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The objective of this study was to identify the physiological mechanisms used by Cistus heterophyllus Desf. Subsp. carthaginensis (Pau) M. B. Crespo & Mateo, a species in critical danger of extinction, to cope with two typical abiotic conditions. During the summer of 2021, plants were cultivated under a shade mesh that intercepted 50% of the incident solar radiation (SHADE) and in natural conditions (SUN). Three irrigation treatments were also applied: control, T1, moderate water deficit; T2, 60% of the control, severe deficit; and T3, 30% of the control. Therefore, there were six treatments (SUN-T1, SUN-T2, SUN-T3, SHADE-T1, SHADE-T2, SHADE-T3). Plants were more affected by solar radiation than by deficit irrigation. Although leaf water potential, stomatal conductance and root biomass decreased by up to 45%, 63% and 65%, respectively, as deficit irrigation increased, plants were able to develop a leaf osmotic adjustment and an improved intrinsic water-use efficiency to maintain their growth and survival rate. Shade conditions improved gas exchange, reduced leaf temperature and induced the synthesis of chlorophylls, regardless of the irrigation level imposed. This indicated that radiation was the most limiting factor in our experiment. Applying 50% of the radiation and a moderate water deficit would help to obtain a good plant development and high survival rate in future recovery and conservation programs for the species. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify the physiological mechanisms used by Cistus heterophyllus Desf. Subsp. carthaginensis (Pau) M. B. Crespo & Mateo, a species in critical danger of extinction, to cope with two typical abiotic conditions. During the summer of 2021, plants were cultivated under a shade mesh that intercepted 50% of the incident solar radiation (SHADE) and in natural conditions (SUN). Three irrigation treatments were also applied: control, T1, moderate water deficit; T2, 60% of the control, severe deficit; and T3, 30% of the control. Therefore, there were six treatments (SUN-T1, SUN-T2, SUN-T3, SHADE-T1, SHADE-T2, SHADE-T3). Plants were more affected by solar radiation than by deficit irrigation. Although leaf water potential, stomatal conductance and root biomass decreased by up to 45%, 63% and 65%, respectively, as deficit irrigation increased, plants were able to develop a leaf osmotic adjustment and an improved intrinsic water-use efficiency to maintain their growth and survival rate. Shade conditions improved gas exchange, reduced leaf temperature and induced the synthesis of chlorophylls, regardless of the irrigation level imposed. This indicated that radiation was the most limiting factor in our experiment. Applying 50% of the radiation and a moderate water deficit would help to obtain a good plant development and high survival rate in future recovery and conservation programs for the species.

The aim of this study was to investigate the physiological and hydric adaptability of Pistacia lentiscus (lentisco) to saline irrigation conditions. Plants of lentisco were subjected to four salinity treatments in the irrigation water (0, 50, 100 y 150 mM NaCl) during three months in a growth chamber in order to identify possible tolerance mechanisms to salinity stress. The results showed a reduction of aerial growth parameters, mainly in the 150 mM of NaCl treatment. The root biomass did not change; however, the root hydraulic conductivity was modified. This behavior was related with decreases in leaf water potential values both at morning and midday. With the increase of salinity in the irrigation water, the radial growth of stem of the plants was proportionally decreased, and Cl- and Na+ content at minimum and maximum illumination in leaves and roots increased. Stomatal conductance decreased in the plants with higher salinity level, although chlorophyll content and fluorescence were not affected by the salinity treatments. Although the growth rates were statistically affected in all the treatments, the plants were able to resist the salt stress through changes in the leaf structures, related to a reduction of water losses via transpiration.

