Search results for "Soil temperature"

Assessment of the SMAP Level-4 Surface and Root-Zone Soil Moisture Product Using In Situ Measurements

2017

International audience; The Soil Moisture Active Passive (SMAP) mission Level-4 Surface and Root-Zone Soil Moisture (L4_SM) data product is generated by assimilating SMAP L-band brightness temperature observations into the NASA Catchment land surface model. The L4_SM product is available from 31 March 2015 to present (within 3 days from real time) and provides 3-hourly, global, 9-km resolution estimates of surface (0-5 cm) and root-zone (0-100 cm) soil moisture and land surface conditions. This study presents an overview of the L4_SM algorithm, validation approach, and product assessment versus in situ measurements. Core validation sites provide spatially averaged surface (root zone) soil m…

Prediction of germination rates of weed species: Relationships between germination speed parameters and species traits

2011

International audience; In fields, the timing of weed emergence flushes is mostly related to the timing and rate of seed germination, which depend on seed dormancy level, soil temperature and water potential conditions as well as soil tillage and crop sowing date. Seed germination parameters are essential in weed dynamics models to account for the effects of soil conditions on weed demography. Since these parameters are difficult to measure, our objective was to test the possibility of estimating them from easily accessible information. Seed germination parameters (germination lag-time, time to mid-germination and mid-germination rate) were measured or collected from the literature for 25 w…

The role of the aquifer in soil CO2 degassing in volcanic peripheral areas: A case study of Stromboli Island (Italy)

2017

Abstract The peripheral area of Stromboli Island, Italy, named “Scari”, was continuously studied between January 2009 and December 2010. Data on soil CO 2 flux and the partial pressure of CO 2 (pCO 2 ) in equilibrium with the thermal aquifer linked to the magmatic system are presented. Soil CO 2 fluxes range from 20 to 370 g m − 2  d − 1 and have been strongly affected by soil temperature variations. Soil CO 2 flux data were filtered with respect to the soil temperature and the calculated values, called “residuals”, were considered to detect changes induced by the magmatic system. The pCO 2 values change in a wide range from 0.03 to 0.6 (atm), showing rapid variations. The results of this s…

Effects of Soil Solarization With Different Plastic Films and Fumigation With Combination of 1,3-Dichloropropene and Chloropicrin on Strawberry Prote…

2012

Polyethylene and Biodegradable Starch-Based Mulching Films Affect Winter Melon Production in a Mediterranean Area

2012

Polyethylene and Biodegradable Starch-Based Mulching Films Positively Affect Winter Melon Production in Sicily

2014

Plastic mulching is widely used in many regions of the world for growing melons. The winter melon is largely grown in the hilly countryside of the Mediterranean island of Sicily (Italy) where mulching plastic films enhance early and total yields. However, removing and disposal of polyethylene plastic mulches after use represent a major disadvantage and an environmental concern. The objective of this trial was to compare the effects of polyethylene (PE) (transparent and black) and biodegradable (black) mulching films on yield, fruit size and quality of melon grown in the open field. The trial was conducted in the north-western coast of Sicily in the province of Trapani, 250-m elevation. Melo…

SMOS REFLEX 2003: L-band emissivity characterization of vineyards

2005

The goal of the Soil Moisture and Ocean Salinity mission over land is to infer surface soil moisture from multiangular L-band radiometric measurements. As the canopy affects the microwave emission of land, it is necessary to characterize different vegetation layers. This paper presents the Reference Pixel L-Band Experiment (REFLEX), carried out in June-July 2003 at the Vale/spl grave/ncia Anchor Station, Spain, to study the effects of grapevines on the soil emission and on the soil moisture retrieval. A wide range of soil moisture (SM), from saturated to completely dry soil, was measured with the Universitat Polite/spl grave/cnica de Catalunya's L-band Automatic Radiometer (LAURA). Concurre…

An Overview of the Regional Experiments for Land-Atmosphere Exchanges 2012 (Reflex 2012) Campaign

2015

The REFLEX 2012 campaign was initiated as part of a training course on the organization of an airborne campaign to support advancement of the understanding of land-atmosphere interaction processes. This article describes the campaign, its objectives and observations, remote as well as in situ. The observations took place at the experimental Las Tiesas farm in an agricultural area in the south of Spain. During the period of ten days, measurements were made to capture the main processes controlling the local and regional land-atmosphere exchanges. Apart from multi-temporal, multi-directional and multi-spatial space-borne and airborne observations, measurements of the local meteorology, energy…

Weed communities of rice fields in the central Pamir Alai Mountains (Tajikistan, Middle Asia)

2013

The study present results of geobotanical investigations conducted in rice fields in the central Pamir Alai Mts (Tajikistan, Middle Asia), mainly within Syr-Daria, Pyandzh, Zeravshan, Kafirnigan, Khanaka and Surkhandaria river valleys in the years 2009–2011. The researches were focused on classification of plant communities developing within this poorly investigated area. Habitat conditions were checked including conductometry, pH reaction, temperature, depth of water and, for several plots, also soil structure. Altogether 114 phytosociological relevés using the Braun-Blanquet method were sampled. The analyses classified the vegetation into 28 communities including 24 associations. Five new…

Nitrogen-fixing cushion Astragalus siculus modulates soil fertility, microclimate, plant facilitation, bacterial and fungal microbiota along an eleva…

2023

Question: Cushion-forming vascular plants are adapted to alpine environments and act as ecosystem engineers by moderating microclimate and creating a fertility island under their canopy. Most of the available studies on cushion ecology have been devoted to plant facilitation, but none used a holistic approach that considers the response of co-existing plant species with other key ecosystem players. Here, we quantified the biogenic effect and facilitation capacity of Astragalus siculus, a spiny nitrogen-fixing cushion plant, and test the hypothesis that the facilitation effect would increase with elevation as stress gradient.Location: Mount Etna, the highest active volcano in the Mediterrane…