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Sand and dust storms (SDS) are a natural phenomenon dominantly originating in arid and semi-arid regions. The vastness and changing distribution of the SDS hotspots, their inaccessibility, and financial limitations are the greatest challenges to projects combating SDS. To boost project success, a prioritized site-selection method which incorporates the physical and human variables interacting with SDS is applied in this paper. This ensures that potential economic and health impacts of SDS on human populations are also included. Six variables were selected for analysis: within-region sand and dust hotspots, changing distribution of the hotspots, residential areas, vegetation cover, soil texture, and the maximum drought-inundation of the Hamoun wetland. SDS hotspot sites for possible stabilization were identified and prioritized using the multi criteria evaluation (MCE) method. Such prioritization assists the practical management of hotspots under conditions of resource and budgetary constraints which are especially common in developing countries. This paper thus provides a template for site selection and prioritization of SDS hotspots for remediation. It also highlights the importance of variables other than SDS source areas for selection of rehabilitation sites. The proposed method, using the Sistan region as an example, is applicable to other regions of the world as a means of reducing the negative effects of known dust storm hotspots. [ABSTRACT FROM AUTHOR]

The agricultural and environmental functionality of irrigation districts is sometimes controversial, with salinity as a frequent argument in the arid countries. In the 20th century, the Spanish Ministry of Agriculture studied the degree and extent of salinity and other facets of irrigated districts in Spain by conducting soil surveys and land evaluations from the 1940s to the early 1980s. This article presents a--probably partial--list and the available details of these studies for the Ebro Basin. We had access to some of these studies, although for most of them we only have indirect information; we also indicate the existence of these kinds of studies for other regions of mainland Spain. However, updated systematic estimations of the extent and degree of soil salinity are unavailable for most of the irrigated lands in Spain and for many other dry countries. A feasible task, as shown further in the article, is screening the value of the still readable studies and selecting the irrigation districts whose past documentation and present status allow for a new evaluation of soils, or at least measuring their actual salinity for comparison with the previous data. The results will help irrigators, government agencies, and other stakeholders in the appraisal of the effects of agricultural practices--chiefly the application of water--and to re-design them if needed. We advocate for the collection and critical review of the surviving soil studies, and for their rescue through scanning and digitalization. This task is compelling due to the decay of the existing paper documents. [ABSTRACT FROM AUTHOR]

In this paper we argue that historians of the eastern Arab lands (Ar. at-mashriq al-'arabi) should turn their attention to the Bedouins for two main reasons. First, the societies in the Arab East cannot be adequately understood without a full evaluation of their Bedouin component, especially outside urban areas. Second, studying the Bedouins can open new perspectives on important debates in Middle Eastern historiography. The paper further contends that the arid lands of the Arab East still need to be explored as a historical region with its own distinct patterns of regional connectivity and political organisation. Finally, we highlight environmental history and the study of emic categories as promising avenues for future research on this region. [ABSTRACT FROM AUTHOR]

Abstract: Ephemeral and intermittent streams are abundant in the arid and semiarid landscapes of the Western and Southwestern United States (U.S.). Connectivity of ephemeral and intermittent streams to the relatively few perennial reaches through runoff is a major driver of the ecohydrology of the region. These streams supply water, sediment, nutrients, and biota to downstream reaches and rivers. In addition, they provide runoff to recharge alluvial and regional groundwater aquifers that support baseflow in perennial mainstem stream reaches over extended periods when little or no precipitation occurs. Episodic runoff, as well as groundwater inflow to surface water in streams support limited naturally occurring riparian communities. This paper provides an overview and comprehensive examination of factors affecting the hydrologic, chemical, and ecological connectivity of ephemeral and intermittent streams on perennial or intermittent rivers in the arid and semiarid Southwestern U.S. Connectivity as influenced and moderated through the physical landscape, climate, and human impacts to downstream waters or rivers is presented first at the broader Southwestern scale, and secondly drawing on a specific and more detailed example of the San Pedro Basin due to its history of extensive observations and research in the basin. A wide array of evidence clearly illustrates hydrologic, chemical, and ecological connectivity of ephemeral and intermittent streams throughout stream networks. [ABSTRACT FROM AUTHOR]

