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Under the global crisis of energy shortage and environmental pollution, the climate responsive strategies used in vernacular buildings have attracted much attention for their potential to reduce energy consumption and carbon emissions. However, the relationships between these traditional climatic strategies were not precisely perceived, which may cause the inapplicability of these strategies for contemporary rural houses. In this paper, taking the Turpan vernacular buildings in arid region of China, the climate responsive strategies of buildings in the most significant periods such as the Gaochang period (before 1318), the Khanate and Republican period (1318–1949), the Modern period (1949–2010), and the Contemporary period (2011–present) were summarized. In addition, two different types of climatic strategies organizations, namely multilayer spaces and integrated building envelopes, were identified based on the temperature difference measurement and comparative analysis. The assessment of thermal performance of the organizations was conducted by the methodology of software simulation. Furthermore, the applicability of the organizations in rural areas was discussed, and a new combined organization was proposed. Consequently, this study can contribute to provide the main approaches for climatically responsive rural houses. [ABSTRACT FROM AUTHOR]

Livestock production in drylands requires consideration of the ecological applications of ecohydrological redistribution of water. Intensive cattle trampling and the associated increase of surface runoff are common concerns for rangeland productivity and sustainability. Here, we highlight a regional livestock production system in which cattle trails and trampling surrounding an artificial impoundment are purposely managed to enhance redistribution and availability of water for cattle drinking. Based on literature synthesis and field measurements, we first describe cattle production systems and surface water redistribution in the Dry Chaco rangelands of South America, and then develop a conceptual framework to synthesize the ecohydrological impacts of livestock production on these ecosystems. Critical to this framework is the pioshere—a degraded overgrazed and overtrampled area where vegetation has difficulties growing, usually close to the water points. The Dry Chaco rangelands have three key distinctive characteristics associated with the flat sedimentary environment lacking fresh groundwater and the very extensive ranching conditions: (1) cattle drinking water is provided by artificial impoundments filled by runoff, (2) heavy trampling around the impoundment and its adjacent areas generates a piosphere that favors runoff toward the impoundment, and (3) the impoundment, piosphere, and extensive forage areas are hydrologically connected with a network of cattle trails. We propose an ecohydrological framework where cattle transit and trampling alter the natural water circulation of these ecosystems, affecting small fractions of the landscape through increased runoff (compaction in piosphere and trails), surface connectivity (convergence of trails to piosphere to impoundment), and ponding (compaction of the impoundment floor) that operate together making water harvesting and storage possible. These effects have likely generated a positive water feedback on the expansion of livestock in the region with a relatively low impact on forage production. We highlight the role of livestock transit as a geomorphological agent capable of reshaping the hydrology of flat sedimentary rangelands in ways that can be managed positively for sustainable ranching systems. We suggest that the Dry Chaco offers an alternative paradigm for rangelands in which cattle trampling may contribute to sustainable seminatural production systems with implications for other dry and flat rangelands of the world. [ABSTRACT FROM AUTHOR]