Communities are increasingly threatened by extreme weather events. The cumulative effects of such events are typically investigated by assessing community resilience, that is, the extent to which affected communities can achieve pre‐event states. However, a mechanistic understanding of the processes underlying resilience is frequently lacking and requires linking various measures of resilience to demographic responses within natural communities.Using 13 years of data from a shrub community that experienced a severe drought in 2005, we use generalized additive models to investigate temporal changes in three measures of resilience. We assess whether community‐weighted, species‐specific demographic traits such as longevity and reproductive output can predict changes in resilience and how the performance of these traits compares to more commonly used plant functional traits such as leaf area or root dry matter content.We find significant spatiotemporal variation in community dynamics after the drought. Overall, demographic traits are better at predicting absolute and relative resilience in total plant cover, but functional traits outperform demographic traits when resilience in community composition is assessed. All resilience measures show nonlinear and context‐specific responses to demographic and functional traits; and these responses depend strongly on the severity of initial drought impact.Synthesis. Our work demonstrates that a full picture of the mechanisms underlying community responses to drought requires the assessment of numerous species‐specific characteristics (including demographic and functional traits) and how these characteristics differentially affect complementary measures of community changes through time. [ABSTRACT FROM AUTHOR]

• Water conservation in landscape is a challenge of great importance. • Water stress application led to an effective process of acclimatization to drought. • Drought tolerance was mainly related to osmotic adjustment and stomatal control. • Moderate deficit irrigation did not affect the aesthetic features of the plant. • Severe deficit irrigation resulted in stocky stress-resistant rooted cuttings. Phillyrea angustifolia is an evergreen shrub of interest for urban landscape design, as well as for use in revegetation projects in Mediterranean areas, which are characterized by an acute scarcity of water. The effect of different levels of water deficit on several physiological, ornamental and morphological parameters of Phillyrea angustifolia plants was studied to evaluate their adaptability to xerogarden and/or landscape conditions. Nursery grown plants were subjected to three irrigation treatments: a control (watered to container capacity) and two deficit irrigation treatments of 60 and 40% of the amount of water supplied in the control treatment (moderate and severe deficit irrigation). After 23 months, plant height was significantly inhibited by both water deficit treatments, although plant compactness (foliar area in relation to plant height) was not affected. Plants under severe deficit irrigation increased their root to shoot ratio and water use efficiency, which are positive aspects for hardening. Plants exposed to both deficit irrigation treatments exhibited slight dehydration throughout the experiment, especially in spring, as indicated by the lower leaf water potential and relative water content. The tolerance of P. angustifolia to drought was mainly related to adjust osmotic and regulated stomatal closure. It is concluded that both deficit irrigation treatments can be used successfully in P. angustifolia plant production to reduce water consumption while maintaining good overall quality. Moderate deficit irrigation is specially recommended for gardening purposes, since this treatment produced plants with of visual quality. Severe deficit irrigation is more suitable for landscaping purposes, as an effective nursery technique to produce plants better adapted to environmental stress during transplanting. [ABSTRACT FROM AUTHOR]

Cistus ladanifer (rockrose) is a perennial shrub quite abundant in the Mediterranean region, and it is a rich source in secondary compounds such as condensed tannins (CTs). Condensed tannins from C. ladanifer were able to change the ruminal biohydrogenation (BH), increasing the t11–18:1 and c9,t11–18:2 production. However, the adequate conditions of the C. ladanifer CTs used to optimize the production of t11–18:1 and c9,t11–18:2 is not yet known. Thus, we tested the effect of increasing the doses of C. ladanifer CT extract (0, 25, 50, 75 and 100 g/kg dry matter (DM)) on in vitro rumen BH. Five in vitro batch incubations replicates were conducted using an oil supplemented high-concentrate substrate, incubated for 24 h with 6 mL of buffered ruminal fluid. Volatile fatty acids (VFAs) and long chain fatty acids (FA) were analyzed at 0 h and 24 h, and BH of c9–18:1, c9, c12–18:2 and c9, c12, c15–18:3, and BH products yield were computed. Increasing doses of C. ladanifer CTs led to a moderate linear decrease (p < 0.001) of the VFA production (a reduction of 27% with the highest dose compared to control). The disappearance of c9–18:1 and c9,c12–18:2 as well as the production of t11–18:1 and c9, t11:18:2 was not affected by increasing doses of C. ladanifer CTs, and only the disappearance of c9, c12, c15–18:3 suffered a mild linear decrease (a reduction of 24% with the highest dose compared to control). Nevertheless, increasing the C. ladanifer CT dose led to a strong depression of microbial odd and branched fatty acids and of dimethyl acetals production (less than 65% with the highest dose compared to control), which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities, in a possible adaptative response of microbial population to stress induced to CTs and polyunsaturated fatty acids. The ability of C. ladanifer to modulate the ruminal BH was not verified in the current in vitro experimental conditions, emphasizing the inconsistent BH response to CTs and highlighting the need to continue seeking the optimal conditions for using CTs to improve the fatty acid profile of ruminant fat.

