Arid zone island hopping: the impact of dispersal on endemism in hydraenid beetles (Coleoptera: Hydraenidae) found in isolated desert springs

2019 ◽  
Vol 58 (4) ◽  
pp. 886-896
Author(s):  
Matthew L DeBoo ◽  
Nicholas P Murphy ◽  
Andrew D Austin ◽  
Chris H S Watts ◽  
Michelle T Guzik
Keyword(s):  
Arid Zone ◽  
Desert Springs ◽  
The Impact

scholarly journals The demography of desert Australia

2008 ◽  
Vol 30 (1) ◽  
pp. 29 ◽  
Author(s):  
Dominic Brown ◽  
John Taylor ◽  
Martin Bell
Keyword(s):  
Economic Policy ◽  
Arid Zone ◽  
Policy Implications ◽  
Population Projections ◽  
Research Centre ◽  
Arid Zones ◽  
Demographic Information ◽  
The Impact ◽  
First Time ◽  
Semi Arid

In recent years, with the formation of organisations such as the Desert Knowledge Cooperative Research Centre, social science interest in the Australian desert has re-surfaced with a research emphasis that is focused on creating sustainable futures for the region. One consequence of this is a demand for detailed demographic information to allow an assessment of different quanta of need in social and economic policy, and for assessment of the impact of these in environmental policy. However, demographic analysis on human populations in the desert to date has attracted very little research attention. In this paper we begin to address this lack of analysis by focusing on the populations, both aboriginal and non-aboriginal, of the arid and semi-arid zones of Australia. We extend earlier analysis by including for the first time demographic information on the semi-arid as well as the arid zone to establish the spatial pattern of population growth within the whole desert area drawing attention to the resulting settlement structure as an outcome of prevailing social, cultural and economic conditions. By examining population structure and demographic components of population change we also present for the first time population projections for the semi-arid zone and, therefore, in combination with the arid zone, for the entire Australian desert. All of this provides a basis for considering social and economic policy implications and the nature of underlying processes that drive change in this region.

scholarly journals Climatic effects on breeding grounds are more important drivers of breeding phenology in migrant birds than carry-over effects from wintering grounds

2013 ◽  
Vol 9 (6) ◽  
pp. 20130669 ◽  
Author(s):  
Nancy Ockendon ◽  
Dave Leech ◽  
James W. Pearce-Higgins
Keyword(s):  
Clutch Size ◽  
Arid Zone ◽  
Laying Date ◽  
Breeding Phenology ◽  
Spring Temperature ◽  
Climatic Effects ◽  
Long Distance ◽  
Breeding Grounds ◽  
Carry Over ◽  
The Impact

Long-distance migrants may be particularly vulnerable to climate change on both wintering and breeding grounds. However, the relative importance of climatic variables at different stages of the annual cycle is poorly understood, even in well-studied Palaearctic migrant species. Using a national dataset spanning 46 years, we investigate the impact of wintering ground precipitation and breeding ground temperature on breeding phenology and clutch size of 19 UK migrants. Although both spring temperature and arid zone precipitation were significantly correlated with laying date, the former accounted for 3.5 times more inter-annual variation. Neither climate variable strongly affected clutch size. Thus, although carry-over effects had some impact, they were weaker drivers of reproductive traits than conditions on the breeding grounds.

scholarly journals Impact of Intercropping Sorghum and Okra on the Incidence of Flea Beetles of Okra Podagrica spp in Dalwa, Maiduguri Semi-Arid Zone of Nigeria

2014 ◽  
Vol 14 ◽  
pp. 51-58
Author(s):  
M.M. Degri ◽  
I.B. Richard
Keyword(s):  
Field Experiments ◽  
Insect Pests ◽  
Arid Zone ◽  
Flea Beetle ◽  
Fruit Weight ◽  
Fruit Yield ◽  
Leaf Damage ◽  
The Impact ◽  
Fruit Formation ◽  
Semi Arid

Field experiments were conducted at faculty of Agriculture teaching and research farm, university of Maiduguri in 2010 and 2011 rainy seasons. The aim was to investigate the impact of intercropping sorghum with okra on the incidence of flea beetle of okra (Podagrica spp) in the semi-Arid zone of Nigeria. The results showed that sole crop okra suffered flea beetle attack which affected its growth, fruit formation, fruit weights and fruit yield. Intercropping okra with sorghum significantly reduced the flea beetle populations, leaf damage caused by Podagrica spp (Coleoptera: Chrysomelidae). While increasing number of leaves for photosynthetic activities, plant height, fruit formation, fresh fruit weight and total fruit yield. The study concluded that okra intercropping at 1:1, 1:2 and 2:2 are the most efficient and productive intercrop systems in flea beetle management. Okra intercropping with cereal sorghum was found to be good for sustainable agriculture and organic farming in Nigeria due to its numerous advantages, particularly with respect to insect pests’ control.