• The habitat template as the approach to design sustainable green roofs in Lima, Peru. • Some Lomas systems have similar edaphic conditions as extensive green roofs. • Lomas herb species with succulence and clonal capacity are ideal for green roofs in Lima. • Shrubs may fit better on semi-intensive green roofs due to their deep roots and erect growth. • Green roofs can function as alternative habitats for endangered Lomas species. Ongoing urbanisation and climate change threaten urban green (UG) spaces in Lima, exacerbated by conventional design and management methods. Extensive green roofs (GRs) are a promising alternative in Lima's context as they provide numerous benefits and are adapted to arid conditions. This study aimed to develop sustainable GRs in Lima by using the Lomas ecosystems as a habitat template. We analysed abiotic conditions and plant traits of Lomas communities and compared them with those of GRs. We compared species composition and edaphic properties from five Lomas around Lima with those of arid GR systems. Lomas and GR species were further classified into functional groups based on their functional traits. Amancaes, Lachay and Villa Maria del Triunfo (VMT) have soils with similar characteristics as arid GRs, and the most suited Lomas species were found there. The 'herb functional group', consisting of herbs with succulence and clonal capacity, may be suitable for GRs due to arid adaptations and creeping and clumping growth patterns. Given the endangered status of several Lomas species within this group, introducing them to GRs in Lima offers a conservation opportunity, helping their survival and establishing urban complementary habitats. Shrub species such as Heliotropium , Atriplex , Croton , and Trixis are the most frequent shrubs in Lomas and are crucial for preserving the structure and biodiversity of the ecosystem. However, the 'shrub functional group' may be better suited for semi-intensive GRs due to their deeper root systems and erect growth. The habitat template approach can aid biodiversity conservation by incorporating threatened and endemic Lomas species into GR systems. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin de la Societe Zoologique de France is the property of Societe Zoologique de France and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Display omitted] • Shallow tributary regions (<15 m depth) were the main source of GHGs. • Methane dominated the CO 2 equivalent emissions throughout the reservoir. • GHG emissions per MWh vary dramatically with reservoir water level. • GHG emissions per MWh were low compared to other conventional energy sources. Reservoirs in arid regions often provide critical water storage but little is known about their greenhouse gas (GHG) footprint. While there is growing appreciation of the role reservoirs play as GHG sources, there is a lack of understanding of GHG emission dynamics from reservoirs in arid regions and implications for environmental policy. Here we present initial GHG emission measurements from Lake Powell, a large water storage reservoir in the desert southwest United States. We report CO 2 -eq emissions from the shallow (< 15 m) littoral regions of the reservoir that are higher than the global average areal emissions from reservoirs (9.4 vs. 5.8 g CO 2 -eq m−2 d−1) whereas fluxes from the main reservoir were two orders of magnitude lower (0.09 g CO 2 -eq m−2 d−1). We then compared our measurements to modeled CO 2 + CH 4 emissions from the reservoir using four global scale models. Factoring these emissions into hydropower production at Lake Powell yielded low GHG emissions per MWh−1 as compared to fossil-fuel based energy sources. With the exception of one model, the estimated hydropower emissions for Lake Powell ranged from 10−32 kg CO 2 -eq MWh−1, compared to ∼400−1000 kg CO 2 -eq MWh−1 for natural gas, oil, and coal. We also estimate that reduced littoral habitat under low water levels leads to ∼50% reduction in the CO 2 equivalent emissions per MWh. The sensitivity of GHG emissions to reservoir water levels suggests that the interaction will be an important policy consideration in the design and operation of arid region systems. [ABSTRACT FROM AUTHOR]

Studying fish communities in extreme habitats is important to better understand the variation in their ranges under climatic scenarios or anthropogenic pressure. In particular, the mangroves in Baja California Sur occupy the northernmost distribution range under two extreme conditions (temperate waters and arid weather). In this context, the aim of the presently reported study was to analyze the functional characteristics of ichthyofauna in two localities, La Paz Bay (BP) and Almejas Bay (BA), which are also located in different ecoregions. For both bays, the composition and frequency values were compiled from monthly samples and the literature. Eleven functional traits were assessed from the morphology of every fish species. Functional indices (Richness, Evenness, Divergence, and Originality) were used to evaluate different aspects of the community structure. A total of 83 species were found at both sites, with 54 in BP and 50 in BA. In BP, six species were residents, eight were temporal visitors, and 36 were occasional visitors. In BA, six species were residents, 15 species were temporal visitors, and 33 were occasional visitors. At both sites, 12% of the species were permanent residents; BA had a higher percentage of temporal residents (27%), while BP had a higher percentage of occasional visitors (72%). The functional analysis detected communities with specialized traits, but in comparison to BP, BA had higher evenness in the community structure. Although greater structural complexity was expected in the community during the warm months, because of the increase in richness and attributes, BA had higher values during the cold months, which was probably because the area is a transition zone and the fish communities are adapted to colder climates. In comparison to BA, BP had higher originality values, and colder months presented higher values than warmer months. Although the mangrove sites had the same northern most latitudinal limits and both had extreme conditions compared to those in mangroves in tropical environments, the fish communities differed in their composition, frequency, and functionality with more extreme functional traits in colder weather than in warmer weather. [ABSTRACT FROM AUTHOR]

