Abstract:Most recent studies relating to the classification of vegetation species on the individual level use cutting-edge sensors and follow a data-driven approach, aimed at maximizing classification accuracy within a relatively small allocated area of optimal conditions. However, this approach does not incorporate cost-benefit considerations or the ability of applying the chosen methodology for applied mapping over larger areas with higher natural heterogeneity. In this study, we present a phenology-based cost-effective approach for optimizing the number and timing of unmanned aerial vehicle (UAV) imagery acquisition, based on a priori near-surface observations. A ground-placed camera was used in order to generate annual time series of nine spectral indices and three color conversions (red, green and blue to hue, saturation and value) in four different East Mediterranean sites that represent different environmental conditions. After outliers' removal, the time series dataset represented 1852 individuals of 12 common vegetation species and annual herbaceous patches. A feature selection process was used for identifying the optimal dates for species classification in every site. The feature selection can be designed for various objectives, e.g., optimization of overall classification, discrimination between two species, or discrimination of one species from all others. In order to evaluate the a priori findings, a UAV was flown for acquiring five overhead multiband orthomosaics (five bands in the visible-near infrared range based on the five optimal dates identified in the feature selection of the near-surface time series of the previous year. An object-based classification methodology was used for the discrimination of 976 individuals of nine species and annual herbaceous patches in the UAV imagery, and resulted in an average overall accuracy of 85% and an average Kappa coefficient of 0.82. This cost-effective approach has high potential for detailed vegetation mapping, regarding the accessibility of UAV-produced time series, compared to hyper-spectral imagery with high spatial resolution which is more expensive and involves great difficulties in implementation over large areas.

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Genetic studies on core versus peripheral populations have yielded many patterns. This diversity in genetic patterns may reflect diversity in the meaning of "peripheral populations" as defined by geography, gene flow patterns, historical effects, and ecological conditions. Populations at the lower latitude periphery of a species' range are of particular concern because they may be at increased risk for extinction due to global climate change. In this work we aim to understand the impact of landscape and ecological factors on different geographical types of peripheral populations with respect to levels of genetic diversity and patterns of local population differentiation. We examined three geographical types of peripheral populations of the endangered salamander, Salamandra infraimmaculata, in Northern Israel, in the southernmost periphery of the genus Salamandra, by analyzing the variability in 15 microsatellite loci from 32 sites. Our results showed that: 1) genetic diversity decreases towards the geographical periphery of the species' range; 2) genetic diversity in geographically disjunct peripheral areas is low compared to the core or peripheral populations that are contiguous to the core and most likely affected by a founder effect; 3) ecologically marginal conditions enhance population subdivision. The patterns we found lead to the conclusion that genetic diversity is influenced by a combination of geographical, historical, and ecological factors. These complex patterns should be addressed when prioritizing areas for conservation.

The Endangered mountain gazelle Gazella gazella was once widespread throughout the Levant. Over the past 100 years its population fluctuated greatly as a result of various anthropogenic threats and disturbances. We review the dynamics of the mountain gazelle throughout this period in Israel, its last remaining stronghold, with c. 5,000 individuals. During the 20th century Israel's human population increased steadily at an annual rate of 2%; the population density is currently 430 persons per km2 and is forecast to increase further. This presents an array of threats to the mountain gazelle, including habitat change, fragmentation and isolation by roads, railways and fences, poaching, road kills and predation by increasing populations of natural predators and feral dogs, sustained partly by anthropogenic food waste. These threats may act in synergy to amplify their effects. We present an overview of how these factors acted in the past and are currently threatening the survival of this species. We also review the policy and management actions, both implemented and still required, to ensure the persistence of the mountain gazelle. In addition, we analyse connectivity in the landscape, highlighting highly fragmented gazelle populations, and suggest potential interventions. The mountain gazelle exemplifies an ungulate with both great vulnerability to human pressures and a large breeding potential. As more regions, in Israel and elsewhere, are converted to human dominated landscapes, pressures on wildlife are increasing, and lessons from the mountain gazelle could prove valuable.

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The geographic location of Israel and the Palestinian Authorityon the border between Mediterranean and desert climate, and the strong topographic and geomorphological variation resulting from its position on the Great African Rift Valley, combine to sustain a great diversity of landscapes in a very small country. The purpose of this study is to determine whether the protected areas in Israel and the Palestinian Authority adequately represent the range of landscapes and ecosystems in the region. Altogether, we defined 23 natural ecosystem-units in Israel and the Palestinian Authority, of which 17 are terrestrial landscapes and 6 are aquatic systems. In considering the adequacy of coverage in protected areas, we mapped Israel and the Palestinian Authority landscapes according to a set of environmental factors (climatic, geomorphological, geological and botanical) that we believe most effectively distinguish landscape types in this region. When the separation between adjacent units relies on sharp topographic or edaphic change in the landscape, the mapped units can be separated by a clear and sharp line. When adjacent units are actually a gradient of continuous environmental conditions the separation lines relied mostly on botanic characteristics. The main land use categories in this analysis were urban areas, agricultural areas, nature reserves, national parks and forest reserves. For the first time in Israel and the Palestinian Authority, we quantified the different landscape types under the different categories of land use. This process, known as systematic conservation planning, allowed us to detect natural landscapes that are underrepresented in protected areas, and can guide decision makers to establish or improve management for the better representation of biodiversity.

Over the years, Israel's centralized national planning framework and the intense competition on the limited available land played a crucial factor in designing the spatial distribution of the protected areas in Israel. When examining the spatial properties of the protected areas, it was found that they do not adequately represent the variety of the ecosystems in Israel. According to the systematic conservation planning approach, we aimed to examine how optimization algorithms (e.g., MARXAN) would inform us on high priority areas for conservation. We created proxies for anthropogenic disturbance, and for the susceptibility of designating new protected areas subject to existing national and regional land use master plans. Our conservation targets were defined on the basis of the spatial distribution of 461 endangered vertebrate and plant species (red species), as well as by defining and mapping 21 main ecosystems. The results highlight the limited options of significantly improving the representativeness provided by the existing protected areas, due to the diminishing availability of open areas, which may be available to be designated as protected areas. However, the results also emphasize the conservation potential of agricultural land, as well as the need for preserving small and fragmented rare habitats.

The biodiversity of native species is diminishing in many regions as natural habitats are being replaced by human settlements and agriculture. Top predators, such as large raptors, are especially sensitive to habitat change, and they present flagship species due to the interest in them by the public. By protecting the raptors’ habitats we also protect other species that reside within these habitats. A large population of Short-toed Eagles (Circaetus gallicus, hereafter StE) were studied in the Judea region of Israel across a 1,175 km2 study site during the 2006–2008 breeding seasons, in order to determine whether the different types of habitat affect the number of successful breeding pairs. During the three-year study, we recorded 288 breeding attempts by StE pairs in 156 different nests located mainly on trees. Of the successful StE pairs, 76.9% bred in natural habitats while fewer pairs than expected bred in agricultural areas and human settlements. The mean number of successful StE pairs was positively related to the proportion of natural habitat types and negatively related to the proportion of human settlements and agriculture. Compared to successful pairs breeding in grids with a low density of StE, grids with higher breeding densities of successful pairs comprised more natural habitat types and less agricultural land and human settlement. Even though the population of StE in Israel is large, its future may be at risk as natural habitats are increasingly being destroyed and replaced by human settlements and agriculture. Conservation programs are therefore needed in order to protect as much natural habitat types as possible prior to urban planning and realisation.