scholarly journals Effect of Fires on Certain Properties of Forest Soils in Western Algeria

2020 ◽  
Vol 23 (3) ◽  
pp. 111-117
Author(s):  
Ayoub Allam ◽  
Amine Habib Borsali ◽  
Abdelkrim Kefifa ◽  
Mohamed Zouidi ◽  
Raphael Gros
Keyword(s):  
Forest Soils ◽  
Forest Fires ◽  
Arid Zone ◽  
Chemical Properties ◽  
Biological Properties ◽  
Basal Respiration ◽  
Arid Ecosystems ◽  
Control Zone ◽  
The Impact ◽  
Semi Arid

AbstractNatural disturbances, such as forest fires, cause significant changes in the structure and functioning of semi-arid ecosystems. After such disturbances, the impact on the soil ecosystem in its entirety is misunderstood. In this study, two years after the last fire, changes in the physicochemical and biological properties of Aleppo pine forest soils in the semi-arid zone were observed. Among all physical properties analysed, only the soil moisture remained significantly lower in the burnt zone in contrast to control zone. Considering the chemical properties, the only negatively affected parameter is the rate of organic matter. In terms of biological properties, results showed that the fire caused a significant decrease in soil microorganisms by decreasing basal respiration and microbial biomass. Conversely, the metabolic quotient recorded higher values in the fire zone than in the control zone. These results indicate that microbial communities in semi-arid soils, already stressed by climatic hazards, are very sensitive to the passage of even low-intensity fires.

scholarly journals Correlative Evaluation of the Impact of Adaptive Plant Morphology on Bioactive Accumulation Based on Micro-Morphological Studies in Andrographis serpyllifolia (Rottler ex Vahl) Wight

2017 ◽  
Vol 9 (2) ◽  
pp. 263-273
Author(s):  
Suma KRISHNASWAMY ◽  
Bopaiah A. KUSHALAPPA
Keyword(s):  
Deductive Reasoning ◽  
Arid Zone ◽  
High Stress ◽  
Plant Morphology ◽  
Accurate Identification ◽  
Peninsular India ◽  
Morphological Studies ◽  
Wide Range ◽  
Leaf Surfaces ◽  
The Impact

Does the adaptive plant morphology actually hint at its potential bioactive profile? To understand and decipher this, a micro-morphological investigation was conducted on an arid zone plant. Andrographis serpyllifolia (Rohl.ex.vahl.) Wight is a slightly bitter, acrid endemic herb with fair history of ethno-botanical use among different tribes of peninsular India. A. serpyllifolia was a highly evolved geophyte well-suited for high survivability in extremely harsh terrain. This plant was found to grow and perpetuate successfully under high-stress conditions of water deficit, high soil and atmospheric temperatures, poor nutrition and constant threat from herbivores. Under such circumstances, this plant possessed the potential to develop morphological adaptations that produce and accumulate a wide range of phytochemicals that could preserve, protect and defend its plant body. The twin objectives of this study were to investigate the micro-morphological features and their functional advantage that enabled the plant to flourish in adverse conditions and interpret by deductive reasoning, the potential phytochemical array of this plant given the observed features. Scanning electron microscope was used to explore surface morphologies of various vegetative and floral parts. Key findings of this micro-morphological study were presence of numerous diacytic stomata on both adaxial and abaxial leaf surfaces, abundant glandular sessile trichomes on abaxial leaf surfaces, reticulate pollen ornamentation with echinate sulcus outlined with smooth morus and deeply reticulate, highly pitted spermoderm or seed testa reminiscent of human brain. These three features may serve as pharmacognostic markers aiding in accurate identification and quality control of this herb.

Factors controlling primary productivity in a wet–dry tropical river

2013 ◽  
Vol 64 (7) ◽  
pp. 585 ◽  
Author(s):  
S. J. Faggotter ◽  
I. T. Webster ◽  
M. A. Burford
Keyword(s):  
Algal Blooms ◽  
Algal Biomass ◽  
Arid Zone ◽  
River System ◽  
Dry Season ◽  
Trophic Levels ◽  
Nutrient Inputs ◽  
Tropical River ◽  
Algal Production ◽  
The Impact

Algal production in rivers fuels foodwebs, and factors controlling this production ultimately affect food availability. Conversely, excessive algal production can have negative effects on higher trophic levels. The present study examined permanent waterholes in a disconnected wet–dry tropical river to determine the controls on algal production. Primary production in this river system was high compared with arid-zone and perennially flowing tropical rivers. Phytoplankton biomass increased over the dry season but this appeared to be because waterhole volume decreased, due to evaporation. Nitrogen (N) was the key limiting nutrient for phytoplankton, with rapid N turnover times, depletion of particulate 15N-nitrogen reflecting increasing N fixationover the dry season, and N stimulation in phytoplankton bioassays. The waterholes were shallow, providing sufficient light for accumulation of benthic algal biomass. Exclosure experiments were also conducted to determine the impact of top–down control on benthic algal biomass, with no evidence that exclusion of fish and crustaceans increased benthic algal biomass. The shallow off-channel waterhole in our study had substantially higher concentrations of nutrients and chlorophyll a than did the on-channel waterholes. This suggests that future anthropogenic changes, such as increased water extraction and increased nutrient inputs, could make the waterholes more vulnerable to deteriorating water quality, such as e.g. algal blooms, low concentrations of dissolved oxygen.

