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Geodiversity integrates physical parameters such as geological, geomorphological, and pedological components. It represents the abiotic diversity of the earth surface layer. It incorporates geological (bedrocks and mineral sediments), geomorphological (geography, land surface formations, physical processes), pedological (soils), and hydrological characteristics. Biological soil crusts (biocrusts) play an essential role in regulating the biogeochemical cycles of carbon and nitrogen. Their ability is dependent on habitat conditions, composition, and cover percentage of the ground surface, all of which are affected by geodiversity. This study’s objective was to assess the effects of geodiversity on the biogeochemical functions of biocrusts by regulating the soil water dynamics and the subsequent impact on readily available nitrogen and carbon. Hillslope geodiversity is determined by the geodiversity found in the stone cover on the ground surface and in the stone content throughout the soil profile, as well as by the soil profile thickness of the underlying bedrock. We hypothesized that in dry environments, the physical conditions in high-geodiversity hillslopes, compared to low-geodiversity hillslopes, positively affect the soil water budget, which would affect the biocrusts and their readily available nitrogen and carbon. The results showed higher soil moisture content in the heterogeneous hillslopes. The ammonium and labile organic carbon in the biocrusts were more substantial in the heterogeneous than in the homogeneous hillslopes, while soil protein, nitrite, and soil organic matter were similar. We suggest that the comparatively high soil moisture content in the heterogeneous hillslopes stimulates biocrust community activities and increases the readily available nitrogen and carbon, thus improving the survival of shrubs in these ecosystems under long-term drought conditions. [ABSTRACT FROM AUTHOR]

The agricultural landscape constitutes a mosaic of various crop plots intertwined with non-disturbed natural areas. Extensive use of pesticide spraying can pollute the natural areas, causing damage to the natural food webs. The damages to the natural systems can be temporary and cumulative. Although many studies have dealt with the results of pesticide spraying drift to the natural environment, we lack knowledge on the role of dust particle transfer of pesticides. The study aims to investigate the dust particles as pesticide carriers. It examines the presence and accumulation of pesticides in vegetation and soils of the farmlands and natural areas nearby in two different climatic zones, Mediterranean and semiarid. It was hypothesized that seasonal agricultural activities affect the transport of dust particles with pesticides. The research methods included qualitative and quantitative analyses of pesticides in a hierarchy of distances from agriculture fields into natural and nearby. The renewal of the results indicated that seasonal agricultural activity leading to the transport of dust particles was a major contribution to the spatial distribution of pesticides, in both climate zones. Here we reveal results that must be an essential principle in the use of pesticides in agricultural fields, especially in nearby uninhabited areas. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the function of tree belts in reducing the aeolian transport of dust particles carrying pesticides. The study examined the importance of the buffer zones created by commonly planted trees (Eucalyptus camaldulensis, Pinus halepensis (pine) and Ceratonia siliqua (carob)). The methods include analyzing the quantity and the chemical composition of pesticides carried by aeolian dust particles from the intensively cultivated fields and orchards, where pesticides were applied, towards the tree belts nearby. Eighteen different chemicals used as insecticides, fungicides and herbicides, were found both in the agricultural fields and in the adjacent tree belts, suggesting an important function of the trees. This ecological service has rarely been taken into consideration by management policies of tree plantings in farmland areas. To integrate this service into agriculture, especially in the case of agricultural fields and orchards, which are adjacent to populated areas, planting tree belts should be positively considered as a means for reducing aeolian dust and air pollution, mainly in order to reduce leakage of pesticides, which are a cause for significant health concerns. [ABSTRACT FROM AUTHOR]