Pistacia lentiscus is a wild species that grows widely in the Mediterranean area. However, despite it appearing to be particularly resistant to some stressful conditions, drought and salinity may alter its physiological and morphological behavior. While the responses of P. lentiscus to both stresses have been partially studied, its avoidance and tolerant mechanisms are poorly understood. In particular, changes in leaf tissue cell wall and the photosynthetic activity during a prolonged water deficit and salinity are unknown. Nursery grown plants were subjected to four irrigation treatments lasting eleven months: control (1 dS m −1 , 100% water holding capacity), two deficit treatments (moderate and severe water deficit, corresponding to 60 and 40% of control) and saline treatment (4 dS m −1 , same amount of water supplied as control). Biomass accumulation was affected more by deficit irrigation than by salinity. Salt tolerance in P. lentiscus was associated with the restricted uptake of Cl − and its storage in roots. However, the cumulative effect of irrigating with saline water involved an over-accumulation of Na + and Cl − in leaves, which probably contributed to the pronounced decrease in photosynthesis, confirming the importance of the length of exposure of the plants to salt stress. Plants under saline or severe deficit irrigation exhibited slight dehydration throughout the experiment, as indicated by the lower leaf water potential and relative water content, due to the low availability of substrate water (osmotic effect). The response of plants to severe water stress, which resulted in stomatal closure and a decrease in net photosynthesis rate, involved a marked decrease in plant height and growth, especially in the first months of the experiment, after which a slight acclimation may have occurred in these plants. Under moderate water stress, most of these responses were mitigated. Salinity induced active osmotic adjustment and decreased leaf tissue elasticity. Due to its tolerance of water stress and salinity, P. lentiscus is a suitable ornamental species for gardening in arid and saline area. [ABSTRACT FROM AUTHOR]

Abstract: Energy is a major limiting factor in animal production. To plan the management of a herd in extensive grazing it is essential to monitor and understand the energy balances, in order to optimize fodder supplements. The objectives of this study were to evaluate the diet selection and to quantify the energy balance of domestic goats (Payoya goat) under semi-extensive production for the shrub understory of a pine forest in Doñana Natural Park, along the year. We used direct observation for estimating the distance traveled, speed, time consuming and diet composition. These data were transformed into kcal ingested and consumed by the goats daily in different seasons. The consumption of shrub species varied throughout the year, so grazing did not follow a fixed pattern. Goats tended to select the leaves and stem shoots in all the species, as well as the fruits of some species (dry and fleshy fruits). The results showed that grazing was able to meet the needs of goats in spring and summer but not in autumn and winter. These seasonal variations in the preferences of goats, detected by direct observation, suggest the potential utility of the understory of pine forest. So, direct observation may be an efficient and economic tool for knowing and controlling the energy balances of our grazing animals at all times. This will contribute to significant improvements in models for grazing systems, being essential in herd planning (supplements and inputs). [Copyright &y& Elsevier]

Punica granatum L. is a fruit-bearing delicious shrub or small tree, which grows from 0-700 meters height in Mediterranean climate. It is associated often with other shrubs, spreading in wide areas. This study consists in locating the areas where Punica granatum is spread in the territory of Albania. For this purpose GPS coordinates are used to show the exact areas we observed during the expeditions. In Albania, Punica granatum is spread from Hani i Hotit, in the north, to Milot in the center of the state. Pomegranate is easily found in all over the county, but not naturally, in the wild form. During the expeditions several damaged areas of Punica granatum are observed, mainly near the villages. The implementation of traditional and new management practices will be suitable for decreasing the damaged areas. [ABSTRACT FROM AUTHOR]

