Holocene alluvial morphopedosedimentary record and environmental changes in the Bardenas Reales Natural Park (NE Spain)

A Holocene alluvial morphostratigraphy, based on geomorphological mapping, sedimentological analysis, soil development and radiocarbon chronology is presented for the semiarid Blanca basin in the Bardenas Reales Natural Park (NE, Spain). Four morphopedosedimentary alluvial units (MU1, MU2, MU3 and MU4) were differentiated, which may correspond to two palaeogeographical stages. The first one includes the morphopedosedimentary unit MU1 and is the most extensive in the area. It is made up of a complex aggradation (fill up) sequence comprising a braided channel system, a sand–mud flat (9200–7900 cal BP) and a playa-lake environment related to a nearly closed depression. An intensive fluvial entrenchment period is recognized, leading the opening of the Blanca basin, before the second stage that includes the units MU2, MU3 and MU4. This set of units forms a sequence of cut-and-fill and nested fill terraces recording the alluvial activity in the Blanca basin during the last 6 ka. The MU2 unit, 5900–3300 cal BP in age, represents a period of high geomorphic instability with rapid alluvial sedimentation/channel incision oscillating changes. On the other hand, the MU3 unit has an age of 1050–500 cal BP and appears as a thin extensive alluvial cover overlying previous units. Finally, the MU4 unit comprises superposition of numerous flood depositional sequences, centimetric in scale, dated from 450–10 cal BP. The established soil chronosequence supports the numerical chronology of the four units. These accumulation periods (MU1, MU2, MU3, MU4) are associated with dry phases and/or high hydrological variability (floods and droughts) at a regional scale. Changes on the North Atlantic atmospheric circulation mode over Southern Europe may provide the key to explain the nature of alluvial activity during Holocene in Bardenas Reales.     

Comparison of DOP and DRIS Methods for Leaf Nutritional Diagnosis of Vitis vinifera L., Cv. Tempranillo

Deviation from optimum percentage (DOP) and Diagnosis and Recommendation Integrated System (DRIS) are methodologies for leaf analysis interpretation. DOP calculates the deviation as a percentage for each essential element while DRIS calculates the average deviation for different ratios that include each element. A vine survey was undertaken for 11 years in La Rioja, northeastern Spain, to establish nutritional references for cv. ‘Tempranillo’ (Vitis vinifera L.). Diagnosis of nitrogen, phosphorus, potassium, calcium, and magnesium were performed by DRIS and DOP on the dataset for leaf blade and petiole, at both flowering (n = 684) and veraison (n = 801) with a moderate-yield criterion (3,800–10,000 kg·ha^?1). Important differences between DOP and DRIS were found when a diagnosis using the same dataset was performed. In spite of the differences, the regression equations obtained are an acceptable adjustment between both methods for phosphorus (P) and magnesium (Mg) in blades and petioles, and for potassium (K) in blades.     

Is light the key factor for success of tube shelters in forest restoration plantings under Mediterranean climates?

Tube shelters were designed to protect against browsing, but they improve seedling survival in Mediterranean dry climates. Mechanisms for this response, however, are not fully understood and this knowledge can be useful to help design optimal tube shelters for Mediterranean species and climates. Our objective in this study was to determine if the positive effect of tube shelters is due to enhanced growth during the wet season or to reduced light stress during the dry season. We performed two independent experiments. In the first, we assessed root growth during the wet season in two Mediterranean species with contrasting light tolerance (Quercus ilex L. and Pinus halepensis Mill.) growing in tubes with varying light transmissivity. In the second experiment, we studied the response of a Quercus ilex plantation to different shelter treatments. Root growth during the wet season was reduced with decreasing light transmissivity in the shade intolerant P. halepensis, but not in the shade tolerant Quercus ilex. Survival of Q. ilex shaded by a mesh shelter only during summer was higher than in unsheltered seedlings and similar to the survival in tube and mesh shelters during the whole season. This suggests that shade during the dry period was the main factor explaining survival in this species. This effect could be related to the lower leaf temperature recorded in sheltered seedlings. We conclude that Q. ilex (and perhaps other late successional, shade tolerant Mediterranean species) should be planted in tubes with the currently used light transmissivity because these shelters reduce light stress in summer without impairing root growth in the wet season. However, current tubes impair root growth in P. halepensis (and likely other pioneer, shade intolerant Mediterranean species), so higher transmissivity tubes may be necessary. Optimal transmissivity for tube shelter in Mediterranean climates is species-specific and identifiable as the point that minimizes light stress during summer without impairing root growth in the wet season.     

