Long term degradation and rapid restoration of the Negev’s Agroecosystems –lessons learned towards sustainable dryland management Dr. Stefan Leu Desert Research Institutes, Sde Boker, Israel

Israel’s Negev region is amongst the longest populated dryland areas in the world, featuring uncountable archeological artefacts yet to be evaluated, witnessing human exploitation and agricultural technologies over at least the last 10000 years, though the area was considered a worthless waste land when re-discovered in the early twentieth century. Featuring large urban centers (Beer Sheba, Arad) continuously populated at least between 8000 – 2000 years ago, and numerous Roman/Nabatean towns 1500 – 2500 years ago inside the arid regions of the Central Negev, the area was evidently and successfully used for agriculture supporting large and diverse human populations employing various and growingly more sophisticated agricultural and water harvesting technologies during periods of strong variations in precipitation. We will present a number of novel archaeological indications from the Hura area and near Yeruham including Bronze age and Byzantine settlement activity, and sophisticated water engineering, evolving into complex and large scale irrigation schemes. Those finds indicate that, independent of significant variations in rainfall in the course of the millennia, the Central Negev was a densely populated and well developed dryland community. As we hypothesized in the past, its current deserted status is the result of human mismanagement, wars, migration and plagues rather that the impact of any dramatic recent climate changes, and proper management could restore the Negev’s diversity, ecology and agricultural productivity. Our small scale pilot studies and empirical comparisons between conserved Negev locations and the surrounded highly degraded landscapes confirmed this hypothesis. A pilot scale 30 hectare ecosystem restoration program was therefore initiated by Project Wadi encouraging soil quality improvements, erosion control and ecological recovery accompanied by detailed scientific assessment of the recovery process (https://www.sustainabilitylabs.org/ecosystem-restoration/).

The results of this project indicate that five years of conservation from grazing and tilling, supported by tree planting and erosion control, increased the annual herbaceous biomass productivity 5-fold compared to untreated control plots, dramatically enriched plant and animal biodiversity, rapidly increased the moisture content of the soil by 50%, enriched soil nutrients content and induced rapid sequestration of CO2 into soil organic matter. This proves that most of the Negev is profoundly degraded and can rapidly be rehabilitated into a far more diverse and productive agroecosystem addressing all UN environmental conventions and most SDGs. We will discuss local and global implications for global dryland communities and the environment.