A multi-temporal phenology based classification approach for Crop Monitoring in Kenya

The SBAM (Satellite Based Agricultural Monitoring) project, funded by the Italian Space Agency aims at: developing a validated satellite imagery based method for estimating and updating the agricultural areas in the region of Central-Africa; implementing an automated process chain capable of providing periodical agricultural land cover maps of the area of interest and, possibly, an estimate of the crop yield. The project aims at filling the gap existing in the availability of high spatial resolution maps of the agricultural areas of Kenya. A high spatial resolution land cover map of Central-Eastern Africa including Kenya was compiled in the year 2000 in the framework of the Africover project using Landsat images acquired, mostly, in 1995. We investigated the use of phenological information in supporting the use of remotely sensed images for crop classification and monitoring based on Landsat 8 and, in the near future, Sentinel 2 imagery. Phenological information on crop condition was collected using time series of NDVI (Normalized Difference Vegetation Index) based on Landsat 8 images. Kenyan countryside is mainly characterized by a high number of fragmented small and medium size farmlands that dramatically increase the difficulty in classification; 30 m spatial resolution images are not enough for a proper classification of such areas. So, a pan-sharpening FIHS (Fast Intensity Hue Saturation) technique was implemented to increase image resolution from 30 m to 15 m. Ground test sites were selected, searching for agricultural vegetated areas from which phenological information was extracted. Therefore, the classification of agricultural areas is based on crop phenology, vegetation index behaviour retrieved from a time series of satellite images and on AEZ (Agro Ecological Zones) information made available by FAO (FAO, 1996) for the area of interest. This paper presents the results of the proposed classification procedure in comparison with land cover maps produced in the past years by other projects. The results refer to the Nakuru County and they were validated using field campaigns data. It showed a satisfactory overall accuracy of 92.66 % which is a significant improvement with respect to previous land cover maps

Auditioning for empathy:dance, acting, and psychology students

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Planktic foraminiferal response to early Eocene carbon cycle perturbations in the southeast Atlantic Ocean (ODP Site 1263)

At low latitude locations in the northern hemisphere, striking changes in the relative abundances and diversity of the two dominant planktic foraminifera genera, Morozovella and Acarinina, are known to have occurred close to the Early Eocene Climatic Optimum (EECO; ~ 49–53 Ma). Lower Eocene carbonate-rich sediments at Ocean Drilling Program (ODP) Site 1263 were deposited on a bathymetric high (Walvis Ridge) at ~ 40° S, and afford an opportunity to examine such planktic foraminiferal assemblage changes in a temperate southern hemisphere setting. We present here quantified counts of early Eocene planktic foraminiferal assemblages from Hole 1263B, along with bulk sediment stable isotope analyses and proxy measurements for carbonate dissolution. The bulk sediment δ13C record at Site 1263 resembles similar records generated elsewhere, such that known and inferred hyperthermal events can be readily identified. Although some carbonate dissolution has occurred, the well-preserved planktic foraminiferal assemblages mostly represent primary changes in environmental conditions. Our results document the permanent decrease in Morozovella abundance and increase in Acarinina abundance at the beginning of the EECO, although this switch occurred ~ 165 kyr after that at low-latitude northern hemisphere locations. This suggests that unfavourable environmental conditions for morozovellids at the start of the EECO, such as sustained passage of a temperature threshold or other changes in surface waters, occurred at lower latitudes first. The remarkable turnover from Morozovella to Acarinina was widely geographically widespread, although the causal mechanism remains elusive. In addition, at Site 1263, we document the virtual disappearance within the EECO of the biserial chiloguembelinids, commonly considered as inhabiting intermediate water depths, and a reduction in abundance of the thermocline-dwelling subbotinids. We interpret these changes as signals of subsurface water properties, perhaps warming, and the associated contraction of ecological niches

Dextral to sinistral coiling switch in planktic foraminifer Morozovella during the Early Eocene Climatic Optimum