Soil quality (SQ) assessment has numerous applications for managing sustainable soil function. Airborne imaging spectroscopy (IS) is an advanced tool for studying natural and artificial materials, in general, and soil properties, in particular. The primary goal of this research was to prove and demonstrate the ability of IS to evaluate soil properties and quality across anthropogenically induced land-use changes. This aim was fulfilled by developing and implementing a spectral soil quality index (SSQI) using IS obtained by a laboratory and field spectrometer (point scale) as well as by airborne hyperspectral imaging (local scale), in two experimental sites located in Israel and Germany. In this regard, 13 soil physical, biological, and chemical properties and their derived soil quality index (SQI) were measured. Several mathematical/statistical procedures, consisting of a series of operations, including a principal component analysis (PCA), a partial least squares-regression (PLS-R), and a partial least squares-discriminate analysis (PLS-DA), were used. Correlations between the laboratory spectral values and the calculated SQI coefficient of determination (R2) and ratio of performance to deviation (RPD) were R2 = 0.84; RPD = 2.43 and R2 = 0.78; RPD = 2.10 in the Israeli and the German study sites, respectively. The PLS-DA model that was used to develop the SSQI showed high classification accuracy in both sites (from laboratory, field, and imaging spectroscopy). The correlations between the SSQI and the SQI were R2 = 0.71 and R2 = 0.7, in the Israeli and the German study sites, respectively. It is concluded that soil quality can be effectively monitored using the spectral-spatial information provided by the IS technology. IS-based classification of soils can provide the basis for a spatially explicit and quantitative approach for monitoring SQ and function at a local scale. [ABSTRACT FROM AUTHOR]

The main objective of the present study was to apply a slope-based spectral method to both dry and fresh pasture vegetation. Differences in eight spectral ranges were identified across the near infrared-shortwave infrared (NIR-SWIR) that were indicative of changes in chemical properties. Slopes across these ranges were calculated and a partial least squares (PLS) analytical model was constructed for the slopes vs. crude protein (CP) and neutral detergent fiber (NDF) contents. Different datasets with different numbers of fresh/dry samples were constructed to predict CP and NDF contents. When using a mixed-sample dataset with dry-to-fresh ratios of 85%:15% and 75%:25%, the correlations of CP (R2 = 0.95, in both) and NDF (R2 = 0.84 and 0.82, respectively) were almost as high as when using only dry samples (0.97 and 0.85, respectively). Furthermore, satisfactory correlations were obtained with a dry-to-fresh ratio of 50%:50% for CP (R2 = 0.92). The results of our study are especially encouraging because CP and NDF contents could be predicted even though some of the selected spectral regions were directly affected by atmospheric water vapor or water in the plants. [ABSTRACT FROM AUTHOR]

In this study, we develop a spectral method for assessment of pasture quality based only on the spectral information obtained with a small number of wavelengths. First, differences in spectral behavior were identified across the near infrared-shortwave infrared spectral range that were indicative of changes in chemical properties. Then, slopes across different spectral ranges were calculated and correlated with the changes in crude protein (CP), neutral detergent fiber (NDF) and metabolic energy concentration (MEC). Finally, partial least squares (PLS) regression analysis was applied to identify the optimal spectral ranges for accurate assessment of CP, NDF and MEC. Six spectral domains and a set of slope criteria for real-time evaluation of pasture quality were suggested. The evaluation of three level categories (low, medium, high) for these three parameters showed a success rate of: 73%-96% for CP, 72%-87% for NDF and 60%-85% for MEC. Moreover, only one spectral range, 1748-1764 nm, was needed to provide a good estimation of CP, NDF and MEC. Importantly, five of the six selected spectral regions were not affected by water absorbance. With some modifications, this rationale can be applied to further analyses of pasture quality from airborne sensors. [ABSTRACT FROM AUTHOR]

Drought events cause changes in ecosystem function and structure by reducing the shrub abundance and expanding the biological soil crusts (biocrusts). This change increases the leakage of nutrient resources and water into the river streams in semi-arid areas. A common management solution for decreasing this loss of resources is to create a runoff-harvesting system (RHS). The objective of the current research is to apply geo-information techniques, including remote sensing and geographic information systems (GIS), on the watershed scale, to monitor and analyze the spatial and temporal changes in response to drought of two source-sink systems, the natural shrubland and the human-made RHSs in the semi-arid area of the northern Negev Desert, Israel. This was done by evaluating the changes in soil, vegetation and landscape cover. The spatial changes were evaluated by three spectral indices: Normalized Difference Vegetation Index (NDVI), Crust Index (CI) and landscape classification change between 2003 and 2010. In addition, we examined the effects of environmental factors on NDVI, CI and their clustering after successive drought years. The results show that vegetation cover indicates a negative ?NDVI change due to a reduction in the abundance of woody vegetation. On the other hand, the soil cover change data indicate a positive ?CI change due to the expansion of the biocrusts. These two trends are evidence for degradation processes in terms of resource conservation and bio-production. A considerable part of the changed area (39%) represents transitions between redistribution processes of resources, such as water, sediments, nutrients and seeds, on the watershed scale. In the pre-drought period, resource redistribution mainly occurred on the slope scale, while in the post-drought period, resource redistribution occurred on the whole watershed scale. However, the RHS management is effective in reducing leakage, since these systems are located on the slopes where the magnitude of runoff pulses is low. [ABSTRACT FROM AUTHOR]

