Semi-arid Zone Research Articles

Cultivated and wild pearl millet display contrasting patterns of abundance and co-occurrence in their root mycobiome

Fungal communities associated with roots play a key role in nutrient uptake and in mitigating the abiotic and biotic stress of their host. In this study, we characterized the roots mycobiome of wild and cultivated pearl millet [Pennisetum glaucum (L.) R. Br., synonym: Cenchrus americanus (L.) Morrone] in three agro-ecological areas of Senegal following a rainfall gradient. We hypothesized that wild pearl millet could serve as a reservoir of endophytes for cultivated pearl millet. We therefore analyzed the soil factors influencing fungal community structure and whether cultivated and wild millet shared the same fungal communities. The fungal communities associated with pearl millet were significantly structured according to sites and plant type (wild vs cultivated). Besides, soil pH and phosphorus were the main factors influencing the fungal community structure. We observed a higher fungal diversity in cultivated compared to wild pearl millet. Interestingly, we detected higher relative abundance of putative pathotrophs, especially plant pathogen, in cultivated than in wild millet in semi-arid and semi-humid zones, and higher relative abundance of saprotrophs in wild millet in arid and semi-humid zones. A network analysis based on taxa co-occurrence patterns in the core mycobiome revealed that cultivated millet and wild relatives had dissimilar groups of hub taxa. The identification of the core mycobiome and hub taxa of cultivated and wild pearl millet could be an important step in developing microbiome engineering approaches for more sustainable management practices in pearl millet agroecosystems.

Agro-Fruit-Forest Systems Based on Argan Tree in Morocco: A Review of Recent Results.

The argan tree, Argania spinosa (L.) Skeels, is a horticultural forestry species characterized by its endemicity and adaptation to arid and semi-arid zones in the southwest of Morocco. Despite its limited geographical distribution, argan tree presents large genetic diversity, suggesting that improvement of argan is possible. This species plays important ecological, and socioeconomic roles in the sustainable development of the country. The integration of arganiculture into Moroccan agricultural policy has been implemented through a sector strategy, which is fully aligned with the conservation and regeneration of argan forest. A. spinosa is suitable for incorporation into different agroforestry productive systems under agro-fruit-forest model and its domestication will provide a powerful means of socio-economic and environmental management. Here, we provide an overview of the argan tree literature and highlight the specific aspects of argan stands, as agro-forest systems, with the aim of developing an adequate strategy of conservation and domestication of this species. We introduce promising programs and projects for argan plantations and arganiculture, which have been adopted to relieve anthropogenic pressure on the natural argan forest.

Act of phosphorus on cell hydraulic state, K+ use efficiency and induction of positive correlations between yield and vegetative traits in chickpea

ABSTRACT Salinity is one of the most severe factors that can affect agricultural productivity worldwide particularly in the arid and semi-arid agro-ecological zones. Chickpea seedlings were grown in the field and subjected to different NaCl concentrations (0, 50 and 150 mM) and P application (90 kg ha–1). The experimental design was based on a completely randomised design with three replications. Salinity has disturbed the physiological and ionic state of cells by increasing stomatal resistance and significantly decreased growth and yield parameters (−66%). Under salinity, plant growth traits presented a negative correlation with yield components. P application had positive effect on growth parameters and physiological responses of the plants. Our results suggest that the tolerance of chickpea at (NaCl × P) combination is closely associated with ionic homeostasis and physiological activities of the plants. Phosphorus application allowed salinity tolerance by increasing leaf hydraulic statute, improvement of KUE and consequently enhanced grain yield of chickpea. (P × salinity) combination induced a positive correlation between vegetative traits and yield parameters like unstressed treatment. These results suggest that the use of suitable amounts of phosphorus fertiliser (i. e. 90 kg ha–1) to saline soil is a beneficial starter for plant development, yield components and rehabilitation of degraded soils.

