishment requires drip irrigation, although it can be discontinued later. Planting seeds in January or February and applying drip irrigation for 120 days can be beneficial for the plantation. Mulch plantings to lower soil temperatures, encourage soil biota, and prevent evaporation. This improves the efficiency of drip irrigation greatly. Due to the strong wind velocity in this area, rock mulching is recommended over straw mulching. In arid regions, mulching can reduce soil temperatures by 30 degrees Celsius.

The Flag Park site (Fig. 8) is located within the coordinates 25°7'12.78”N and 56°17'7.87”E in the UAE, with a perimeter are 1,571 m, and the total area is 70,704 m².

According to the soil analysis, the values of iron, phosphorus, zinc, nickel, and manganese are higher in deep soil layers than in the top 10 cm layer of soil. Similarly, there is a higher amount of copper in the 50cm soil layer than the 10cm layer with a difference of around 8 mg/kg. The high conductivity and higher salinity are likely the result of irrigation. The 50 cm soil layer started to show lower salinity than the top layer. Manganese and phosphorus are observed to be elevated in all three visited locations. The analysis depicts that these soils are sodic and thus highly dispersive and erosive in rainfall and flash floods (Table 1).

Temperature, precipitation, rainfall, and wind speed values for 2021 and 2022 are listed in. (Supplementary Materials 4) The majority of the year has temperatures above 45 degrees. While the air is humid year-round, it is especially dry during the peak of the summer season, which is May and June. It rains an average of less than 10 millimetres every month aside from the month of August, when it can reach above 30 millimetres. Analysis suggests that windy conditions persist throughout the year. Given the average yearly precipitation of 137.4 millimetres, the total water output from rainfall can reach 10,000 cubic metres (Supplementary Materials 5).

Fig. (7). A break in the existing contour ditch in ATF site, created by the last rainfall.

Fig. (8). A view the FLAG PARK site with an approximate boundary determined by google.

Field surveys have revealed a number of eroding areas, most likely the result of a combination of erodible soil and excessive rainfall. An assessment suggests that terracing the hillside might be an expensive undertaking with long-term benefits for slope stabilisation, erosion prevention, and aesthetic enhancement of the park. Native tree species could potentially be planted there.