Effective grazing management in Australia's semi-arid rangelands requires monitoring landscape conditions and identifying sustainable and productive practice through understanding the interactions of environmental factors and management of soil health. Challenges include extreme rainfall variability, intensifying drought, and inherently nutrient-poor soils. We investigated the impacts of grazing strategies on landscape function—specifically soil health—as the foundation for productive pastures, integrating the heterogenous nature of grass tussocks and the interspaces that naturally exist in between them. At Wambiana—a long-term research site in north-eastern Australia—we studied two soil types, two stocking rates (high, moderate), and resting land from grazing during wet seasons (rotational spelling). Rotational spelling had the highest biocrust (living soil cover), in interspaces and under grass tussocks. Biocrusts were dominated by cyanobacteria that binds soil particles, reduces erosion, sequesters carbon, fixes nitrogen, and improves soil fertility. Rotational spelling with a moderate stocking rate emerged as best practice at these sites, with adjustment of stocking rates in line with rainfall and soil type recommended. In drought-prone environments, monitoring the presence and integrity of biocrusts connects landscape function and soil health. Biocrusts that protect and enrich the soil will support long-term ecosystem integrity and economic profitability of cattle production in rangelands. [ABSTRACT FROM AUTHOR]

The 'wadis' (ephemeral incised channels in arid regions) concern badlands with low agriculture utilisation that expands to neighbouring cultivated areas. They are noticeable and unique landforms characterised by vegetation patches and seasonal flood flows with scenic beauty that must be conserved. The wadi characteristics have influenced the way of life of their indigenous residents from ancient times until now. The main one is grazing with small ruminants (SR). The authorities and public consider grazing in these areas as a destructive land management practice that should be reduced. To assess the viability of grazing in such regions, we hypothesised that fluvial and biological flows tightly correlate with the wadis' landforms, channels and slopes. The site of study is located in the Yeroham mountains nearby the Rahma planned Bedouin village. Five different transects of channels and slopes were located over representative wadis, including those exposed to grazing. The finding indicates that a herbaceous vegetation expansion uphill was observed only in grazed transects, while the wadi slope patterns affect its patterns. It contains an increased soil water content (from a similar value of 5% until 13% change in the grazed transect), 1.5% higher soil organic matter, 0.08 mg Kg−1 higher Nitrite content and 1–2% higher clay content in the grazed transects, up to 4 m ahead from the channel. The novelty of this finding suggested that the SR influences the organic matter to reach the wadi channel and facilitate the adherence of aggregated clay and the formed colluvial layer that serves as a substrate to the expanded vegetation growth. Adequate implementation of these grazing patterns may rehabilitate degraded 'wadis' and increase their tourism eligibility. [ABSTRACT FROM AUTHOR]

The aim of the study was to identify the trends and dynamics of changes in the chemical and biochemical properties of soil induced by rotational grazing of farmed deer. Soils pH and the content of mineral nitrogen forms, total nitrogen, and organic carbon were determined in the study and the activity of three soil enzymes. The monitored soils were slightly acidic and neutral, with pH in 1 mol KCldm−3 ranging from 6.37 to 7.03. The contents of content of organic carbon, total nitrogen in the monitored soils were in the range of 9.42–19.37 gkg−1 and 1.13–2.24 gkg−1, respectively, while the contents of N-NH4+ and N-NO3− of 1.34–7.08 mgkg−1 and 102.8–619.5 mgkg−1, respectively. The mean levels of nitrate nitrogen in the pasture soils were lower than that in the mown soil. The soils from the pastures were characterized by a higher level of available phosphorus, potassium, and magnesium forms than the mown soil. In the deer grazing areas, the activity of all enzymes was clearly higher than in the soil from the control plot. The results of the present pilot study have demonstrated a positive effect of cervid grazing on the biochemical parameters of the soil environment. [ABSTRACT FROM AUTHOR]