A lack of water quality monitoring stations in arid regions makes it difficult to estimate the exact level of water pollution. Satellite technology is crucial for monitoring the water quality of salt lakes, but due to the diversity of terrestrial water bodies, it is challenging to establish relationships between lake water color parameters and remote sensing reflectance. This study aims to evaluate the reliability of the colored Quasi-Analytical Algorithm Dissolved Organic Matter (QAA-CDOM) model over Ebinur Lake. The absorption coefficient measured on May 19, 2021 was used to analyze the optical properties of Ebinur Lake. The findings show that the QAA-CDOM model performed well in estimating the absorption coefficient of CDOM at 443 nm, with the r2 and RMSE values of 0.69 and 0.12 m−1, respectively. The Landsat 8 OLI data and QAA-CDOM model were then used to derive the spatial-temporal characteristics of the CDOM concentration over Ebinur Lake from 2014 to 2021. The concentration of CDOM changes significantly across time and space, ranging from 0 to 2.5 m−1, with the lowest concentration in May and the highest in August. The central region of the lake has a lower concentration of CDOM than the other regions due to the reflectance of the shallow parts of the lake. This study clarified the inherent optical characteristics of saline lakes and proved the applicability of using the QAA-CDOM model to monitor surface water quality in arid regions of China. This research may be useful for future analyses of the carbon cycle calculations in salt lakes in arid regions. • Explore the optical characteristics of Lake. • Validate model's applicability. • Analyze CDOM change. [ABSTRACT FROM AUTHOR]

Highlights • Declining forage production from shrublands dominates the perspective of stakeholders. • While shrublands provide other ecosystem services, they are rarely considered. • Shrub removal generated trade-offs between ecosystem services. • Sustainable land use should minimize trade-offs between different ecosystem services. • Sustainability requires socio-economical, not merely ecological understanding. Abstract In many shrub-encroached lands, livestock grazing is the dominant land-use type which shapes stakeholders' perspective on single ecosystem service provision (i.e., forage production). Although recent ecological studies suggested otherwise, recognition of multiple ecosystem services from shrublands is rarely translated into policy, likely due to the lack of robust scientific evidence on trade-offs between ecosystem services following shrub removal. Based on meta-analysis from global publications, we found that while shrub removal increased forage provision, such effect was generally short-lived (˜5 years). At the same time, shrub removal also increased bare soil, decreased soil nutrients and soil organic carbon, which potentially reduced erosion control and nutrient cycling service. These trade-offs tended to be more prominent with increasing disturbance intensity (i.e., higher shrub removal frequencies or switching from single to multiple shrub removal methods). To encourage adaptation to the provisioning of multiple ecosystem services from shrublands, we provided a framework on how to value such landscapes, including the estimated monetary values that could be generated from maintaining them. Since there will be a time-lag until most monetary values appear, initial incentives may be necessary to encourage the adoption of conservation practices, in addition to efforts to increase society awareness (e.g., eco-labelling, alternative food networks or social media) on multiple ecological benefits from shrublands and investment to provide capacity building for pastoralists. [ABSTRACT FROM AUTHOR]