Abstract: The effect of different levels of water deficit and saline stress on physiological and morphological parameters in Phlomis purpurea plants was studied to evaluate their adaptability to such conditions. P. purpurea plants, grown under greenhouse conditions, were subjected to four irrigation treatments lasting 26 weeks: control (C, 1dSm−1, 100% water holding capacity), moderate water deficit (MWD, 1dSm−1, 60% of the control level of irrigation water), severe water deficit (SWD, 1dSm−1, 40% of the control level of irrigation water) and saline (S, 4dSm−1, nutrient solution containing 44mM NaCl). Aerial dry weight decreased in all three treatments, although this response was more marked in the water deficit treatments, especially SWD. Stem diameter, leaf number and leaf area were similarly reduced in both water deficit treatments, while only leaf area decreased in saline treated plants. Throughout the experiment, plant height remained similar in both control and saline treated plants but was inhibited 10 weeks after the beginning of the deficit irrigation. At the end of the experiment there were significant differences in plant height between the control and saline treatment. The control treatment produced a higher number of plants with flowers. Plants irrigated with saline water had higher Na+ concentrations in their leaves than in their roots and shoots, while the increase in the Cl− concentrations were similar in leaves and roots, suggesting some resistance to the movement of the latter ions from root to shoots. There was a negative relationship between leaf growth and Na+ concentration in the saline treated plants, in which the accumulation of salt in leaves was associated with osmotic adjustment, which was responsible for maintaining predawn and midday leaf turgor. However, no osmotic adjustment was observed in plants submitted to water stress. Root hydraulic resistance increased in SWD plants, in which the lowest leaf water potential values were recorded. In water stressed plants, in general the decrease of photosynthesis rate was mainly related with stomata factors, although the reductions observed in saline-stressed plants suggest that non-stomatal limitations to photosynthesis could also have been operating. [Copyright &y& Elsevier]

Abstract: The main objective of this study was to look into the phenotypic plasticity of the semi-deciduous Mediterranean shrub, Halimium halimifolium. We studied morphological, allocation and physiological traits to determine which characters were more plastic and contribute in a greater extent to the acclimation ability of the species. We present a phenotypic plasticity index for morphological, physiological and allocation traits, which we have applied in the most contrasted plant communities where the species grows naturally. Data published by Díaz Barradas, M.C., García Novo, F. [1987. The vertical structure of Mediterranean scrub in Doñana National Park (SW Spain). Folia Geobotanica Phytotaxonomica 22, 415–433; 1988. Modificación y extinción de la luz a través de la copa en cuatro especies de matorral en el Parque Nacional de Doñana. Monografias Instituto Pirenaico de Ecologia 4, 503–516; 1990. Seasonal changes in canopy structure in two mediterranean dune shrubs. Journal of Vegetation Science 1, 31–40.], Díaz Barradas, M.C., Zunzunegui, M., García Novo, F. [1999a. Autoecological traits of Halimium halimifolium in contrasted habitats under Mediterranean type climate. Folia Geobotanica 34, 189–208.] and Zunzunegui et al. [Zunzunegui, M., Díaz Barradas, M.C., García Novo, F. 1997. Autoecological notes of Halimium halimifolium. Lagascalia 19, 725–736. Sevilla, Spain; Zunzunegui, M., Díaz Barradas, M.C., Fernández Baco, L., García Novo, F. 1999. Seasonal changes in photochemical efficiency in leaves of Halimium halimifolium a Mediterranean semideciduous shrub. Photosynthetica 36, 17–31; Zunzunegui, M., Díaz Barradas, M.C., García Novo, F. 2000. Different phenotypic response of Halimium halimifolium in relation to groundwater availability. Plant Ecology 148, 165–174; Zunzunegui, M., Díaz Barradas, M.C., Aguilar, F., Ain-Lhout, F., Clavijo, A., García Novo, F. 2002. Growth response of Halimium halimifolium at four sites with different soil water availability regimes in two contrasted hydrological cycles. Plant and Soil 247, 271–28.] have been re-appraised and combined with original data. Phenotypic plasticity index showed that the highest plasticity of the species was physiological, and especially for the traits related with water control. This high physiological plasticity appears mainly between seasons (September–November) rather than between sites. Plasticity in allocation traits showed intermediate values between physiological and morphological traits. [Copyright &y& Elsevier]