Lake Urmia, in northwest Iran, is the second most saline lake in the world. During the past two decades, the level of water has markedly decreased. In this paper, climate of the lake region is investigated by using data from four meteorological stations near the lake. The data include climatic parameters such as temperature, precipitation, humidity, wind speed, sunshine hours, number of rain days, and evaporation. Climate around the lake is examined by way of climate classification in the periods before and after the reduction in water level. Rainfall in the lake catchment is also evaluated using both gauge and satellite data. The results show a significant decreasing trend in mean annual precipitation and wind speed and an increasing trend in annual average temperature and sunshine hours at the four stations. Precipitation and wind speed have decreased by 37 mm and 2.7 m/s, respectively, and the mean annual temperature and sunshine hours have increased by 1.4 °C and 41.6 days, respectively, over these six decades. Only the climate of the Tabriz region is seen to have significantly changed, going from semiarid to arid. Gauge records and satellite data show a large-scale decreasing trend in rainfall since 1995. The correlation between rainfall and year-to-year changes in lake level is 0.69 over the period 1965 to 2010. The relationship is particularly strong from the early 1990s to 2005. This suggests that precipitation has played an important role in the documented decline of the lake. [ABSTRACT FROM AUTHOR]

Abstract: The delta of the Colorado River in Mexico supports about a million hectares of riparian, marsh and estuarine habitats of international importance. Some of these habitats depend on flows of fresh and brackish water from the U.S. and Mexico. Up to now, these flows were the incidental result of water management actions taken to provide water for agriculture and municipal use, protect against flooding, and dispose of saline agricultural return flows. This paper briefly describes the wetlands and documents recent bi-national efforts to provide environmental flows to the delta, codified in Minutes 306, 316 and 319 of the water treaty between the U.S. and Mexico for the utilization of Colorado River water. Providing water for environmental uses in this watershed will be a daunting task given the many competing uses for water and expected diminished flows due to climate change. The paper serves as an introduction to a special issue of Ecological Engineering, Wetlands of the Colorado River Delta, which contributes 17 new research articles to the science based on these diverse aquatic habitats. We hope these studies will be useful to those developing management strategies to preserve and enhance these habitats for the future. [Copyright &y& Elsevier]

Beginning in the early twentieth century and progressing rapidly since the 1950s, large-scale water works have created engineered rivers. In dry-land basins they control flooding and provide water and energy to farms, cities and industry. Yet, they face numerous challenges. In 2013 we formed an interdisciplinary team to study future conditions of nine river basins worldwide. This paper presents the methodology and interim results for two of our basins, the Rio Grande and the Euphrates-Tigris. We conclude with a new definition of the sustainability of engineered rivers in arid lands, using dependable reservoir yield under drought conditions as the central indicator. [ABSTRACT FROM PUBLISHER]

In a companion paper, the agricultural drought economic risk assessment (ADERA) model was described. ADERA studies agricultural drought not only in terms of deficit soil water content and its frequency and severity (as in the traditional approach) but also in terms of net benefit reduction and vulnerability. The relationship between drought index, crop yield, and crop economic net benefit is modeled and three threshold levels are considered: the critical water content; the critical impact in terms of net benefit; and its critical return period (i.e., frequency) above which the soil-climate unit is considered unsuitable for the cultivation of a specific crop. These critical levels are used in long-term action planning as the triggers for different risk classes. The rapidity with which the critical impact is reached is considered indicative of the crop vulnerability, and real-time monitoring of the impact evolution (short-term actions) is also implemented. Initially ADERA was applied at only one point (soil-crop-climate unit), but because agricultural drought is by definition a wide area phenomenon, the model must be validated in other units and then used to evaluate the drought area extension (risk map). In this paper, generalization, demonstration, and guidance on the application of ADERA are given with reference to rainfed sunflower and sorghum crops in six soil-climate units in central Italy for which time series for yield (obtained in experimental plots where the water scarcity was the principal factor limiting the final yield) since 1978 is available. The application of ADERA made it possible to quantify the vulnerability class and the corresponding risk class for the single unit (long-term action planning). The analysis results confirm that typically for the selected crops the critical impact has a low risk and a low vulnerability. In fact sunflower and sorghum are rainfed crops widely cultivated in the area under investigation. Moreover, the results show that each risk class is present only within a specific cost range, in particular the upper and lower limits, and the size of each cost range varies according to the different units; the occurrence of a specific risk class and vulnerability level is highly correlated with the selected triggers, in particular with the critical net benefit (for an increment of which above the corresponding cost range, a given soil-climate unit can become unsuitable for the cultivation of a specific crop); the critical water content is a normal occurrence event for all the units analyzed, with the crop water stress onset date always around 40% of the growing period being a typical characteristic of the specific area, of the two crops and of the selected drought index. The practical usefulness of the impact monitoring procedure was stressed by comparing its progressive evolution in the cases of both a rainfed crop and of a rescue irrigation carried out at a selected and opportune date. In the latter case the impact was reduced below the critical level. [ABSTRACT FROM AUTHOR]