Highlights • We present for the first-time vegetation patterns with the shape of spirals. These spirals were observed in the north of Chile. • The existence of spirals is based on an interaction between the dynamics of plants and grazing. • We propose excitability as the mechanism that explains the growth of these patterns. • We develop a simple mathematical model that reproduces the field observations at the quantitative level. Abstract When plant communities suffer the stress of limited resources, for instance adverse environmental conditions such as extreme aridity, the spatial homogeneity of the biomass is lost and self-organized patterns may arise. Here, we report the observation of spiral-shaped patterns in the biomass of grass (genus deyeuxia), under highland arid conditions in the north of Chile. The spiral arms are a few meters long and a few centimeters wide. These dynamic structures are observed in the grazing area of an herbivore member of the South American camelids, the vicuna, on the border of highland wetlands. These spirals cannot be explained by the well-established mathematical models which describe other vegetation patterns (that emerge from a Turing-type of instability) such as stripes, rings, or fairy circles. We attribute the formation of spirals to the coupling between the growth of vegetation in semiarid regions and the grazing of vicunas. The mathematical analysis of this coupling reveals an excitable behavior, i.e. small perturbations of the equilibrium generate large trajectories before coming back, that is the origin of the spirals. [ABSTRACT FROM AUTHOR]

Hydrodynamics and associated environmental processes have always been of major concern to coastal-dependent countries, such as Kuwait. This is due to the environmental impact that accompanies the economic and commercial activities along the coastal areas. In the current study, a three-dimensional numerical model is utilized to unveil the main dynamic and physical properties of Kuwait Bay during the critical season. The model performance over the summer months (June, July and August 2012) is assessed against comprehensive field measurements of water levels, velocity, temperature and salinity data before using the model to describe the circulation as driven by tides, gravitational convection and winds. The results showed that the baroclinic conditions in the Bay are mainly determined by the horizontal salinity gradient and to much less extent temperature gradient. The gradients stretched over the southern coast of the Bay where dense water is found at the inner and enclosed areas, while relatively lighter waters are found near the mouth of the Bay. This gradient imposed a reversed estuarine circulation at the main axis of the Bay, particularly during neap tides when landward flow near the surface and seaward flow near the bed are most evident. The results also revealed that the shallow areas, including Sulaibikhat and Jahra Bays, are well mixed and generally flow in the counter-clockwise direction. Clockwise circulations dominated the northern portion of the Bay, forming a sort of large eddy, while turbulent fields associated with tidal currents were localized near the headlands. [ABSTRACT FROM AUTHOR]

The arid southeastern Iberian Peninsula is a unique region in which conservation and human development have coexisted and coevolved over many decades. However, conflicts between economic development and conservation have generated increasing concern due to the rapid expansion of greenhouse horticulture and the abandonment of rural and mountainous areas. Human decisions regarding land use management have affected the status of ecosystems and therefore the ecosystem services supply. We identified four land use-land cover changes that summarize the most common management decisions. These include greenhouse horticulture expansion, urban intensification, rural abandonment, and conservation actions, which occur through protected area declarations. This study aims to explore the social relevance of land use-land cover changes on the delivery of eight key services provided by Spanish arid ecosystems as follows: provisioning services related to intensive and traditional agriculture, regulating services associated with water regulation, climate regulation, air quality and erosion control, and cultural services linked to local identity and tourism. Through 402 face-to-face questionnaires, we analyzed the arguments for and against these four land use-land cover types. We also assessed their impact on ecosystem services and the social importance and vulnerability of ecosystem services. We found significant differences in the social perception of the positive and negative impacts of land use types on ecosystem services. The sample population recognized the negative impacts of greenhouse horticulture on regulating services that are, in terms of water regulation, essential for the sustained delivery of final provisioning services related to agricultural activities. Overall, traditional agriculture and tourism are recognized as the most important services. A controversy between the two opposite models of territorial development – urban development and nature conservation – highlights the need to promote new strategies of land management. Finally, we discuss the usefulness of this approach to understand the arguments affecting the promotion of land use-land cover changes and to visualize the ecosystem service trade-offs under different management strategies. [ABSTRACT FROM AUTHOR]

