Water quantity and quality issues are accelerating the search for alternative xeriphytic and halophytic turf species. Growth and physiological responses to salinity of eight Distichlis spicata (L.) Greene genotypes were observed to elucidate salinity tolerance mechanisms operating in the species. Accession 1043 was superior in salinity tolerance to other genotypes, as indicated by percentage canopy green leaf area, relative (to control) shoot growth, relative root growth, and rooting depth, when exposed to increasing salinity up to 1.0 mol/L NaCl. Salinity tolerance was associated with complete, though minimal, shoot osmotic adjustment, maintenance of low shoot saline ion levels, and high shoot K+/Na+ ratios, all of which were facilitated by high leaf salt gland ion excretion rates.

Distichlis spicata and Suaeda aegyptiaca are two potential halophytic plant species for bioremediation of salt degraded soils, and development of saline agriculture. The physiological responses of the species to different levels of salinity (EC 0, 12, 24, 36, and 48 dS/m) in a controlled environment experiment were studied. Both species showed a high level of tolerance to elevated concentrations of salt in the irrigation water. The shoot fresh and dry weights in S. aegyptiaca increased till 36 dS/m and were sustained under 48 dS/m while in D. spicata, both parameters decreased as salinity increased. Glycine betaine accumulation did not change in D. spicata with increasing salinity, whereas proline content revealed a marked increase of 7.13 fold in 48 dS/m salinity compared to the control, which showed its critical osmoprotection role in the plant. In S. aegyptiaca, both osmolytes content significantly increased at high salinity levels (36 and 48 dS/m) up to 3.22 and 2.0 folds, respectively. Overall, S. aegyptiaca had a better potential of Na phytoremediation, and tolerated higher salinity compared to D. spicata. In contrast, the vigorous root and rhizome growth in D. spicata made it a proper solution for protecting the soils against further erosion under saline conditions.

Environmental services of biodiversity, clean water, etc., have been considered byproducts of farming and grazing, but population pressures and a move from rural to peri-urban areas are changing land use practices, reducing these services and increasing land degradation. A range of ecosystem markets have been reversing this damage, but these are not widely institutionalized, so land managers do not see them as “real” in the way they do for traditional food and fiber products. There are difficulties defining and monitoring non-food/fiber ecosystem services so they can be reliably marketed, and those markets that do operate usually do so in a piecemeal single product way in the interest of simplicity for the buyer, and seldom adequately regulate or compensate land managers for non-market benefits. New profitable uses of degraded water and regenerating land are emerging, but they require technology transfer or supply chain development to facilitate adoption. There is a need for a transformational change in the way land and water are used to promote a broader approach, so environmental services become a mainstream activity for land managers. A far-sighted Philanthropist is required to support an International institution to take up the challenge of institutionalizing such a ‘brokerage’ system to operate globally.

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