Monitoring and Modeling of Saline-Sodic Vertisol Reclamation by Echinochloa stagnina

Soil salinity due to irrigation is a major constraint to agriculture, particularly in arid and semi-arid zones, due to water scarcity and high evaporation rates. Reducing salinity is a fundamental objective for protecting the soil and supporting agricultural production. The present study aimed to empirically measure and simulate with a model, the reduction in soil salinity in a Vertisol by the cultivation and irrigation of Echinochloa stagnina. Laboratory soil column experiments were conducted to test three treatments: (i) ponded bare soil without crops, (ii) ponded soil cultivated with E. stagnina in two successive cropping seasons and (iii) ponded soil permanently cultivated with E. stagnina with a staggered harvest. After 11 months of E. stagnina growth, the electrical conductivity of soil saturated paste (ECe) decreased by 79–88% in the topsoil layer (0–8 cm) in both soils cultivated with E. stagnina and in bare soil. In contrast, in the deepest soil layer (18–25 cm), the ECe decreased more in soil cultivated with E. stagnina (41–83%) than in bare soil (32–58%). Salt stocks, which were initially similar in the columns, decreased more in soil cultivated with E. stagnina (65–87%) than in bare soil (34–45%). The simulation model Hydrus-1D was used to predict the general trends in soil salinity and compare them to measurements. Both the measurements and model predictions highlighted the contrast between the two cropping seasons: soil salinity decreased slowly during the first cropping season and rapidly during the second cropping season following the intercropping season. Our results also suggested that planting E. stagnina was a promising option for controlling the salinity of saline-sodic Vertisols.

Socio-Environmental Determinants and Human Health Exposures in Arid and Semi-Arid Zones of Iran-Narrative Review.

Lifestyle is different in arid and semi-arid zones. However, where people are born and live have a lasting influence on their social and environmental exposure. This review focuses on the, various dimensions of environmental health imbalance inequality especially in significant environmental sources such as (ie, air, water, soil) among provinces that creates a big health gap in the center, East and the Southeast of Iran. Thus, the population of the arid and semi-arid zones of Iran is facing respiratory, cardiovascular, cancer and infection diseases linked to environmental problems such as chemical and microbial pollution due to air pollution and unsafe water sources, respectively. The prevalence of certain types of cancer such as skin, stomach, bladder, prostate and colorectal cancer together with some respiratory and cardiovascular diseases in arid and semiarid zones such as Kerman, Yazd, etc., has been reported in comparison with other provinces frequently. These impacts have effects on multiple levels of health security in those zones. Based on these concerns, we propose key questions that should guide research in the context of the socio environmental science to support science-based management actions in Iran and other similar semi-arid areas worldwide.

Statistical Analysis of Groundwater sample of Sirohi village of Neemkathana block of Sikar (Rajasthan) India

In this study, the statistical analysis of groundwater of Sirohi village of Neemkathana block, Sikar (India) has been presented. Groundwater samples were taken from the se-lected sites strictly as per BIS norms. The TDS level of Sirohi village was found to be more than the acceptable limit of 500 mg/L. The higher TDS will affect human health. Neemkathana block in Rajasthan is a semi-arid zone, due to a continuous decrease in the value of rainfall, the rate of recharge of the water aquifer is imbalanced by yield. The average discharge from wells in alluvium ranges from 40m3/day to 90m3/day. Such kind of situation makes contamination to be at the extreme.

Influence of Age, Parity, and Fetuses’ Number on Blood Parameters in RembiEwes during Late Pregnancy in Semi-Arid zone, Algeria

Several nutritional problems can be observed in ewes with advanced pregnancy when energy demands related to fetal development increase, then can hurt ewes and their lambs during this period. The aim of our study was the assessment of hematological and some biochemical parameters changes in ewes during late pregnancy and the influence of age, parity, and fetuses number on the latter. In this study blood samples were collected from forty ewes of the Rembi breed during the end of pregnancy, housed

HPLC-DAD phenolic screening and in vitro assessment of antimicrobial, antioxidant and anti-inflammatory activities of Tanteboucht dates.