A fire through hummock grassland in Western Queensland adjacent to a gas pipeline trench resulted in a 650% increase in the number of animals that were recovered from the trench in the seven days following the fire compared to the seven days prior. Those lizard species th at shelter within spinifex or grass clumps, such as Tiliqua multifasdata, Ctenotus leonhardii, C. pantherinus, Lialis burtonis and Strophurus elderi had the largest increases, and the mammals Pseudomys desertor and Planigale tenuirostris showed similar increases. Species th at typically shelter in burrows or ground cracks showed a decline in numbers recorded following the fire. Seven days after the fire event 91 animals were removed from the last 3km of open trench. However, no animals were ever observed moving across the burnt areas during the day. So where they came from and when they travelled remains unanswered. [ABSTRACT FROM AUTHOR]

Groundwater levels in arid environments are dropping worldwide due to human extraction, and precipitation events are predicted to become rarer and more intense in many arid areas with global climate change. These changes will likely alter both primary productivity and plant-soil nutrient cycles. To better understand the nature of such alterations, we examined effects of groundwater availability on plant-soil nitrogen (N) cycling in areas invaded by the N-fixing phreatophyte, Prosopis pallida, on the dry leeward coast of Hawai'i Island. Our aims were to quantify effects of groundwater availability to P. pallida on rates of litterfall N inputs and accretion in soils and to quantify effects of groundwater availability on N mineralization and leaching rates of inorganic N under natural rainfall conditions and simulated rain events. Stem water δ18O values indicate that P. pallida trees in lowland plots accessed shallow groundwater, while in upland plots they relied solely on rainfall. During drought periods, P. pallida at upland plots experienced water stress, evidenced by lower stem water potentials, higher water-use efficiency, and lower predawn photosynthetic performance than at lowland plots. Prosopis pallida basal area was 5.3 times greater at lowland plots, and these plots exhibited 17 times higher carbon (c), 24 times higher N, and 35 times higher phosphorus (P) additions via litterfall, indicating that productivity of this phreatophyte was decoupled from rainfall where groundwater was present. Total N mass in soils was 4.7 times greater where groundwater was accessible, supporting the case that groundwater access increased N2 fixation at a stand level. In contrast, N mineralization and leaching losses from soils, though substantially greater in lowland relative to upland areas, were strongly controlled by rainfall. Results provide clear examples of how invasive species with particular functional attributes (i.e., N-fixing phreatophytes) exploit otherwise inaccessible resources to dramat-ically alter the functioning of the systems they invade and how anthropogenic changes to hydrological processes can also alter ecosystem-level impacts of biological invasions. Results also illustrate a mechanism by which regional groundwater drawdown may reduce soil nutrient accretion and availability in arid regions. [ABSTRACT FROM AUTHOR]

Highlights: [•] We modeled carbon dynamics in dryland grasslands in Xinjiang, China under varied grazing intensity. [•] Grassland ecosystems in Xinjiang acted as a net carbon source, 8.98TgCyear−1for the period 1979–2007. [•] An over-compensatory effect in net primary productivity (NPP) and vegetation/soil carbon was observed when grazing intensity was lower than 0.40head/ha. [•] Grazing resulted in a net carbon release of −23.45gCm−2 yr−1, which equaled 0.36Pg in Xinjiang in the last 29 years. [Copyright &y& Elsevier]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses the study on comparative impact of two worm management schemes, based on worm profile and flock performance, in naturally infected sheep flocks in Rajasthan, India from May 2004 to March 2012, for gastrointestinal strongyles and production performance of flock. The study found almost similar monthly incidence and intensity of strongyle nematodes among flocks given strategic or conventional anthelmintic treatment. Higher magnitude of infection was shown during monsoon.