In Mediterranean countries, where rainfall is scarce and irregular, intensive agriculture promotes erosion and nutrient losses from soil, ending eventually in contamination of water bodies. Wild shrubs may protect the soil against the erosivity of raindrops. However, some shrubs such as wild lavender are traditionally harvested by uprooting the entire plant. Thus, we studied here the impact of harvesting only a part of the plant biomass. Cultivating lavender, Lavandula lanata L., in erosion plots in Lanjar?n, Granada, Spain, we studied the effect of two harvest intensities of 25% and 50% of the plant biomass, on soil erosion, runoff, nutrient loss (NPK) and soil-water dynamics. Our results show that decreasing the harvest intensity from 50% to 25% reduced soil loss by 67%: from 143 to 46?kg soil ha-1 yr-1. Water runoff was also decreased by 59%: from 13 to 5 mm yr-1. These findings demonstrate that the rational harvest of cultivated aromatic plants protected the soil against erosion due to the reduction of soil-particle detachment by raindrop impact, and consequently avoided mechanical soil movement. Further, decreasing the harvest intensity from 50% to 25% reduced N losses by 65%, P losses by 42% and K losses by 64%. Soil-water content at 5, 10 and 20 cm deep was also higher for a harvest intensity of 25% than for a harvest intensity of 50%. In conclusion, this study supports the cultivation of lavender instead of wild harvest, following a rational harvest of biomass for reducing erosion and pollution as well as conserving soil-water content. [ABSTRACT FROM AUTHOR]

Dormancy in the hard seed coats of Mediterranean species is considered a strategy that enables persistent seed banks to be formed in the soil. An important factor related to seed coat fracture and dormancy breakage in Mediterranean ecosystems is heat. Nevertheless, the effect of factors other than heat on dormancy breakage in these species has hardly been studied. To investigate the different ecological factors involved in germination, in the laboratory we applied several scarification treatments to seeds with chromatic polymorphism. We evaluated the effect of soil seed depth during experimental burns by sowing seeds at −1, −3 and −5 cm in the soil profile, and we also studied the effect of seed origin on the posterior germination of seeds from 4 and 10 year-old shrubs as well as from the soil seed bank. U. parviflorus shows clear chromatic polymorphism: its brown seeds present higher dormancy levels than its yellow seeds. The different techniques of dormancy breakage result in different degrees of germination; the highest degree of germination is generated by the mechanical treatment, followed by the acid and the heat treatments, in that order. The depth of the seeds in the soil determines the temperature thresholds and the residence times of these temperatures and whether they stimulate a massive germination at the −1 cm soil profile or only a slight germination at the −5 cm depth. Seeds recently produced by the plant show higher dormancy levels than seeds extracted from soil seed banks. Dormancy levels also depend on the shrubland age used for extracting the soil samples (3>9 years old). In effect, from the point of view of dormancy, the germination behaviour of U. parviflorus seeds seems to follow a multiresponse strategy based on different seed populations and involving both biological and abiotic processes to break dormancy. [ABSTRACT FROM AUTHOR]

