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The paper studied the impact of integrated plant nutrients management strategy (IPNM) on the agricultural return during current Syrian crisis through the application of camel manure and chemical fertilizers on the black cumin quantitatively and qualitatively. The fertilization treatments were denoted as T2 [N120-P30-K30], T3 [N120-P30-K60], T4 [5 t. ha-1camel manure], and T5 (1/2 [T3 + T4]), respectively. The no-fertilizer treatment (T1) was considered as control. Soil fertility, irrigation water use efficiency (IWUE), and oil content were considered. Results have showed that organic manure(camel dung)decreased soil pH and OC/ON ratio and increased the availability of nutrients in the soil. What led the black cumin to respond by significantly increasing the following productive parameters: plant height, roots depth, number of primary and secondary branches,..etc. The treatment T5 recorded the highest IWUE values (5.2 and 6.2 kg.ha-1.mm-1) and the best oil content (33.3% and 34.2%) in the two seasons, respectively. Furthermore, the applied IPNM strategy had remarkably increased fertilization efficiency and economical feasibility (profit/total costs) in the order of T5>T4>T3>T2 compared to T1. [ABSTRACT FROM AUTHOR]

In this paper, we examine the effect of vegetation on soil erosion, runoff generation and sediment transport on saline rangeland hillslopes. Rainfall simulations were conducted at a fixed 114 mm/h intensity on 6 m × 2 m erosion plots with varying degrees of vegetation. Plots were grouped into three categories (L, M and H) based on their canopy cover (L: <5%, M: 5–19%, H: >19%) and selected to limit variations in slope across canopy cover groups. Runoff and sediment samples were combined with three dimensional (3D) reconstruction data used to monitor soil surface microtopographic changes. Runoff initiation was significantly delayed on the L plots but cumulative runoff after 20 min of rainfall simulation indicated a positive effect of vegetation on infiltration processes. Cumulative sediment after 20 min of rainfall was similar across vegetation cover categories. The 3D data suggest that vegetation reduced net sediment delivery from the plots by primarily increasing opportunities for deposition while marginally affecting gross soil erosion. Plots with H vegetation cover experienced lower 3D-estimated erosion volumes but average erosion depth on L plots was lower than that on plots with M and H vegetation covers. Lower runoff volumes on M and H plots may have been compensated by greater runoff erosivity on these plots as runoff was concentrated in a narrower inter-patch space compared to L plots. This study highlights the need for an increased integration between traditional runoff measurement techniques and 3D reconstruction methods. [ABSTRACT FROM AUTHOR]

This research was conducted under the conditions of Syrian Baddia in Mehasseh center for scientific agricultural research at (Al Qaryatein), Three slops (8% , 6%, 4%) were applied in this study by using semi circular bunds with three Diameter ( 18, 12 ,6 ) m, in order to test the influence of the used water harvesting techniques in the ability of the soil in gathering rain water surface runoff efficiency compared with control which was executed by drawing the contour lines with same dimension of the bunds on the same three studied slops(8, 6, 4)%. The bunds and control were planted with Atriplex Halimus seedlings in the lower part of the archery. The following results were obtained: 1- watery storage in the soil increased by the increasing of the diameter of water harvesting bunds, and the highest value of the watery storage was (710.7) m3/ha behind the bunds with (18) m diameter, and the lowest value was (352.5) m3/ha behind the bunds with (6)m diameter. 2- The watery storage behind the all studied diameters of bunds (6, 12, and 18) m, increased by the increasing of the slope rate in the whole studied treatments compared with the control. 3-Using of water harvesting technique by bunds with different diameter (18m, 12m, 6m), raised the efficiency of the soil in gathering rain water after the runoff about ( 72.45 )% behind the bunds with diameter (18)m, (68.80%) behind the bunds with diameter (12)m, and (68.32%) behind the bunds with diameter (6)m, and always larger than efficiency of the soil at the control on the whole studied treatments. 4 - Using of water harvesting technique by bunds with different diameter (18m, 12m, 6m), increased the percentage success of the feeding plants about (70.56%) behind the bunds with diameter (18)m, (33.54%) behind the bunds with diameter (12)m, and (18.71%) behind the bunds with diameter (6)m compared with control, in addition to improve the vegetation cover by appearing some associated plants such as, Stepa Barbata, Poa bulbosa, Anabasis aphylla, and some annual plants 5- Using of water harvesting technique by bunds with different diameter (18m, 12m, 6m), increased the grazing capacity of the planted shrubs and associated plants about (93.3%) behind the bunds with diameter (18)m, (91.80%) behind the bunds with diameter (12)m, and (90.75%) behind the bunds with diameter (6) m compared with the control (without bunds). [ABSTRACT FROM AUTHOR]