Coiling direction is a basic characteristic of trochospiral planktic foraminifera. Modifications in the coiling direction within ancient planktic foraminiferal populations may reflect important changes in evolution or environment, yet they remain scarcely discussed. Here we investigate fluctuations in the coiling direction within Morozovella assemblages from sections that span the interval of peak Cenozoic warmth, the Early Eocene Climatic Optimum (EECO; ~53-49 million years ago, Ma), at Atlantic Ocean Drilling Program (ODP) sites 1051, 1258 and 1263. The surface-dwelling genus Morozovella is of particular interest because it dominated tropical-subtropical early Paleogene assemblages then suffered an abrupt and permanent decline in abundance and taxonomic diversity at the start of the EECO. At all ODP sites, morozovellids display a dominant dextral coiling preference during the interval preceding the EECO. However, all the Morozovella species at all sites modify their coiling from preferentially dextral to sinistral coiling within the EECO < 200 kyr after the K/X event (~52.8 Ma), providing a new biostratigraphic tool for correlation. We also document that before the major shift in morozovellid coiling, transient excursions to higher abundances of sinistral tests occurred in conjunction with negative carbon isotope excursions. Significantly, carbon isotope data reveal that sinistral morphotypes belonging to the same morphospecies typically have lower 13C values. The dominance of sinistral morphotypes, at the expense of dextral forms within the EECO, coupled with the lower 13C signatures of the former, suggests that the sinistral forms were less dependent on their photosymbiotic partnerships and thus able to adapt more readily to paleoceanographic change at the EECO. The observed sinistral and dextral coiling of morozovellids can be a genetically heritable characteristic that lies within cryptic speciation across multiple morphologically defined species. Alternatively the coiling changes were exclusively ecophenotypic responses whereby different species were able to preferentially adopt sinistral coiling in reaction to the changed conditions in the mixed-layer during the EECO. Previous interpretations of coiling flips in planktic foraminifera in the early Eocene, especially including morozovellids, have favoured a genetic explanation rather than an ecological response. Our present data cannot validate or disprove this idea, but should stimulate renewed thought on the matter

Demise of the Planktic Foraminifer genus Morozovella during the Early Eocene Climatic Optimum: new records from ODP Site 1258 (Demerara Rise, western equatorial Atlantic) and Site 1263 (Walvis Ridge, South Atlantic)

Here we present relative abundances of planktic foraminifera that span the Early Eocene Climatic Optimum (EECO) at Ocean Drilling Program (ODP) Site 1258 in the western equatorial Atlantic. The EECO (~53.3−49.1 Ma) represents peak Cenozoic warmth, probably related to high atmospheric CO2, and when planktic foraminifera, a dominant component of marine sediment, exhibit a major biotic response. Consistent with previous work, the relative abundance of the genus Morozovella, which dominated early Paleogene tropical-subtropical assemblages, markedly and permanently declined from a mean percentage of ~32% to less than ~7% at the beginning of the EECO. The distinct decrease in Morozovella abundance occurred at Site 1258 within ~20 kyr before a negative excursion in δ13C records known as the J event and which defines the beginning of EECO. Moreover, all morozovellid species except M. aragonensis dropped in abundance permanently at Site 1258, and this is related to a reduction in test-size. Comparing our data with that from other locations, the remarkable switch in planktonic foraminifera assemblages appears to have begun first with unfavourable environmental conditions near the Equator and then extended to higher latitudes. Several potential stressors may explain observations, including some combination of algal photosymbiont inhibition (bleaching), a sustained increase in temperature, or an extended decrease in pH

Sessistenza come resistenza: la trans-ontologia di Jean-Luc Nancy in dialogo con il trans-femminismo

La co-ontologia heideggeriana viene fatta scivolare, dalla filosofia di Jean-Luc Nancy, lungo il piano inclinato della vita vissuta e concreta degli esseri-umani-inrelazione che coabitano lo spazio sociale, una dislocazione che avviene nel segno della porosità e penetrabilità del “con-essere” che rappresenta la chiave di volta del suo libro, Sessistenza. In questo testo, il corpo, il toccare, il sesso sono sporgenze che costellano una mappa concettuale frutto di una lunga militanza filosofica contrassegnata da un’autentica ontologia aptica, cifra segnante di un pensiero della relazionalità, dell’interdipendenza, della vulnerabilità sessistenziale, che connota i corpi in con-tatto che tutti e tutte siamo. Assumendo la lezione di Derrida che rilegge il Dasein come “disseminazione”, Nancy elabora una transontologia attraverso cui si manifesta la r-esistenza della sessistenza, vale a dire quel rifiuto caparbio dei corpi distinti e differenti all’omologazione e all’uniformità dell’identico e dell’identitario condiviso dal trans-femminismo che della combinatoria inesauribile dei sessi fa il proprio punto di forza. Così, tanto per l’approccio sessistenziale che per quello transfemminista, al cuore di ogni teoria vi sono le vite e le pratiche di corpi sessuati distinti e differenti in rel-azione.  The Heideggerian co-ontology is slipped, by the philosophy of Jean-Luc Nancy, along the inclined plane of the lived and concrete life of human-beingsin- relationship who cohabit the social space, a dislocation that takes place in the sign of porosity and penetrability of the “con-being” which represents the keystone of his book, Sexistence. In this text, the body, the touch, the sex are protrusions that dot a conceptual map that is the result of a long philosophical militancy marked by an authentic haptic ontology, a sign of a thought of relationality, interdependence and sexistencial vulnerability that connotes the bodies in contact that we all are. Taking up the lesson of Derrida who reinterprets Dasein as “dissemination”, Nancy elaborates a trans-ontology through which the r-existence (Resistance) of sexistence is manifested, that is to say that stubborn rejection of distinct and different bodies to the homologation and uniformity of the identical and of the identity shared by trans-feminism which makes its strong point of the inexhaustible combinatorics of the sexes. Thus, both for the sexistencial approach and for the transfeminist one, at the heart of every theory are the lives and practices of distinct and different sexual bodies in relation