With their modest rainfall, arid regions are characterized by relatively fewer species than the better-watered biomes. But this makes it all the more important that the biodiversity that is present in arid environments be given even higher priority; for each species lost from an arid region, the percentage of loss for the region''s biodiversity is much higher than in more species-rich regions. And some species, such as bees and ants, are particularly diverse in arid habitats. Realizing the importance of biodiversity in the arid regions where they live, local people have devised numerous ways of limiting their impact. Historically, such regions have been especially subject to changes in climate, which affect productivity; these changes have often been accompanied by conflicts. The paper will describe these from various parts of the arid world, as a basis for comparison. The paper will also examine economic issues relating to biodiversity in arid lands, focusing especially on the relationship between biodiversity and various kinds of development projects. The major challenges in implementing the Convention on Biological Diversity (CBD) in arid lands lie not so much in the biology of the species concerned, but rather in the social, economic, and political arenas within which people operate. We need to build a broader constituency for conserving biodiversity, extend the responsibility for conserving biodiversity far beyond government, bring local people into the conservation movement, ensure that sufficient information is available to those who need it, restore degraded ecosystems, and stimulate far greater public support for biodiversity. [Copyright &y& Elsevier]

Assemblage patterns could be primarily generated by two types of drivers: exogenous (such as environmental and climatic factors) and endogenous (interactions such as competition, predation, mutualism or herbivory). The most widely accepted hypothesis states that at smaller scales (such as patch scale), interspecific interactions are the major drivers structuring communities, whereas at larger regional scales, factors such as climate, topography and soil act as ecological filters that determine assemblage composition. The general aim of this paper is to compare different exogenous drivers in terms of their relative dominance in structuring desert small mammal communities across a range of spatial scales, from patch to regional, and compare them with previous results on endogenous drivers. Our results show that as spatial scale increases, the explanatory power of exogenous factors also increases, e.g. from 17% at the patch scale (i.e. abundance) to 99% at the regional scale (i.e. diversity). Moreover, environmental drivers vary in type and strength depending on the community estimator across several spatial scales. On the other hand, endogenous drivers such as interspecific interactions are more important at the patch scale, diminishing in importance towards the regional scale. Therefore, the relative importance of exogenous versus endogenous drivers affects small mammal assemblage structure at different spatial scales. Our results fill up a knowledge gap concerning ecological drivers of assemblage structure at intermediate spatial scales for Monte desert small mammals, and highlight the importance of dealing with multi-causal factors in explaining ecological patterns of assemblages. [ABSTRACT FROM AUTHOR]

Mesquite is one of the most important forest resources in northern Mexico, constituting an important part of the national flora and its great importance to the inhabitants of the arid and semiarid regions. This paper shows a volumen and wood weight table obtained in m³ which can be used in the área of influence. This technique was based on dimensional analysis, measuring the tres readily available, which enables farmers, foresters and institutions, rely on production parametersand volumen of timber (wood) for the rational and sustainable use of natural populations of mesquite, in turn providing protection and conservation of the environment. The evaluation was conducted in Ejido San Antonio de la Sierrecilla, municipality of Mazapil, Zacatecas. The largest diameter was measured on crown and total height in cm, destructive sampling was carried out in 39 trees, and volume and weight of branches were determined. In regression analysis polynomial model was used resulting in timber volumen (m³)=2,341E-6X²-0,0012X+0,1803 and determination of weight (kg)=0,001X2- 0,556X+81,909*D with 95% reliability. [ABSTRACT FROM AUTHOR]

