Har Negev

Har Negev Reserve (HNR) is a part of the central Negev Highlands, and has an annual rainfall of 80-100 mm, about 200 nights of dew and a mean annual temperature of 17°-19°C. HNR is characterized by high degree of geo-diversity induced by geological and geomorphological long term processes. Vegetation is mostly in a diffused spot pattern on the slopes and at higher cover in riverbeds. HNR cover an area of about 1700 km² that is colonized by 500 documented species of plants and an additional of 150 undocumented species are estimated to live in the area.

In relation to fauna in HNR there are 21 species of land snails, 41 species of reptiles, 55 species of mammals, 201 species of nesting birds and 30 species of butterflies (species distribution was estimated by BioClim modelling extrapolation within the BioGIS web site). It is one of the 15 IPAs (Important Plant Areas) within Israel. The reserve incorporates several endemic species of plants such as Amygdalus ramonensis, Origanum ramonense, Bufonia ramonensis, Euphorbia ramonensis, Capparis ramonensis, Rheum palaestinum, Iris regis-uzziae. Within the central Negev Highlands there are approximately 32 species of plants that are considered within the red list of endangered species of Israel. One of the remarkable features of this habitat is the occurrence of large Pistacia atlantica trees at high elevations. Additional trees can be found such as: Rhamnus dispermus, Rhus tripartite and Ceratonia siliqua. Three large herbivores can be found within the reserve. Gazella dorcas and two reintroduced species the Equus hemionus and Oryx leucoryx. Bats are an important part of the ecological system of the Negev Highlands, species such as the Otonycteris hemprichii which is known to be an important predator of scorpions and beetles. Predators are still common within this region and include: Panthera pardus, Canis lupus, Vulpes rueppelli, Vulpes vulpes, Vulpes cana, Felis silvestris, Caracal caracal, Hyaena hyaena and Meles meles.

Due to the desert climate, water is an important limiting factor in the distribution of species in time and space in the region. There are very few natural springs within the reserve and most water comes from ancient waterholes and more recent waterholes maintained by the local Bedouin population. Such natural springs and waterholes are the cause of great conflict between human recreation and the need of animals for water.

Currently there are a few hundred Bedouins living in several small settlements very close to the reserve and a significant part of their grazing is done within the reserve. There is very little information regarding the impact of grazing on the vegetation within such a hyper-arid environment.

With the introduction of modern agriculture into the vicinity of the reserve, there is a growing conflict between wildlife and farmers. A conflict that is predicted to grow in the coming years, yet we know very little about the impact of human settlement and agriculture on the wildlife in the hyper dry region.

Because of the harsh environment there are very few invasive species that currently threaten the reserve. The main invasive plant species is Nicotiana glauca which is found mainly in the wadi's. Currently invasive animal species restrict themselves close to settlements or military bases, such as Acridotheres tristis and Canis simensis.

Main threats on the natural habitat sorted by its potential damage to the reserve: Human settlement and infrastructure, agriculture, military activities, mining in quarry, tourism, climate change, overgrazing and hunting. The UNESCO Heritage Site, namely the Incense Route and the ancient Natatean town of Avdat, along with the associated fortresses and agricultural landscapes are located within the HNR.  Together they reflect the hugely profitable trade in frankincense and myrrh from south Arabia to the Mediterranean, which flourished from the 3rd century BC until the 2nd century AD.  With the vestiges of their sophisticated irrigation systems, urban constructions, forts and caravanserai, they bear witness to the way in which the harsh desert was settled for trade and agriculture.

HNR represents a hydro-geo-ecological protected system functioning under extreme environmental conditions related to temperature and water stresses. HNR is characterized by wide range of unique biodiversity, in terms of number of taxa, endemicity and functional diversity that is able to cope and form functioning ecosystems under extreme environmental envelope. HNR demonstrates distinctive pathways of ecosystem functioning that combine ecohydrologicl and geoecological processes that produce specific cultural and habitat ecosystem services related to the functional links between geodiversity and biodiversity.