The date palm (Phoenix dactylifera L.) is one of the most important crops in arid and semi-arid zones. Date fruit occupies a good place in traditional medicine among the Saharan residents, due to its therapeutic virtues; although there may be several therapeutic virtues yet to be discovered. The aim of this study was to investigate the phytochemical and pharmacological properties of the hexanic (EHx), chloroformic (ECh), ethyl acetate (EAc) and aqueous (EAq) extracts of Tanteboucht pulp. The phytochemical characterization and estimation of phenolic compounds were done based on an HPLC-DAD approach. The antioxidant activity was evaluated by a DPPH scavenging effect test. The sensitivity of 7 bacterial strains and Candida albicans to Tanteboucht extracts was tested using the diffusion disc on agar medium method. The membrane stabilization test was used to determine the in vitro anti-inflammatory effect of the fruit extracts. Fourteen phenolic compounds were detected in organic extracts and EAc was the richest followed by ECh and finally EHx which was very poor in these molecules. All extracts showed antioxidant, anti-inflammatory and antimicrobial properties which differ in rate. Indeed, ECh had the greatest scavenging effect on DPPH, followed by EAc and then EAq. EAc was the most potent inhibitor of microbial strains. EAc and ECh were more efficient at membrane stabilization followed by EAq and the three extracts had more anti-inflammatory capacity than the positive control acetyl salicylic acid. The obtained considerable activities were significantly correlated with flavonoid and tannin contents in the extracts.

Habitat selection and food choice of White-naped Cranes (Grus vipio) at stopover sites based on satellite tracking and stable isotope analysis

By combining satellite tracking, land-cover extracted from Landsite 8 images, and the traditional stable isotope analysis, we studied the habitat selection and food preference of a vulnerable migratory waterbird, the White-naped Crane (Grus vipio), in one of its key stagging sites, the Shandian River Basin in the semi-arid northern China, to provide knowledge that is critical for its conservation in the Anthropocene. Our results showed that the White-naped Cranes used both uplands and natural wetlands in the stopover site. While the cranes used farmland and natural land cover equally as night-time roosting grounds, they spent most daytime foraging at farmlands. Despite the extensive usage of croplands as their foraging ground, the Bayesian mixing models based on stable isotopic analysis revealed that crop residues after harvesting, such as Maize (Zea mays) and Naked Oat (Avena chinensis), were only a small fraction of the White-naped Cranes’ diet (∼19%), and their diet composited mainly natural plants, such as Allium ledebourianum, Potentilla anserina, and P. tanacetifoli. Moreover, more than 20% of the total wetlands in the region were modelled as home range of the cranes. On contrast, less than 10% of croplands and about 1% of the unused uplands were identified as home range. In addition, the entire core habitats were located in natural wetlands. Our findings demonstrated the importance of natural wetlands for the survival of the threatened crane. However, the satellite-derived land cover data showed that croplands increased rapidly in the last decade in this area, at the expense of natural wetlands. With the sharp decrease of White-naped Crane population in China, the conservation of stopover sites becomes imperative. Based on our analysis, we recommend the following management actions: conserving adequate natural wetland area, regulating anthropogenic pressures such as the use of herbicides, expanding the duration and extent of current conservation regulations, establishing a comprehensive monitoring program, and initiating basin-scale ecological restoration, for effective conservation of this threatened species. These integrated conservation strategies for migratory waterbirds are necessary, considering the rapid land-cover changes and agricultural expansion that have been occurring in East Asian-Australasian Flyway, especially in the semi-arid temperate zone.