Monitoring soil salinization has been a difficult process in arid lands due their large spatial and temporal variability. Hyperspectral remote sensing has offered a potential for faster detection of salinization process but mostly from empirical approaches. In this paper, an integrated approach combining model inversion and empirical regressions has been proposed for soil salt content (SSC) estimation from hyperspectral information obtained from controlled laboratory experiments. All soil samples were artificially salinized using \Na2\SO4, NaCl, and \Na2 \CO3 (99% purity) salts to different levels and to different soil-moisture conditions, since soil moisture often jointly affects reflectance spectra with SSC. Hapke model was calibrated and validated for its simulation on soil reflectance and showed good agreements with measured data. The optimal values of single scattering albedo that was inversely retrieved from the Hapke model had good relationships with SSC at 2000–2200 nm for each treatment even under various soil-moisture conditions. Taking usage of these findings, the integrated approach obtained high accuracies on SSC estimations with R^2's of 0.90, 0.86, and 0.72 and slightly dropped R^2's of 0.89, 0.81, and 0.67 for NaCl-, \Na2\SO4-, and \Na2\CO3-type saline soils under respective dry and wet conditions. The R^2 decreased to 0.55 and 0.53 for dry and wet soils when salt types were ignored. The integrated approach provides a novel as well as an efficient way for SSC estimation from reflected spectra, and hence, we foresee its potential applications for large-scale SSC mapping from reflectance measurements. [ABSTRACT FROM PUBLISHER]

Climate change impact reports by the Intergovernmental Panel on Climate Change (IPCC) are well established throughout the world. By now many local, regional, and central authorities are aware of these impacts and they try to take necessary precautions according to their environmental circumstances. Preliminary decisions cannot be taken unless there is a model for future climate change impacts, especially for rainfall occurrence, amount, and frequency estimations. The main purpose is to combine the general circulation (climate) model (GCM) outputs with the local meteorology station records by a suitable downscaling procedure. In this paper, a statistical quadrangle downscaling model (QDM) is developed for rainfall estimations up to 2100. This model helps to downscale the nearby four scenario rainfall amounts at GCM grids to a desired point. Two main steps in the model structure are the use of a regional dependence function (RDF) for transferring the GCM output data from the four nearest grid points to the location. The second step is to adjust the downscaled scenario monthly rainfalls with the local rainfall records. The GCM monthly rainfall outputs are downloaded from the National Center for Atmospheric Research (NCAR) with special report emission scenario A2. The application of the methodology is presented for Riyadh City, Kingdom of Saudi Arabia (KSA). The RDF is obtained from the most reliable meteorology records at 27 locations that are irregularly scattered all over the country. Then it is used for scenario data transfer from the regular grid points. The adjustment is based on the average statistical properties of concurrent monthly rainfall amounts between 1985 and 1996. The trend component in the GCM remains intact. It has been observed that there is a major increasing trend in the monthly rainfalls after 2050. In the meantime, each decade starting from 2011 gives estimates that indicate steady rainfall increases up to 2050. The QDM indicates a 40% increase in the annual total rainfall amounts, with a 15% standard deviation increase. [ABSTRACT FROM AUTHOR]

The Limarí River basin is one of the most important watersheds in north-central Chile (30°S). Its headwaters lie at the top of the subtropical Andes ( above sea level) and the river flows westward into the Pacific Ocean over a length of approximately 200 km. This basin has a marked snowmelt-driven hydrological regime and, in spite of the arid conditions that characterize this region, holds more than 50,000 ha of highly productive agricultural land thanks to its irrigation infrastructure and three interconnected reservoirs. Like many semiarid regions around the world, north-central Chile is expected to become warmer and drier during the 21st century as a consequence of ongoing anthropogenic climate change. The associated reduction in streamflow, changes in hydrograph timing, and enhanced evapotranspiration will undoubtedly threaten agriculture in the Limarí basin and elsewhere in semiarid Chile. In this paper, the effect of temperature and precipitation on surface hydrology, performance of water infrastructure, and irrigation coverage in the Limarí basin is investigated by using the water evaluation and planning (WEAP) model. WEAP was calibrated by using current climate and agriculture patterns, and then forced with a set of 30-year-long climate scenarios, each of them obtained by adding a temperature and precipitation perturbation to the historical time series. This delta approach allows (1) determination of the sensitivity of selected variables to climate change, and (2) obtaining a projection of the effects in irrigation coverage expected for the near and far future (2010-2040 and 2070-2100, respectively). Both aspects are investigated for agricultural districts with varying access to irrigation infrastructure and groundwater; this exercise highlights the relevance of added storage and innovative conjunctive use of surface and groundwater resources for improving the resilience and adaptability of irrigated agriculture in the face of a changing climate. [ABSTRACT FROM AUTHOR]