The geological development of the Negev highlands has given rise to a remarkable link between geodiversity and biodiversity via hydrological processes that result in a landscape mosaic rich in habitats. Therefore, HNR is the cornerstone of geo and bio conservation in Israel that is essential in providing:

- the knowledge base for understanding of natural processes of life supporting systems under water limitation.  

- the physical and biological basis for landscape and scenery formation that has a profound influence on habitats, wildlife and human in arid zones.

- the resources for tourism-based activities in a geo-ecological context;

- a powerful influence on cultural heritage as a source of inspiration for art, sculpture, music, poetry, literature and education

- the resources for a variety of recreation and outdoor activities, with consequent benefits for people’s well-being.

HNR studies as a mean for understanding the function, ecosystem services and management of a protected area adopted a holistic approach recognizing that landscape formed by geo-hydro ecological processes links organisms, people and their cultures through the interactions of geodiversity and biodiversity. HNR studies are focused on selected key species and habitats with emphasis on the underlying physical processes that are essential to the maintenance of biodiversity and its function. HNR demonstrates a significant relationship between ecosystem structures and functions specified in the biophysical domain and human needs specified in the social domain.

Biodiversity, functions and services provided by HNR are in danger, because they are fragile ecosystems, highly vulnerable to current impacts arising from climate changes associated with higher frequency and magnitude of drought and flood events and land use changes related to settling the desert and increase in ecoturism. HNR is considered inherently vulnerable because of its narrow environmental envelopes and the fact that it appears to be near climatic thresholds for life. Ecosystems near their limits of environmental tolerance are vulnerable because under more extreme conditions the organisms and their organization into functional ecosystems will face novel environmental conditions that it will be very difficult to adapt to.

Intensive research, monitoring and modelling programs dealing with the status and trends of hydro- geo- eco systems in the Negev produced a large amount of data that can be integrated into a unified data base in order to analyze and modelling ecosystem processes trends and services in HNR.

In-situ information are produced mainly by scientific studies in two LTER sites (Avdat and Ramon) and two Long term associated sites (Halukim and Zin).

Avdat (established 1958, LTER site from 1995) - Data available on: biodiversity of plants, animals and microbs, food webs, meteorology, watershed ecology, decomposition, pedology, plant-water relationships, runoff farming and cultural diversity.

Ramon  (established 1985, LTER site from 1998) - Data available on: biodiversity of plants, animals, population dynamics of animals, primary production, meteorology, hydrology, geology, geomorphology.

Halukim site (established 1970) - Data available on: biodiversity of plants, animals, population dynamics of plants and animals, hydrology,geology, geomorphology, watershed ecology and soil erosion.

Zin site (established 1972) - Data available on: biodiversity of plants, animals, population dynamics of animals,  food web, energy flow and meteorology.

HNR has been observed periodically by several space systems such as Landsat (since 1982), NOAA-AVHRR and MODIS (since July 1981), and SeaWiFS (1997-2010).  In addition, BGU has a huge database of multi and hyperspectral images acquired by a large variety of airborne and space borne sensors.  When VENµS will be launched in early 2016, HNR will be observed by this system as well.

A platform of spatially explicit mathematical models for water-limited plant communities has been developed. The models capture basic biomass-water feedbacks that account for self-organized vegetation patchiness, and provide means for studying the relationships between the abiotic environment, functional diversity and ecosystem function in spatially extended ecosystems. The platform has been used to study and gain insight into a variety of problems in spatial ecology, including:

1. Vegetation patterns along environmental gradients: periodic regular patterns (spots, stripes, gaps), irregular patterns in multi-stability ranges, scale-free patterns under conditions of global competition.
2. Vegetation patchiness in heterogeneous environments: the interplay between self-organized patchiness and patchiness dictated by a physical template, such as in rock-soil mosaics.
3. Plants as ecosystem engineers: transitions from competition to facilitation as water stress increases in woody-herbaceous plant communities.
4. Desertification: gradual and abrupt state transitions involving irreversible loss of productivity, taking into account that such transitions in nature generally involve patterned states.
5. Rehabilitation: reversing desertification by means of periodic landscape modulations that intercept runoff (e.g. dikes) as a spatial resonance problem (analogous to forced oscillations in the time domain). 
6. Functional diversity: Derivation of community level properties and relationships, such as diversity-productivity relations, focusing on functional groups defined with respect to selected plant traits that affect ecosystem function, and taking into account the effects of herbivory (distinguishing between short and long grazing histories).