库布齐沙漠南缘风沙-植被相互作用及其景观效应

PDF HTML阅读 XML下载 导出引用 引用提醒 库布齐沙漠南缘风沙-植被相互作用及其景观效应 DOI: 10.5846/stxb202101270289 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（41671002）；青海省重点研发与转化计划项目（2019-HZ-814-1） Interaction between aeolian processes and vegetation and its landscape effect in the southern fringe of Hobq Desert Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:干旱区尤其沙漠边缘地区的风沙与植被相互作用对塑造地表景观具有重要意义。选择库布齐沙漠南缘的油蒿灌丛地为研究区，开展了植被调查、风沙流观测和表层沉积物粒度采样测试，分析了顺风向植被盖度、风沙流结构与沉积物特征的沿程变化，探讨了风沙-植被相互作用及其对地表景观格局的影响。结果表明，风沙流与植被相互作用方式的改变使植物生长状况与地表蚀积模式发生变化，进而导致顺风向景观表现出明显的空间异质性。自上风向裸地过渡到均匀分布的新生油蒿和油蒿灌丛再至斑块状分布的灌丛沙堆，植被盖度与覆沙厚度先增大后减小，空气动力学粗糙度沿程不断增加且在过渡时其增幅最大，输沙率与沉积物粒度呈先减小后增大趋势，并在植被盖度与覆沙厚度最大处出现最小值。在沙漠边缘剥蚀高原上，起初适量风沙堆积促进油蒿定植与生长，均匀分布的油蒿灌丛进一步促进沙物质堆积，但当堆积厚度超过油蒿耐沙埋深度时发生退化，灌丛出现斑块状分布且风沙流在丘间地处侵蚀。据此，可理解为剥蚀高原风沙区景观异质性是风沙与植被相互协同与抑制作用的结果。 Abstract:The interaction between aeolian sand drift and vegetation in arid region, especially in the fringe of desert, is of great significance in shaping the surface landscape. To be specific, in the process of aeolian sediment transport, the fine particles provide nutrients and water for vegetation colonization and growth, and when plants grow to a certain extent, they affect the pattern of sand erosion and accumulation by covering surface, capturing sand materials and dispersing wind energy. The change of the pattern and the difference of vegetation growth make the landscape appear spatial heterogeneity. In order to explore the interaction between aeolian processes and vegetation and the resulting landscape heterogeneity, the Artemisia ordosica shrub land in the southern fringe of Hobq Desert, which was located in the arid and semi-arid transition zone, was selected as the study area, and then vegetation investigation, the field observation of air flow, sand transport rate and sampling of sediment grain size were carried out. Based on the work, we analyzed the changes of vegetation coverage, air flow structure and sediment grain size characteristics along the wind direction, and discussed the interaction between sand drift and vegetation and its impact on landscape pattern. The results show that the change of the interaction mode between aeolian processes and vegetation alters the pattern of plants growth and surface erosion and deposition, resulting in obviously spatial heterogeneity in the downwind landscape. From bare land to uniformly distributed newborn Artemisia ordosica and shrubs, and then to patch distributed nebkhas, the vegetation coverage and sand cover thickness firstly increase and then decrease, the aerodynamic roughness rises continuously along the process, and the growth is the largest during the transition, while the sand transport rate and sediment particle size show a trend of first descent and then ascent, and the minimum value appears at the maximum of vegetation coverage and sand cover thickness. On the denudate plateau of the desert fringe, an appropriate amount of sand accumulation promotes the colonization and growth of the Artemisia ordosica at first, and the uniformly distributed shrubs further boosts sand deposition. However, when the accumulation thickness exceeds the sand resistant burial depth of Artemisia ordosica, it degenerates. Then, the shrub appears patchy distribution and the sand flow erodes between the interdune. Therefore, it can be understood that the landscape heterogeneity in the sandy area of the denuded plateau is the result of the synergy and inhibition of aeolian processes and vegetation. 参考文献 相似文献 引证文献

Nutrient Response Functions of Sorghum for Miesso District Central Rift Valley of Ethiopia