Micronutrients are important components of plant production. Due to the high pH and calcium carbonate contents, micronutrient deficiencies are widespread in the soils of arid regions. The purpose of this study was to find out the relationships between spatial distribution of soil properties and available micronutrients (Zn, Cu, Fe, and Mn) in a highly saline arid environment. Soils were collected from a 2650 ha field which was divided into square sub-blocks, with 400 m spacing in x and y directions, for sampling procedure. One hundred fifty one soil samples were collected from 0-30 cm of soil surface, and diethylenetriamine penta-acetic acid DTPA-extractable micronutrients Zn, Cu, Fe, and Mn and some of physical and chemical characteristics were determined. Geostatistical techniques were employed to determine the spatial variability of micronutrients. Extractable micro nutrient contents varied from 0.59 to 5.49 mg kg-1 for Fe, from 0.04 to 0.61 mg kg-1 for Zn, from 1.54 to 14.01 mg kg-1 for Cu and from 0.12 to 2.09 mg kg-1 for Mn. The correlations between extractable contents of Fe and Cu were not significant but all the others were significantly important (P<0.01) that was also clearly shown in the spatial distribution maps. The results of semivariance analysis showed that the available Fe and Mn were spatially correlated at a larger distance of 5940 and 5889 m, and the available Cu and Zn were at a shorter distance of 1350 and 1740 m, respectively. Concentrations except Mn were relatively low in the northern part of the study area where the sand content was high. Understanding how plant-available soil micronutrients vary across the land enables to determine the rational management of micronutrient fertility. [ABSTRACT FROM AUTHOR]

Abstract: A three-year study was conducted to evaluate the effects of different irrigation regimes with saline water on soil salinity, yield and water productivity of carrot as a fall-winter crop under actual commercial-farming conditions in the arid region of Tunisia. Carrot was grown on a sandy soil and surface-irrigated with a water having an ECi of 3.6dS/m. For the three years, a complete randomized block design with four replicates was used to evaluate five irrigation regimes. Four irrigation methods were based on the use of soil water balance (SWB) to estimate irrigation amounts and timing while the fifth consisted of using traditional farmers practices. SWB methods consisted in replacement of cumulated ETc when readily available water is depleted with levels of 100% (FI-100), 80% (DI-80) and 60% (DI-60). FI-100 was considered as full irrigation while DI-80 and DI-60 were considered as deficit irrigation regimes. Regulated deficit irrigation regime where 40% reduction is applied only during ripening stage (FI-DI60) was also used. Farmer method (Farmer) consisted in giving fixed amounts of water (25mm) every 7days from planting till harvest. Results on carrot production and soil salinization are globally consistent between the three-year experiments and shows significant difference between irrigation regimes. Higher soil salinity in the root zone is observed at harvest under DI-60 (3.1, 3.4, 3.9dS/m, respectively, for the three years) and farmer irrigation (3.3, 3.6, 3.9dS/m) treatments compared to FI-100 treatment (2.3, 2.6 and 3.1dS/m). Relatively low ECe values were also observed under FI-DI60 and DI-80 treatments with respectively (2.7, 3, 3.5dS/m) and (2.5, 2.9, 3.3dS/m). ECe values under the different irrigation treatments were generally lower than or equal to the EC of irrigation water used. Rainfall received during fall and/or winter periods (57, 26 and 29mm, respectively, during the three years) contributed probably to leaching soluble salts from the root zone. Highest carrot yields for the three years were obtained with SWB scheduling technique FI-100, (29.5, 28.7 and 26.8t/ha) although we didn’t find significant differences with the regulated deficit irrigation regime (FI-DI60). Compared to FI-100, significant reductions in carrot yields were observed under DI-80 and DI-60 deficit irrigation treatments resulting from a reduction in roots number/m2 and average root weight. The farmer’s method not only caused significant reductions in yield but also resulted in using 43–57% more water and increased soil salinity. For all irrigation treatments, carrot yields were higher in the first year compared to the two following years. Water productivity (WP) values reflected this difference and varied between 3.2 and 9.7kg/m3. The lowest WP values were observed for the farmer’s method, while the highest values were obtained under DI-60 deficit irrigation treatment. The scheduling technique using SWB with variable doses is more efficient than the traditional technique used by farmers in carrot production. The FI-100 irrigation scheduling seems to optimize the use of saline water in carrot production and to control soil salinity. Under situations of water shortage, adopting deficit irrigation strategies (FI-DI60 and DI-80) could be an alternative for irrigation scheduling of carrot crop under the conditions of Mediterranean arid in southern Tunisia. [Copyright &y& Elsevier]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Many communities in South Africa struggle to access reliable and adequate quantities of potable water for diverse water requirements. This is against the backdrop of decreasing freshwater availability and increasing water demands. Currently, interest in the reuse of wastewater for non-drinking water requirements is increasing. This paper therefore provides an overview of the South African water resources situation and wastewater 1 [1] Wastewater refers to domestic, institutional, and industrial liquid waste products collected through networks of pipes (sewers) into treatment plant. generation in order to put the need for wastewater reuse into perspective. Potential for broader implementation and parameters influencing wastewater reuse based on local attitudes and experience were discussed with recommendations to facilitate broader implementation of wastewater reuse. This paper concludes that significant potential exists for implementing wastewater reuse for large non-drinking applications (e.g. landscape irrigation and industrial processes) in arid areas of South Africa especially Western Cape Province. Parameters highlighted from local attitudes and experience to influence broader implementation in addition to aridity include distance from source, retrofitting versus new installations, quantity of reuse, tariffs, source quality, public health, willingness, public trust and knowledge, and regulations and guidelines for reuse. Prior to implementation, it is recommended that these parameters be addressed. [ABSTRACT FROM AUTHOR]