The model platform, with appropriate modifications, can be used to study community dynamics in landscapes showing geo-diversity, such as the HNR, using a meta-ecosystem modeling approach.

The two most important classes of ES in HNR are habitat and cultural services. They are related to ecological structures and functions that result in a unique high degree of geo and bio diversities.

Habitat services in HNR emerge from high degree of geodiversity. Habitat services are produced through the interactions of geological, hydrogeological, geomorphological and pedological factors and processes that create a diverse landscape mosaic that provide diverse habitats that support high biodiversity. In HNR geodiversity is crucial for producing habitat services by sustaining habitats and maintaining the lifecycle of species.

The biophysical processes that produce the habitat services have a fundamental bearing on people’s wellbeing by producing a set of cultural services. The important cultural ES in HNR are: landscape aesthetics, cultural heritage, outdoor recreation, and spiritual and religious services.

Recreation and Tourism ESs: Many people from Israel and abroad engage in in outdoor activities in HNR.  HNR outdoor activities such as walking, camping, and nature study offer an opportunity to experience and benefit cultural ES.

Landscape Aesthetics ESs: The highly diverse landscape mosaic of HNR is rich in beauty or aesthetic values represented by the various ecosystems embedded in the diverse geological and geomorphological formations.

Cultural heritage ESs: HNR include a mosaic of cultural landscapes constituents of cultural heritage characterized by the long-term (thousands years) interactions between site conditions and human cultural diversity. The cultural diversity in HNR is represented by nomadic, semi nomadic and permanent settlement cultures.

These different cultures have different heritage associations with the same ecosystem features; thus, the cultural heritage in HNR as an ES has ecological and cultural contexts. The cultural landscapes of the HNR represent arid regions cultural landscapes and can serve as a model for cultural services flow in water limited ecosystems

Spiritual and Religious ESs: HNR demonstrates spiritual and religious values as a subcategory of cultural ES. The ES are attributed to certain aspects of geo and bio diversity of the area. Holy places related to Judaism, Christianity, and Islam can be found all over the Negev highland.

We expect within the framework of ECO-potential project to construct a model of the structure and function of HNR and the ES flows emerges from HNR as a functioning ecosystem. We plan on carrying out the following steps:

1. Developing of a comprehensive theory of HNR as a hydro-geo-ecosystem. This theory will view the protected area as a life supporting "critical zone" and will integrate ideas from new disciplines such as ecohydrology, ecogeology, ecogeomorphology and ecopedology with classical ecosystem theory.
2. Based on 1, identification of key Geo-Diversity Variables (GDV) Bio-Diversity Variables (BDV) and Ecosystem Services Variables (ESV) and  the relationships and feedbacks among them based on past scientific work in the Negev highlands.
3. Based on 1and 2, identification of knowledge gaps related to GDV BDV ESV.
4. Establishment of new EO and field studies to test hypothesis on emergent ecosystem properties driven by the interactions among GDV, BDV and ESV.
5. Construction of a mathematical model of HNR as a hydro-geo-eco system based on network and pattern formation theories.
6. Model simulation of scenario of changes in relation to climate change projections of  higher frequency and magnitude of drought  events to get insight on HNR responses to climate change.
7. Identification of the relationships between HNR responses to environmental changes and the flow of ES.

In addition to the opportunity to development of HNR model within ECO-potential project  we see the study of HNR as an opportunity to develop a more comprehensive framework concerning habitat and cultural ES.

Click here to download a poster of the protected area.