Net radiation (Rn) is the main driving force of evapotranspiration (ET) and is a key input variable to the Penman-type combination and energy balance equations. However, Rn is not commonly measured. This paper analyzes the impact of 19 net radiation models that differ in model structure and intricacy on estimated grass and alfalfa-reference ET (ETo and ETr, respectively) and investigates how climate, season and cloud cover influence the impact of the Rn models on ETo and ETr. Datasets from two locations (Clay Center, Nebraska, subhumid; and Davis, California, a Mediterranean-type semiarid climate) were used. Rn values computed from the 19 models were used in the standardized ASCE-EWRI Penman-Monteith equation to estimate ETo and ETr on a daily time step. The influence of seasons on the estimation of Rn and on estimated ETo and ETr was investigated in winter (November-March) and summer (May-September) months. To analyze the influence of clouds on the impact of Rn models, relative shortwave radiation (Rrs) was used as a means to express the cloudiness of the days as: 0≤Rrs≤0.35 for completely cloudy days; 0.35

The paper proposes a new methodology that studies agricultural drought not only in terms of deficit soil water content, its frequency and severity, as in the traditional approach, but also in terms of net benefit. For this purpose the relationship between drought index, crop yield, and crop economic net benefit is modeled and three threshold levels are considered. The first is the critical water content, below which the crop faces water stress (termed as potential agricultural drought). The second is the critical net benefit, below which there is meager (e.g., zero) profit (termed as actual agricultural drought). The third is the critical return period (or frequency) of the actual agricultural drought, below which there is an agricultural aridity (almost steady phenomenon with high impact, high risk) and above which there is an agricultural drought (occasional phenomenon with high impact, low risk). To pinpoint the time of occurrence of the potential and the actual agricultural drought, real-time monitoring is conducted. The rapidity with which these critical conditions are reached is considered as indicative of the crop vulnerability to the corresponding phenomenon. The evolved methodology therefore is based on an objective definition of agricultural drought and is formulated accounting for its peculiar characteristics. The methodology is called the risk analysis and economic impact assessment of agricultural drought (ADERA). ADERA is applied to the rainfed sunflower crop in the Papiano (central Italy) experimental plots for which the 26-year time series for yield and the corresponding phenological, climatic, and economic data are available. The drought index-crop yield-crop economic net benefit relationship makes it possible to quantify the frequency (return period) of the actual agricultural drought and to show that for the given costs and crop sale price the actual agricultural drought risk for the crop is low. For the case study, the vulnerability of the unit to the agricultural drought is low, as the critical net benefit typically occurs late in the growing season. [ABSTRACT FROM AUTHOR]

In this paper, unconfined porous medium is considered to drain vertically to an underlying fractured aquifer, which leads groundwater to a variable large diameter well blind to porous medium. Such cases are quite common in arid regions, where the geological layers have top to bottom sequence as quaternary sedimentary layer (porous-unconfined aquifer), weathered and/or fractured underlying layers (fractured-confined aquifer), which are underlain by impervious rock formation. The necessary type curves are provided both for the fractured (pumped) and overlying porous (unpumped) media. Initially, the effect of varying well diameter on the drawdown is explained. The general groundwater movement equation for this configuration yields to well known Theis, Hantush, and Jacob solutions. It is also indicated that at large times, classical Jacob straight line is not valid in every case, because there is a set of other straight lines with different slopes. The application of the methodology is presented for an aquifer test in the Kingdom of Saudi Arabia. [ABSTRACT FROM AUTHOR]

Abstract: Floodplains in arid lands can be agriculturally productive, but they can also be geomorphically unstable environments. Many of the floodplains of higher order basins in southern portion of the Basin and Range Province of the American Southwest have been farmed intermittently for hundreds of years, and continuously for the past century. In order to be productive, however, these floodplains were modified considerably by human agency. This paper reviews the different types of human manipulations to floodplains that may result in land degradation and geomorphic change, including vegetation, topography, soils, hydrology, and channel banks. Emphasis is on the direct and indirect consequences of geomorphic modification, and the long-term viability of such changes in the contexts of landscape sensitivity and sustainability. Evidence documents transformation of natural floodplains to agricultural surfaces, with examples from southern Arizona, USA, and Sonora, México. [Copyright &y& Elsevier]