Analysis on the Water Resource Bearing Capacity of Arid Zone – In Kashgar Zone for Example

2014 ◽  
Vol 955-959 ◽  
pp. 3761-3765
Author(s):  
Hong Mei Chen ◽  
Qing Li
Keyword(s):  
Bearing Capacity ◽  
Water Resource ◽  
Arid Zone ◽  
Evaluation Model ◽  
Analytic Hierarchy ◽  
Index Evaluation ◽  
The Impact ◽  
Hierarchy Process ◽  
Resource Capacity ◽  
Resource Factor

As an economic development area, Kashgar’s water resource bearing capacity had become the key of the development on economy and society. In the view of comprehensive systematic theory, this paper, based on the theory of resource factor flow, adopted fuzzy analytic hierarchy process to establish a comprehensive index evaluation model of water resource bearing capacity. Finally, this paper proposed the factors’ extent of the impact on water resource capacity in Kashgar area.

scholarly journals On the Optimisation of Urban form Design, Energy Consumption and Outdoor Thermal Comfort Using a Parametric Workflow in a Hot Arid Zone

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4026
Author(s):  
Yasser Ibrahim ◽  
Tristan Kershaw ◽  
Paul Shepherd ◽  
David Coley
Keyword(s):  
Energy Consumption ◽  
Thermal Comfort ◽  
Urban Form ◽  
Energy Use ◽  
Arid Zone ◽  
Morphological Characteristics ◽  
Outdoor Thermal Comfort ◽  
Design Parameters ◽  
Overall Performance ◽  
The Impact

The recent reports from the Intergovernmental Panel on Climate Change (IPCC) urge for the reconceptualization of our design of the urban built environments. However, current efforts to integrate urban environmental assessment into practice in Egypt are proving insufficient. This paper utilises the Ladybug tools simulation plugins to investigate the impact of changing the morphological characteristics of three-block typologies (scattered, linear and courtyard) and their associated parameters to understand their multidimensional relationship with environmental conditions, outdoor thermal comfort and energy use intensity. This study based in Cairo, Egypt, considers 3430 hypothetical geometrical configurations comprising of a variety of design parameters and indicators. The results show a strong correlation between the design parameters and the combined performance of thermal comfort and energy consumption (R2 = 0.84), with urban density having the strongest impact on both thermal comfort and energy use (R2 = 0.7 and 0.95, respectively). The design parameters exhibited a consistent impact on the different typologies, albeit with varying magnitude. Compact and medium-density urban forms are shown to elicit the best overall performance, especially for ordinal orientations (e.g., ~45°) across all typologies. Compact high-density scattered forms are favoured when considering thermal comfort, while courtyards outperform other typologies when considering energy efficiency and overall performance.

scholarly journals Influence of main tillage methods on barley yield in the Lower Volga region

2020 ◽  
pp. 43-47
Author(s):  
Dmitriy Pavlovich Polyakov ◽  
Andrey Vladimirovich Tyutyuma
Keyword(s):  
Field Experiments ◽  
Arid Zone ◽  
Spring Barley ◽  
Arable Land ◽  
Resource Saving ◽  
Forage Crops ◽  
Climate Conditions ◽  
The North ◽  
Harsh Climate ◽  
The Impact

Light-chestnut soils of the arid zone of the North of the Astrakhan region, even if all the standards of agricultural engineering are observed, are characterized by unfavorable agrochemical and water-physical properties for most crops. To successfully solve the problems associated with increasing adaptation of zonal agriculture to harsh climate conditions, it is necessary to search for new resource-saving technologies. The purpose of the work is to identify the impact of resource-saving methods of basic soil cultivation on the yield of spring barley in the semi-desert conditions of the North of the Astrakhan region. The organization of field experiments, observations and laboratory analyses were carried out according to the method of conducting field experiments Dospekhov B. A. and Guidelines for conducting field experiments with forage crops (research Institute of feed). The results of the conducted field experiments and laboratory studies give reason to speak about the feasibility of using a resource-saving soil-cultivating organ ROPA in the zone of unstable moisture in the North of the Astrakhan region. Loosening this unit contributes to an increase of 25% of the total spring stock of soil moisture. The introduction of this deep tillage (H=0.40-0.45 m) and tools for its implementation (ROPA) allows you to get in the rain-fed conditions of the arid zone of the North of the Astrakhan region from one hectare of arable land to 1.24 tons of barley Vakula and 1.30 tons of barley Ratnik.

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