Homs governorate watershed is considered as the agricultural production hub and a strategic water reservoir of Syria. However, land fertility and the increase of population, as well as climatic changes, urged the farmers in this region to intensify the agricultural development. This has resulted in increasing pressure on available water resources of upper Orontes River Basin. Therefore, it is necessary to develop a prediction model that helps to estimate future availability of water resources. This paper analyzes how some strategies can help the government in achieving sustainable development. Consequently, their water security in the wake of climate changes till 2050. Four scenarios were studied depending on the actual situation (RF) with improving the irrigation efficiency: (1) Reuse of reclaimed agricultural water return, (2) Optimum exploitation of Zeita reservoir, (3) The reducing of the per capita share of drinking water and minimizing evaporation from the surface of Kattenieh Lake, and (4) Separation between Homs-Hama networks and raising their water conveyance efficiency by exchanging them with pressured pipe networks. The aforementioned scenarios were through three cases of climate changes (normal, dry and very dry years). The results are visualized as graphs, maps and tables, and showed that by application of the first three scenarios, the critical point (water deficiency) will disappear with obtaining surplus about 38% comparing with (RF), to achieve water needs of Homs-Hama networks (third priority) in case of normal years and high irrigation efficiencies in 2050. Also, water deficiency will decrease about 93% and 65% in case of dry and very dry years, respectively. While by application of the fourth scenario with closed circuits of industrial plants, we can avoid water deficiency and reduction of pollution rate in case of dry years in 2050, and decrease its rate to 77% comparing with (RF) in case of very dry years. This will necessitate water withdrawal (about 200 MCM) from other nearby basin such as Coast basin to minimize the gap between supply and demand. [ABSTRACT FROM AUTHOR]

• Prescribed fire promoted herbaceous growth in bare interspaces. • Litter enhanced infiltration and provided protection against erosion. • Increased vegetation cover altered flow paths and reduced runoff and soil loss. • Reduced soil surface connectivity post-fire improved hydrologic function. • Hydrologic function continues to improve 9 yr after fire. Woody species encroachment into herbaceous and shrub-dominated vegetations is a concern in many rangeland ecosystems of the world. Arrival of woody species into affected rangelands leads to changes in the spatial structure of vegetation and alterations of biophysical processes. In the western USA, encroachment of pinyon (Pinus spp.) and juniper (Juniperus spp.) tree species into sagebrush steppes poses a threat to the proper ecohydrological functioning of these ecosystems. Prescribed fire has been proposed and used as one rangeland improvement practice to restore sagebrush steppe from pinyon-juniper encroachment. Short-term effects of burning on the ecohydrologic response of these systems have been well documented and often include a period of increased hydrologic and erosion vulnerability immediately after burning. Long-term ecohydrologic response of sagebrush steppe ecosystems to fire is poorly understood due to lack of cross-scale studies on treated sites. The aim of this study is to evaluate long-term vegetation, hydrologic, and erosion responses at two pinyon-juniper-encroached sagebrush sites 9 years after prescribed fire was applied as a restoration treatment. Thirty-six rainfall simulation experiments on 6 m × 2 m plots were conducted for 45 min under two conditions: a dry run (70 mm h−1; dry antecedent soils) and a wet run (111 mm h−1; wet antecedent soils). Runoff and erosion responses were compared between burned and unburned plots. Overall, increases in herbaceous cover in the shrub-interspace areas (intercanopy area between trees) at both sites 9 years post-burn resulted in runoff- and erosion-reduction benefits, especially under the wet runs. While the initially more degraded site characterized by 80% bare ground pre-burn, registered a higher overall increase (40% increase) in canopy cover, greater post-fire reductions in runoff and erosion were observed at the less degraded site (57% bare ground pre-burn). Runoff and erosion for the wet runs decreased respectively by 6.5-fold and 76-fold at the latter site on the burned plots relative to control plots, whereas these decreases were more muted at the more degraded site (2.5 and 3-fold respectively). Significant fragmentation of flow paths observed at the more-degraded site 9 years post-fire, suggests a decreased hydrologic connectivity as a mechanism of runoff and erosion reduction during post-fire recovery. [ABSTRACT FROM AUTHOR]

On sparsely vegetated arid and semi-arid rangelands, a feedback mechanism is thought to exist between vegetation patches and sediment transport processes. Relationships between plant cover and soil erosion and deposition have historically been inferred from the rates of detachment and transport of sediments presents in samples collected at the outlets of bounded observation areas. These point-scale traditional soil erosion assessment methods lack the spatial resolution needed to differentiate between the oft-described detachment-reducing and deposition-promoting effects of vegetation on net sediment yield. With the advent of low-cost three-dimensional (3D) reconstruction techniques such as Structure from Motion (SfM), it is possible to combine traditional erosion and runoff measurement techniques with 3D soil surface reconstructions to gain insight into the role of the amount and spatial distribution of vegetation in controlling sediment transport processes. In this study, we combine hydrology, soil loss and high-resolution SfM data from rainfall simulation experiments conducted on 84 plots across 7 sparsely vegetated sites of the western United States to understand how detachment and transport processes are impacted by the spatial distribution of vegetation. Previously developed surface change metrics were used to characterize erosion and transport processes from the SfM data and related to hydrology and biotic and abiotic land surface characteristics. This study sheds light into the dynamics of sediment transport on sparsely vegetated landscapes but also provide a framework for the integration of 3D surface change data to augment soil erosion assessment. [ABSTRACT FROM AUTHOR]