Simple Summary: Ruminant edible products have been associated with adverse health effects, due to their high saturated fatty acids and low polyunsaturated fatty acids content, resulting from the extensive biohydrogenation conducted by rumen microbiota. Cistus ladanifer condensed tannins were able to change the lamb ruminal biohydrogenation, increasing the beneficial fatty acids production. The aim of this study was to test the effect of increasing doses of C. ladanifer condensed tannins extract (0, 25, 50, 75 and 100 g/kg dry matter) on in vitro rumen fermentation and biohydrogenation. The increasing doses of condensed tannins led to a moderate decrease of volatile fatty acids production, a pronounced depression in microbial odd and branched fatty acids and of dimethyl acetals production, and a minor effect on the biohydrogenation, which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities. The ability of C. ladanifer condensed tannins extract to modulate the biohydrogenation (BH) was not observed in the present study. However, the results obtained suggest a possible adaptative response of the microbial population to stress stimuli of condensed tannins and lipid supplementation. Cistus ladanifer (rockrose) is a perennial shrub quite abundant in the Mediterranean region, and it is a rich source in secondary compounds such as condensed tannins (CTs). Condensed tannins from C. ladanifer were able to change the ruminal biohydrogenation (BH), increasing the t11–18:1 and c9,t11–18:2 production. However, the adequate conditions of the C. ladanifer CTs used to optimize the production of t11–18:1 and c9,t11–18:2 is not yet known. Thus, we tested the effect of increasing the doses of C. ladanifer CT extract (0, 25, 50, 75 and 100 g/kg dry matter (DM)) on in vitro rumen BH. Five in vitro batch incubations replicates were conducted using an oil supplemented high-concentrate substrate, incubated for 24 h with 6 mL of buffered ruminal fluid. Volatile fatty acids (VFAs) and long chain fatty acids (FA) were analyzed at 0 h and 24 h, and BH of c9–18:1, c9, c12–18:2 and c9, c12, c15–18:3, and BH products yield were computed. Increasing doses of C. ladanifer CTs led to a moderate linear decrease (p < 0.001) of the VFA production (a reduction of 27% with the highest dose compared to control). The disappearance of c9–18:1 and c9,c12–18:2 as well as the production of t11–18:1 and c9, t11:18:2 was not affected by increasing doses of C. ladanifer CTs, and only the disappearance of c9, c12, c15–18:3 suffered a mild linear decrease (a reduction of 24% with the highest dose compared to control). Nevertheless, increasing the C. ladanifer CT dose led to a strong depression of microbial odd and branched fatty acids and of dimethyl acetals production (less than 65% with the highest dose compared to control), which indicates that microbial growth was more inhibited than fermentative and biohydrogenation activities, in a possible adaptative response of microbial population to stress induced to CTs and polyunsaturated fatty acids. The ability of C. ladanifer to modulate the ruminal BH was not verified in the current in vitro experimental conditions, emphasizing the inconsistent BH response to CTs and highlighting the need to continue seeking the optimal conditions for using CTs to improve the fatty acid profile of ruminant fat. [ABSTRACT FROM AUTHOR]

This study attempts to show the dynamics of the canopy structure of the Mediterranean pioneer shrub Lavandula stoechas after man-made perturbation (i.e. grazing). The development of the vertical structure of the shrub was studied by harvesting the canopy of plants of 2 - 6 yr old in horizontal layers. The supportive biomass of the canopy was concentrated near the base at all ages. Leaf biomass was evenly distributed all over the vertical profile in 2- and 3-yr old plants. In 4-yr old plants it presented a maximum near the top of the canopy. For 5-yr old plants a structural transition started with leaf profiles showing a bimodal distribution. Leaf biomass predominated near the basein 6-yr old plants, suggesting that the transition was completed. Three canopy stages in the growth processes of the plant were recognized after the first year of growth: in the first one (from 2 to 3 yr old) both leaf and supportive biomass increased: in the second one (from3 to 4 yr) leaf biomass remained stable and there was an increase in supportive biomass until the plants reached a `mature stage', in 4-yr old plants; finally, in 5- and 6-yr old plants there wasa decrease both in leaf and supportive biomass and plant structure showed evidence of senescence. Early transitions from seedling to 1-yrold plant and from this to 2- to 3-yr old plants were less obvious.The leaf/supportive biomass ratio always decreased with plant age, from 1.88 in seedlings to 0.01 in 6-yr old plants. Biomass density followed the pattern of supportive biomass, with an increase from 1.7 g/dm3 (2-yr old plants) to 2.4 g/dm3 (4-yr old plants). Thereafter, biomass density decreased to 0.6 g/dm3 (6-yr old plants). [ABSTRACT FROM AUTHOR]