This study was executed to offer the basis for optimized profit from fertilizer use for sorghum yield and to determine robust crop nutrient response function and economic rate for the production of sorghum at Miesso Central Rift Valley of Ethiopia. Trails were conducted at six experimental sites, sorghum yield response to N and P fertilizers application and economically optimum rates of nitrogen (EONR) and phosphorus (EOPR) were evaluated on a vertisols within the semi-arid Miesso districts west Hararge zone of Oromia region. The nutrient rates in 2014 cropping season four levels of Nitrogen (N) alone, these levels with 20 kg·ha−1 Phosphorus (P) and without N, 69 kg·ha−1 N with three levels of P treatments including the zero control were evaluated. In 2015, cropping season similar rates of N alone, the same rate N with 20 kg·ha−1 P, 92 kg·ha−1 N with three rates of P including the zero control were evaluated. The treatments were arranged in a randomized complete block with three replications in factorial design. Nutrient responses of sorghum were determined using asymptotic quadratic plateau functions. The significantly highest nitrogen rate was 46 kg·ha−1 alone in 2014 season, which gave grain yield of 2.56 Mg·ha−1 with a maximum yield advantage of 43%. P rates in both seasons and combined (sites + seasons) were not significantly influenced sorghum yield. Nitrogen agronomic and partial factor productivity peaked at 23 kg N ha−1 but declined with increasing N rate. The EONR combined (sites + seasons) were 37, 45, 52 and 60 kg·ha−1 and for the profit to cost ratio (PCR) were 2.43, 3.65, 4.86 and 5.79 at difference cost to grain price ratios (CP) = 3.6, 2.3, 1.6 and 1.2 respectively at Miesso Ethiopia. Nitrogen application had economically profitable than P. The study concluded that the application of N at 37 or 60 kg N ha−1 to sorghum production could be economically profitable for those economically constrained farmers or economically not constrained farmers. Validation should be farther conducted on farmers’ fields for refining the results obtained.

Assessing Virtual Water of Agricultural Products in a Semi-Arid Zone Based on Copula Theory: A Case Study in the Fars Province, Iran

Assessing Virtual Water of Agricultural Products in a Semi-Arid Zone Based on Copula Theory: A Case Study in the Fars Province, Iran

Study of the Varietal Behavior of Eight Durum Wheat Genotypes Under Conditions in Haut Chéllif (Ain Defla, Algeria)

This study was conducted on five varieties of durum wheat of which 03 are native to the region of Ain Defla (Waha, Vitron, and Siméto), and 05 others introduced were studied during this test (NV25, NV26, NV27, NV28, NV29), to study their varietal behavior under natural climatic conditions in the semi-arid zone of Ain Defla, during the 2008/2009 campaign. The chosen experimental device is complete random blocks with 04 repetitions. The study focused on the phenological characteristics of the plant, such as plant height at maturity (cm), the number of tillers.m-2, the length of cob, the length of the pedoncule cob, as well as the development of the yield (biological and actual yield) and their components (number of fertile tillers plant-1, number of grains cob-1, 1000-grain weight (g), grain yield m-2). With phenological characteristics, the results show that some introduced varieties have a clear superiority compared to local varieties. Regarding the yield components, the results show that they are influenced by the variety factors and pedoclimatic adaptation conditions of the new varieties compared with the control varieties. Additionally, a difference between the biological and real yields was recorded to estimate the yield around 5% to 28% in the form of loss.

Diversity of Saxicolous Lichens along an Aridity Gradient in Central M閤ico

Lichens are symbiotic organisms that comprise a fungus and a photosynthetic partner wich are recognized as a good indicator of climate change. However, our understanding of how aridity affects the diversity of saxicolous lichens in drylands is still limited. To evaluate the relationship between saxicolous lichen diversity and aridity in a central México dryland, a geographical transect was established of 100 km to build an aridity gradient in the semiarid zone of the State of Querétaro, Mexico, comprising ten sampling sites with a 10 km separation. Species richness, abundance and diversity of soil lichen species were recorded using two sampling methods: the quadrat-intercept and the line-intercept method, to compare their performance in assessing soil lichen diversity in drylands. The number of species and Shannon diversity of saxicolous lichens were higher at intermediate values of the aridity index (AI = 0.10–0.34). Quadrat intercept and point intercept methods gave quite similar results, which means that the selected method does not influence the results in a significant way. This study confirms the role of saxicolous lichens as climate change indicators and reveals the importance of the sampling method selection in the evaluation of different parameters of soil lichen diversity in drylands.