Potere erotico e sessistenza: Jean-Luc Nancy con Audre Lorde

L’accostamento che opera Jean-Luc Nancy tra l’“indeterminatezza della pulsione” e l’“inadeguatezza del linguaggio” che tenta di descriverla, accomuna nella medesima “destinerranza” il senso e il sesso (oltre che il senso del sesso), in quanto entrambi inattingibili e incommensurabili. Lo sfuggirsi del sesso e del linguaggio marca l’ontologia erotica o la filosofia sessistenziale con cui Nancy cerca di dar conto della relazione d’intimità tra persone come evento perspicuo, interattivo e trasformativo. In tal senso, una lettura del concetto di “sessistenza” attraverso quello di “potere erotico” messo a punto da Audre Lorde dimostra la centratura genuinamente ontologica e l’immenso potenziale trasformativo che, sia per il filosofo francese che per la teorica lesbo-femminista afroamericana, ha l’esperienza sessuale che connette gli esseri umani. La capacità di Nancy di pensare il sesso al di là dei generi (egli si riferisce in Sessistenza proprio al “potere erotico” di Lorde come evento rivoluzionario e liberatorio) fa così segno al rapporto piuttosto che ai soggetti che lo ingaggiano. The juxtaposition that Jean-Luc Nancy makes between the “indeterminacy of the drive” and the “inadequacy of the language” that attempts to describe it, lumps sense and sex (as well as the sense of sex) together in the same “destinerrancy,” as both unattainable and incommensurable. The elusiveness of sex and language marks the erotic ontology or sexistential philosophy with which Nancy seeks to account for the relationship of intimacy between persons as a perspicuous, interactive and transformative event. In this sense, a reading of the concept of “sexistence” through that of “erotic power” developed by Audre Lorde demonstrates the genuinely ontological centering and immense transformative potential that, for both the French philosopher and the African-American lesbian-feminist theorist, the sexual experience that connects human beings has. Nancy’s ability to think sex beyond genders (he refers in Sexistence precisely to Lorde’s “erotic power” as a revolutionary and liberating event) thus makes a mark on the relationship rather than on the subjects who engage it

Constraints on crustal recycling from boron isotopes in Italian melt inclusions

Boron represents an important tracer of crustal recycling processes in subduction zones, because it is readily mobilised from the subducted lithosphere and different components in the slab are isotopically distinct. Profiles of boron content and isotope ratio across magmatic arcs generally show that B concentrations decrease with increasing slab depth, which implies decreasing amount of slab-derived fluids. To date, however, data on continental-collision zones and post-collisional subduction settings are scarce. This study examines Plio-Quaternary Italian magmatism to quantify crustal recycling in a complex subduction setting. Magmatic products vary from (ultra)potassic along the Tyrrhenian side in the north, to calcalkaline and Na-alkaline in the south. Combined major and trace element and [B] content and δ11B values are reported in 99 Melt Inclusions (MIs), analyses from a wide range of Italian lavas. [B] vary from 4 to 298 µg/g and δ11B from -29.2 to -3.9‰. The B isotopic values are considerably lower than previously reported in arcs and other post-collisional setting magmatism. We infer a role for phengite in the source of all studied Italian magmas (with the exception of Mt. Etna lavas). This white mica is stable to high pressures in subducted sediments of altered oceanic crust and records dehydration and 11B depletion due to dehydration processes. MIs hosted in highly fosteritic olivines (Fo &gt;74; median of 89) from across Italy reveal that primary melts tap heterogeneous mantle including subducted oceanic and continental components that were introduced during the Alpine, and Adriatic and Ionian subduction phases. The combined geochemical data record the involvement of sediments that variably metasomatized the mantle wedge. We propose that slab detachment and consequent heat input from the inflow of hot asthenosphere was responsible for phengite breakdown in subducted sediments and locally produced metasomatism of the mantle wedge, imposing a characteristic B isotope signature to the overlying mantle. Continued heating due to asthenosphere inflow led to melting of the metasomatized mantle wedge and generation of the Italian magmatism. Mt. Etna represents an exception being dominated by asthenosphere upwelling through a slab window with minimal influence from active subduction.</p