The article presents a study regarding the determination of anthropogenic nitrogen (N) deposition which increases the risk of fire at the deserts in Southern California. The DayCent model was utilized for the study to assess the precipitation, soil texture and availability of N. The study demonstrated the importance of considering precipitation and N deposition when evaluating fire risk in arid landscapes.

The article presents the study that evaluates the soil carbon (C) accumulation under and around pinyon-juniper canopies in southern Utah woodlands following woody expansion. It notes that it measures C and nitrogen (N) stocks and has utilized simple non-steady-state modeling approach to assess the soil C accumulation. Moreover, it determines the distribution of soil organic matter (SOM) through soil physical fractions.

Abstract: Little is known about the contribution of arid and semiarid regions to the carbon balance at a global scale. The lack of information is especially noticeable for the Gran Chaco, which covers an area of about 1,200,000km2 in South America. This study quantified carbon pools and their changes along a land-use gradient in the Dry Chaco, the driest portion of the Gran Chaco, measured in the aboveground biomass and in soils (20cm depth). The work was conducted in the Chancaní reserve, where the best preserved forests of the region are found, and in surrounding areas, including a primary forest, a secondary forest and shrubby grasslands. Previous works indicate that the entire area was originally covered by forests similar to those found at the Chancaní reserve, and that the land-use changes occurred at least 30 years prior to this study. Total aboveground carbon stock, which comprises the total amount of living organic matter in trees and shrubs, was 30.31MgCha−1 in the primary forest, which was reduced to 8.38MgCha−1 in the secondary forest and to 1.37MgCha−1 in shrubby grasslands. Carbon stock in the tree component decreased drastically between the primary and the secondary forests from 25.40 to 5.11MgCha−1. The component described as saplings of trees and shrubs also decreased significantly among the three communities from 4.91MgCha−1 in the primary forest to 3.27MgCha−1 in the secondary forest and to only 1.37MgCha−1 in the shrubby grasslands. No significant differences were detected in the carbon content per unit area of soil, although it decreased from 34.59MgCha−1 in the primary forest to 28.04MgCha−1 in the secondary forest and to 22.93MgCha−1 in the shrubby grassland, with a significant increase in soil bulk density in the disturbed communities. Therefore, differences in carbon stocks between communities were primarily the result of differences in vegetation biomass, whereas changes in the land-use gradient analyzed had a lower impact on soils. Nevertheless, soil constitutes the largest pool, and more severe ecological disturbances could lead to important changes in net carbon storage. [Copyright &y& Elsevier]

The article presents a study on the multi-decadal effects of soil grazing in biogeochemical and physical properties in Southeast Utah. It highlights the comparison of non-grazed grasslands in Canyonlands National Park along with their geomorphic, geochemical and geologic features. It also outlines the issue of soil erosion as well as impact of carbon and nitrogen on the land.