Abstract: This paper explores environmental hazards, more specifically desertification processes, in an area of west central Argentina, addressing the combined influence of the physical framework and the long lasting human settlement and use of natural resources. It is based upon the analysis of remotely sensed using vegetation indices, image differentiation, change detection, and pattern metrics. The results indicate a net decreased in the amount of vegetation between 1973 and 2001, and increasing fragmentation of vegetation classes. This is interpreted as a sign of the presence of land degradation processes likely linked to human activities in the areas of irrigated farming, grazing, firewood gathering and population settlement. [Copyright &y& Elsevier]

This paper presents the area and water allocation model (AWAM), which incorporates deficit irrigation for optimizing the use of water for irrigation. This model was developed for surface irrigation schemes in semiarid regions under rotational water supply. It allocates the land area and water optimally to the different crops grown in different types of soils up to the tertiary level or allocation unit. The model has four phases. In the first phase, all the possible irrigation strategies are generated for each crop-soil-region combination. The second phase prepares the irrigation program for each strategy, taking into account the response of the crop to the water deficit. The third phase selects the optimal and efficient irrigation programs. In the fourth phase of the model, irrigation programs are modified by incorporating the conveyance and the distribution efficiencies. These irrigation programs are then used for allocating the land and water resources and preparing the water release schedule for the canal network. [ABSTRACT FROM AUTHOR]

In this work, applications of the coupled solid set sprinkler irrigation and crop model AdorSim introduced in the companion paper are presented. The sprinkler irrigation model is based on ballistic theory, while the crop model is based on CropWat. AdorSim was used to evaluate the effect of sprinkler spacing on seasonal irrigation water use (WU) and crop yield. The most relevant results were related to the characterization of advanced irrigation scheduling strategies. The differences in crop yield and WU derived from irrigating at different times of the day were estimated for two locations strongly differing in wind speed. Irrigation guidelines were established in these locations to relate gross water use and water stress induced yield reductions. Simulations were also applied to estimate adequate wind speed thresholds for irrigation operation. In the experimental conditions, thresholds of 2.0–2.5 m s-1 proved effective to control yield reductions and to minimize WU. [ABSTRACT FROM AUTHOR]

This paper examines the mid- to late-Holocene (c. 6850-1160 cal. yr BP) environmental history of Sierra de Gádor in southern Spain. The local vegetation dynamics are reconstructed through the palaeoecological record obtained from a lacustrine deposit situated at 1530 m. Various hypotheses are considered to explain the vegetation dynamics apparent in the palaeoecological evidence, including climatic change, fire occurrence and human activity. Although the vegetation in this region is sensitive to climatic change, threshold events driven by ecological factors are also apparent. Climatic events include a thermo-mesophytic optimum with abundance of deciduous trees and maximum lake water level found from c. 6850 to 5500 cal. yr BP. In contrast, changes in the frequency of major fire episodes appear to have shaped interspecific relationships and vegetation change, especially from c. 4200 cal. yr BP onwards. Biotic properties of the ecosystem such as the inertia of established tree populations, interconnected with competition adjustments, appear also to have played a role. Over the last two millennia, overgrazing, combined with natural and/or human-set fires, appears to have pushed mountain forests over a threshold leading to the spread of grassland, thorny scrub, junipers and nitrophilous communities. [ABSTRACT FROM AUTHOR]

The study was conducted to evaluate the potential of different strains of plant growth-promoting rhizobacteria (PGPR) to reduce the effects of salinity stress on the medicinal hopbush plant. The bacterium factor was applied at five levels (non-inoculated, inoculated by Pseudomonas putida, Azospirillum lipoferum + Pseudomonas putida, Azotobacter chroococcum + Pseudomonas putida, and Azospirillum lipoferum + Azotobacter chroococcum + Pseudomonas putida), and the salinity stress at six levels: 0, 5, 10, 15, 20, and 50 dS m-1. The results revealed that Pseudomonas putida showed maximal germination percentage and rate at 20 dS m-1 (18.33% and 0.35 seed per day, respectively). The strongest effect among the treatments was obtained with the treatment combining the given 3 bacteria at 15 dS m-1 salinity stress. This treatment increased the root fresh and dry weights by 31% and 87.5%, respectively (compared to the control). Our results indicate that these bacteria applied on hopbush affected positively both its germination and root growth. The plant compatibility with the three bacteria was found good, and the treatments combining Pseudomonas putida with the other one or two bacteria discussed in this study can be applied in nurseries in order to restore and extend the area of hopbush forests and akin dry stands. [ABSTRACT FROM AUTHOR]