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The purpose of this experiment is to compare the growth and water consumption efficiency of five garden plants (marigold (Tagetes erecta ‘Red Brocade’), moss-rose (Portulaca grandiflora ‘Sun Rose’), dahlia (Dahlia sp. ‘Double Opra’), gazania (Gazania splendens ‘New Day’), and Indian blanket (Gaillardia pulchella. ‘Sun Dance’)) during the warmer seasons of the year under various levels of drought stress based on field capacity (FC; 25, 50, 75, and 100 %). The interaction effect of plant × drought stress (FC) on the fresh and dry mass of aerial and underground organs was significant. Decreased water availability resulted in a drop in growth parameters (leaf fresh and dry mass and leaf area). In compared to the growth of aerial organs, root biomass increased in response to drought stress. Marigold, Indian blanket, and dahlia plants had the highest root-to-shoot ratio in extreme stress, i.e., FC 25 %. The plant × drought stress interaction significantly influenced flower number, whereas flower diameter was influenced by the main effect of plant and drought stress (not their interaction). The FC 100 % and FC 25 % treatments had the highest and the lowest accumulations of proline and soluble sugars, respectively. Moss-rose, gazania, and marigold ornamental plants had the highest water use efficiency at 75 %, followed by Dahlia at 50 % and moss-rose at 25 %.

During the early Bajocian, a conspicuous coal-bearing siliciclastic succession was deposited in the northern Tabas Bock, which is important for understanding the regional geodynamics of the Central-East Iranian Microcontinent (CEIM) as well as for the Jurassic coal genesis in this part of Laurasia. Sedimentary facies analysis in a well-exposed section of the lower Bajocian Hojedk Formation (Kalshaneh area, northern Tabas Block) led to the recognition of ten characteristic sedimentary facies and three facies associations, representing channels with point bars and floodplains of a Bajocian meandering river system. Modal analysis indicates that the mature quartz arenites and quartzo-lithic sandstones of the Hojedk Formation originated from the erosion and recycling of older, supracrustal sedimentary rocks on the Yazd Block to the west. The coal petrography and maturity show an advanced maturation stage, whereas the great thickness of these continental strata points to a pronounced extension-related subsidence in the northern Tabas Block. The rapid rate of differential subsidence can be explained by accelerated normal block-faulting in the back-arc extensional basin of the CEIM, facing the Neotethys to the south. Compared to the thick Jurassic, the post-Jurassic strata are relatively thin and played a limited role in the thermal history of the coal in the northern Tabas Block. A relatively high geothermal gradient in the tectonically highly mobile area of the northern Tabas Block and/or heating by regionally widespread Palaeogene intrusions were most probably the key drivers of the thermal maturation of the Middle Jurassic coals.

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