Overview of dryland agriculture research and achievements in south west semi-arid zone of Uttar Pradesh

Overview of dryland agriculture research and achievements in south west semi-arid zone of Uttar Pradesh

Maize Yield Performance Under Planting Patterns and Row Spacing in Semi-Arid Zone of Pakistan-Mardan

Maize Yield Performance Under Planting Patterns and Row Spacing in Semi-Arid Zone of Pakistan-Mardan

Santa Ana Winds: Fractal-Based Analysis in a Semi-Arid Zone of Northern Mexico

A fractal analysis based on the time series of precipitation, temperature, pressure, relative humidity, and wind speed was performed for 16 weather stations located in the hydrographic basin of the Guadalupe River in Baja California, Mexico. Days on which the phenomenon known as Santa Ana winds occurs were identified based on the corresponding criteria of wind speed (≥4.5 m/s) and wind direction (between 0° and 90°). Subsequently, the time series was formed with data representing the days on which this phenomenon occurs in each of the analyzed weather stations. A time series was additionally formed from the days in which the Santa Ana winds condition does not occur. Hurst exponents and fractal dimension were estimated applying the rescaled range method to characterize the established time series in terms of characteristics of persistence, anti-persistence, or randomness along with the calculation of the climate predictability Index. This enabled the behavior and correlation analysis of the meteorological variables associated with Santa Ana winds occurrence. Finally, this type of research study is instrumental in understanding the regional dynamics of the climate in the basin, and allows us to establish a basis for developing models that can forecast the days of occurrence of the Santa Ana winds, in such a way that actions or measures can be taken to mitigate the negative consequences generated when said phenomenon occurs, such as fires and droughts.

Multiple Anthelmintic Resistance in Goat Farms from Semi-Arid Zone of Haryana

Multiple Anthelmintic Resistance in Goat Farms from Semi-Arid Zone of Haryana

Inheritance of plant height, straw yield and flag leaf area in MBB x Gaviota durum wheat (Triticum durum Desf.) cross

Plant height, straw mass and flag leaf area are recognized by physiologists as morphological markers of drought stress tolerance. Developing varieties intended for arid and semi-arid zones need to select for these traits. Understanding the genetic control of a given trait helps breeder to handle the segregating populations under study in a more efficient and consistent manner by choosing the best breeding method available to realize significant genetic advance. For this purpose, six generations: parents, F1, F2, BC1, BC2, derived from MBB x ‘Gaviota’ durum wheat (Triticum durum Desf.) cross were grown to investigate the nature of gene action involved in the inheritance pattern of the three traits. The results indicated that the six-parameter model fitted the best the data related to the variability present in the generation means of the studied traits. Generation mean analysis indicated that non-allelic interactions were important factors controlling the expression of these characters with complementary type of gene action governing FLA and STW inheritance. High heritability estimates, moderate to high expected responses to selection, significant genetic correlations with grain yield and greater role of non-additive effects in controlling the inheritance of the three studied traits suggested that breeding methods exploiting both fixable and non-fixable components be applied to break unfavorable linkage and to accumulate useful genes in the base population, followed by mono-trait or index based selection in late advanced generations.

Global patterns and ecological implications of diurnal hysteretic response of ecosystem water consumption to vapor pressure deficit

Increasing vapor pressure deficit (VPD) has led to widespread reductions in vegetation carbon uptake by stomatal hydraulic regulation. The response of vegetation to VPD is therefore paramount in the global water and carbon cycle, and draws worldwide attention. However, the hysteretic response of ecosystem water consumption to VPD, although widely reported across the world, is still lack of systematic and consistent research on its global patterns and ecological implications. Based on a newly developed hourly dataset of land-atmosphere fluxes, this study finds that hysteresis increases with climatic aridity and long hysteresis mainly occurs in water-limited areas; the hysteretic response of water consumption to VPD for woody ecosystems is shorter than that for the herbaceous ecosystems; interestingly, gross primary productivity (GPP) increases with hysteresis at the high hysteresis ends in dry environments (dry-humid, semi-arid and arid zones), which might suggest an existence of drought-adapting mechanisms of vegetation growth that is relevant to hysteresis but overlooked before. This study provides important information for projecting future shifts of ecosystem functions under increasing atmospheric dry stress.