Physiological and population genetic analysis of Botrytis field isolates from vineyards in Castilla y León,Spain

Grey mould is reported in the vineyards of Castilla y León, Spain, every year. However, the natural populations of the pathogen have yet to be properly characterized. Vineyards from six wine-producing areas were surveyed in 2002 and 2007, sampling from bunches of grapes with and without symptoms. A total of 283 Botrytis field isolates were selected for physiological and genetic analyses. Botrytis cinerea isolates predominated in the population, although isolates belonging to Botrytis pseudocinerea and Botrytis prunorum were also identified. These two species are recorded for the first time in Spain in this work. In addition, two isolates closely related to Botrytis californica were identified. Physiologically, the B. cinerea population is very diverse, displaying a normal distribution of aggressiveness values in Vitis vinifera leaves, suggesting a quantitative nature for this trait. Several isolates unable to cause infection were identified, most of them belonging to a mycelial morphotype. Population genetic analysis revealed that genotypic diversity is high and that multiple infections of the same bunch of grapes by different genotypes occur frequently. The high genotypic diversity observed, an even distribution of both mating types and the linkage disequilibrium values detected support a mixed mode of reproduction with low levels of clonality. The wine-producing area in which each isolate was collected imposed a low degree of population differentiation, an effect that does not depend solely on the geographic distances but rather on the management practices used by growers and wine producer associations.     

Exploring sense of place across cultivated lands through public participatory mapping

Context

Cultivated lands have undergone a shift towards intensification and increased productivity, favoring provisioning services at the expense of regulating and cultural services. Cultivated lands have rarely been researched as a provider of cultural services.

Objectives

The overarching goal of this study is to assess sense of place across cultivated lands. To do so, we used participatory mapping to elicit public knowledge of the past and present coverage of agricultural areas, as well as to reveal the public sense of place attached to cultivated lands and perceptions about future land-use pathways.

Methods

This study was conducted in an agrarian and rural region of SE Madrid (Spain), where we did ecosystem service participatory mapping workshops with key stakeholders related to the agrarian sector: farming professionals, land-use decision-makers and planners and other local actors.

Results

We identified linkages between cultivated lands and sense of place as a key cultural service. The locations most pinpointed for its sense of place overlapped with cultivated lands. The future land-use pathways that showed the highest agreement between the likelihood and interest in their promotion were the increases in green and/or protected areas and orchards. Extensive crops and urban areas the land-use pathways with the highest dissonance.

Conclusions

The results encourage land planners and researchers to approach landscape values in relation to the sense of place. We concluded that cultivated lands present a sense of place, and this link has the possible to root society in agricultural landscape through the establishment of belongingness, stewardship and care connections.

     

In vitro antiprotozoal activity of the leaves of Artemisia ludoviciana

The inhabitants of Northeast of Mexico use an infusion of leaves from Artemisia ludoviciana as an antidiarrheal remedy. The aqueous, methanol, acetone and hexane leaf extracts from mature plants were found to be active in vitro against the parasitic protozoa Entamoeba histolytica and Giardia lamblia.     

Component analysis of duration from seeding to heading in rice by the basic vegetative phase and the photoperiod-sensitive phase

Summary Inheritance of the duration from seeding to heading in rice was analyzed by dividing the vegetative growth period into the basic vegetative phase (b.v.p.) and the photoperiod-sensitive phase (p.s.p.). Concurrent determination of the two physiologic phases on pure lines and hybrids was facilitated by testing vegetative tillers of the same plant under two photoperiods.In nine crosses of photoperiod-sensitive by insensitive arieties where the parents differed appreciably in b.v.p. estimates obtained under a 10-hour photoperiod, two to three Ef genes of relatively discrete effect controlled the F₂ variation in b.v.p. Short b.v.p. was controlled by dominant genes of cumulative but unequal effect. In three other sensitive × insensitive crosses where the parents differed less in b.v.p., the F₂ segregation could be ascribed to two to four pairs of metrical alleles with equal or unequal effect.Concurrent data obtained from sensitive × insensitive crosses grown under a 16-hour photoperiod indicate the action of one or two (duplicate) dominant Se genes in controlling strong sensitivity to a long photoperiod. One insensitive variety appeared to carry a recessive inhibitor, i-Se. The Se gene(s) is epistatic to the Ef genes in the expression of earliness under a short photoperiod. Pooled data also suggest an association between photoperiod sensitivity and a short b.v.p. in a large proportion of F₂ plants.Field data on the two principal components of the vegetative growth period obtained under natural daylength generally indicated agreement with duplicate plantings grown under controlled photoperiods. Segregation for the optimum photoperiod and critical photoperiod under a changing photoperiod in the field plantings probably resulted in modified expression of the Se and Ef genes.Research supported in part by grant GB-2417 from the U.S. National Science Foundation.