• Silt deposition ranged from 54 g m−2 yr−1 (inner) to 207.4 g m−2 yr−1 in the corner. • Clay flux was in inner (124.4 g m−2 yr−1) and corner (123.4 g m−2 yr−1) locations. • The total deposition (silt+clay) was maximal (330.8) and minimal (155.6 g m−2 yr−1). • Palygorskite, smectite, and vermiculite were the most deposited clay in all regions. • Stabilized dunes do not disturb dust and play an important role in air purification. Sand dune hills were stabilized by petroleum mulch and biological methods in southwest Iran. The present study aims to identify the effects of these landscapes on airborne dust entrapment in five regions, including uphill (UH), downhill (DH), and canopy tree positions after 54 years. These locations were at different distances from dust sources and prevailing winds. The results revealed that salinity in the study areas showed the following trend: canopy > UH > DH. Silt particles were entrapped in the corner 4 times greater than the inner areas. Moreover, silt deposition flux ranged from 54 gm−2 yr−1 (the minimum) in the inner site (Al-Baji) to 207.4 g m−2 yr−1 (the maximum) in the corner site (SG). Unlike silt, clay flux was maximal in both inner (124.4) and corner (123.4) locations due to the movement of fine materials in high elevations. The total deposition of materials (silt + clay) was maximal (330.8) and minimal (155.6 g m−2 yr−1) in the corner and inner sites, respectively. The clay mineralogy indicated that these hills had two groups of minerals. Primary minerals, i.e. carbonates and silicates, were inherited from parent materials. Secondary minerals were identified in surface soil, and peaks in the subsurface were very weak. Wind sediments added these clays to the surfaces. The abundance of these clays showed the following trend: palygorskite > smectite > vermiculite. It was found that these areas do not disturb the atmosphere by dust and play an important role in air purification because the surface roughness of these hills was promoted by artificially planted trees. [ABSTRACT FROM AUTHOR]

Yearly net carbon sequestration of Eucalyptus microtheca under three water-energy regimes in Abu Dhabi (MSF: multi-stage flash desalination; RO-Grid: grid-powered reverse-osmosis desalination; RO-Solar: solar photovoltaic powered reverse-osmosis desalination). • Trees watered from multi-stage flash desalination have negative net carbon storage. • Trees watered from solar-powered RO-desalination have positive net carbon storage. • The highest negative storage species now may have high positive storage in future. • Neighborhood tree planting can offset renewable supplied household energy demand. This paper explores the future of landscapes in arid, coastal regions based on 4 water-energy regimes, using a case study of villa neighborhoods in Abu Dhabi, United Arab Emirates. It examines the potential for the planting of 15 selected tree species for carbon storage under various water-energy regimes to create carbon neutral (or negative) villa neighborhoods. Recent improvements to solar photovoltaic and reverse-osmosis desalination technology have lowered the carbon emissions for water production by over 99% relative to current gas-powered multi-stage flash desalination (0.08 kg CO 2 /m3 vs.12.8 kg CO 2 /m3). This allows trees planted in hot, desert climates to utilize treated ocean water while net sequestering between 1.7 and 38.2 kg C/tree/yr depending on species. When planted in existing neighborhood open spaces, we find that net carbon storage rates from trees are significant (15–800%) relative to operational emissions rates for building energy (cooling, lighting, equipment) when households are supplied from 100% renewable energy sources. Thus, as technology advances, landscape design strategies in the region could evolve to maximize planting to sequester carbon while also creating more comfortable outdoor spaces that enhance the livability of neighborhoods. This study provides a first step in identifying the potential for landscape architectural design to employ a tree-based, neighborhood scale, carbon storage strategy in arid regions such as those in the Arabian Peninsula. As nations move towards a carbon-neutral future, it is imperative to develop innovative solutions that address urban sustainability, especially in resource-challenged and extreme climate regions where new urban development is planned. [ABSTRACT FROM AUTHOR]