Traditional sheep and cattle grazing in natural semiarid Mediterranean, Asian and African regions is based on night corrals, where animal secretions accumulate. Lack of management and disregard for the long-term effects of using the same sites for corrals on underground soil characters may negatively affect soil values. This locally increases the content of organic matter and nutrients such as nitrogen, potassium, phosphorus and others that are stockpiled in the corrals. As these activities are long-lasting, they affect the soil parameters, leading to nutrient leakage and contamination of the upper and sub-soil surface. This alarming situation demands a technique to reveal and estimate sub-soil contamination in corrals by using the frequency domain electromagnetic method (FDEM) for measuring soil salinity. The aim of this study is to correlate electrical conductivity measurement with the FDEM to study the influence of sheep corrals on the changes within the sub-soils of corrals in the semiarid region of the northern Negev desert. The results show that a correlation was found between the laboratory soil analysis and the electromagnetic analysis in all sites. Plugot forest site results found to be anomalous indicated sub-surface conductivity resulting from the presence of the corral, with a higher conductivity value of about 230 mS/m, while no differences were found between the soil layers outside the active corral and the corral edge. High values were found in the center of the active corral: 960 mS/m by the laboratory analysis and 200 mS/m by the FDEM. The values obtained in the abandoned corral in the laboratory were about 10 times lower than those obtained from the active corral and six times lower that those found with the FDEM. At the Beit Nir site, high values were found in the center of the active corral: 300 mS/m by the laboratory analysis and 130 mS/m by the FDEM. With different sources of manure, cattle and sheep have shown similar patterns of electrical conductivity (EC) obtained in the sub-soil layers between active and abandoned corrals: high in the center and low at the edge and outside the corral and decreased with depth. [ABSTRACT FROM AUTHOR]

Frequent, region-wide monitoring of changes in pasture quality due to human disturbances or climatic conditions is impossible by field measurements or traditional ecological surveying methods. Remote sensing imagery offers distinctive advantages for monitoring spatial and temporal patterns. The chemical parameters that are widely used as indicators of ecological quality are crude protein (CP) content and neutral detergent fiber (NDF) content. In this study, we investigated the relationship between CP, NDF, and reflectance in the visible–near-infrared–shortwave infrared (VIS–NIR–SWIR) spectral range, using field, laboratory measurements, and satellite imagery (Sentinel-2). Statistical models were developed using different calibration and validation data sample sets: (1) a mix of laboratory and field measurements (e.g., fresh and dry vegetation) and (2) random selection. In addition, we used three vegetation indices (Normalized Difference Vegetative Index (NDVI), Soil-adjusted Vegetation Index (SAVI) and Wide Dynamic Range Vegetation Index (WDRVI)) as proxies to CP and NDF estimation. The best models found for predicting CP and NDF contents were based on reflectance measurements (R2 = 0.71, RMSEP = 2.1% for CP; and R2 = 0.78, RMSEP = 5.5% for NDF). These models contained fresh and dry vegetation samples in calibration and validation data sets. Random sample selection in a model generated similar accuracy estimations. Our results also indicate that vegetation indices provide poor accuracy. Eight Sentinel-2 images (December 2015–April 2017) were examined in order to better understand the variability of vegetation quality over spatial and temporal scales. The spatial and temporal patterns of CP and NDF contents exhibit strong seasonal dependence, influenced by climatological (precipitation) and topographical (northern vs. southern hillslopes) conditions. The total CP/NDF content increases/decrease (respectively) from December to March, when the concentrations reach their maximum/minimum values, followed by a decline/incline that begins in April, reaching minimum values in July. [ABSTRACT FROM AUTHOR]