Desertification and Land degradation

Il ciclo dell'acqua è un esempio evidente di come i cicli naturali possano venire stravolti dalle attività umane che, non solo in ambito urbano, riescono a modificarne sostanzialmente le caratteristiche. Il tentativo di dominare i fenomeni naturali, ed in particolare il ciclo idrologico, portano a volte ad effetti che sfuggono al controllo umano, come dimostrano eventi sempre più frequenti di crisi. L'acqua è l'elemento fondamentale della biosfera, decisivo per la vita, ma è anche l'elemento che stiamo distruggendo più rapidamente. La sua disponibilità costituirà in un domani prossimo il vero fattore limitante, sia sul piano quantitativo che qualitativo, scatenando nuovi conflitti. Secondo la Banca Mondiale, in un modo o nell'altro, l'acqua verrà presto spostata come avviene con il petrolio; il trasferimento massiccio di acqua sfusa potrebbe avere effetti ambientali catastrofici (Barlow e Clarke, 2002). La crisi in cui ci troviamo emerge chiaramente dalle analisi e dai conseguenti allarmi lanciati nel corso del vertice mondiale sullo sviluppo sostenibile di Johannesburg (26 agosto -4 settembre 2002). Per quanto riguarda il settore idrico, i numeri forniti dall'ONU non lasciano spazio ad equivoci: "Circa un terzo della popolazione mondiale vive in Paesi che soffrono di stress da acqua. Ottanta Paesi, in cui vive il 40% della popolazione mondiale, hanno sofferto di serie carenze d'acqua negli anni '90. La crescente richiesta d'acqua è stata causata dalla crescita della popolazione mondiale, dallo sviluppo industriale e dall'espansione dell'irrigazione in agricoltura. Per molte delle popolazioni più povere, una delle più gravi minacce ambientali alla salute rimane l'uso di acqua non trattata. Si stima che 1,1 miliardi di persone ancora non hanno accesso ad un'acqua potabile sicura e 2,4 miliardi non hanno accesso ad adeguate misure igieniche. Tali carenze provocano centinaia di milioni di casi di malattie ed oltre 5 milioni di morti ogni anno" . Uno degli aspetti in cui la crisi è maggiormente evidente è il depauperamento qualitativo delle risorse idriche superficiali. La maggior parte dell'acqua del pianeta (il 96,5%) è presente nei mari e negli oceani sotto forma di soluzione salina con un contenuto di sali che la rende poco adatta per la vita vegetale ed animale e per le attività umane. Le acque freatiche salate e salmastre e i laghi d'acqua salata ne contengono un altro 1%. Le acque dolci, cioè a basso contenuto salino, rappresentano quindi solo il 2,5% dell'acqua totale della terra. Ma la maggior parte (quasi il 70%) di questa acqua dolce si trova intrappolata nei ghiacciai o nei manti nevosi permanenti (riserve che stanno assottigliandosi sempre più a causa del riscaldamento e dei cambiamenti climatici) ed il restante si trova per lo più sottoterra, spesso in falde freatiche profonde e difficili da raggiungere. In definitiva, messi insieme, i laghi e i fiumi contengono "appena" 0,13 milioni di miliardi di tonnellate di acqua (meno dell'1% di tutta l'acqua dolce e circa lo 0,008% dell'acqua del pianeta) e ne rappresentano la parte più accessibile ma maggiormente vulnerabile, oltre che dislocata in modo ineguale sulla superficie terrestre (Montaigne, 2002). Una parte dell'acqua, circa 500.000 miliardi di tonnellate all'anno, è tenuta continuamente in moto da un ciclo di evaporazioni e condensazioni la cui energia è fornita dal sole. L'acqua che cade, in media, sulla superficie delle terre emerse è di circa 100.000 miliardi di tonnellate all'anno, una quantità che corrisponde ad uno spessore di circa 0,7 metri per ogni metro quadrato all'anno ma che, in realtà, è distribuita geograficamente e stagionalmente in maniera tutt'altro che uniforme . L'inquinamento dei nostri fiumi, torrenti e laghi, che sono il principale veicolo e il recettore finale di tutti gli inquinanti, raggiunge sempre più frequente-227

El modelo forestal con plantaciones que se ha impuesto en Chile se caracteriza por permitir y fomentar extensas plantaciones monoespecíficas coetáneas con manejo simple basado en rotaciones sucesivas y tala rasa. Estas plantaciones han generado beneficios de distinta índole, pero también han traído aparejados problemas ambientales y sociales. Empero, tales conflictos pudieron ser evitados si se hubiesen respetado los fundamentos de las ciencias forestales. Desde hace varias décadas en Chile (y antes en otras regiones del mundo), los científicos han generado y publicado información para gestionar opciones forestales adecuadas en lo ecológico, económico y social; también han alertado sobre posibles consecuencias de no aplicarla. No obstante, tal información científica no ha sido cabalmente considerada, incluso ni en la política forestal vigente, y todavía se presentan problemas en las plantaciones que denotan una escasa aplicación de ciencias forestales. Se discute una insuficiente aplicación de estas ciencias en plantaciones forestales, sus posibles causas y algunas posibles soluciones. Las plantaciones forestales requieren la aplicación de los fundamentos científicos pertinentes y aumento de investigación para su mejoramiento continuo. El conocimiento científico debe promoverse en todos los escenarios de la sociedad y evitar que quede atrapado en el circuito de los científicos. Se propone fortalecer especialmente la interacción de divulgadores científicos con decisores en políticas públicas y forestales.

Foundational shrub species can support vertebrate communities within desert ecosystems. These shrubs provide thermal refuge to aid in temperature amelioration and to escape predation. Within Southern California, USA, harsh abiotic conditions influence the frequency of these shrub-animal interactions. We tested the hypothesis that increasing shrub density will positively influence local vertebrate communities across a variety of arid ecosystems within Southern California. We used a combination of camera trapping and temperature pendants across a 2-year field study to assess the effects of shrub density and near-surface air temperature on vertebrate community composition. Sites were established across Southern California, each consisting of four 20 m radius microsites, with shrub densities ranging from 0 to 14 individuals. Increasing shrub densities significantly increased the frequency of observation and richness of local vertebrate communities. Relatively higher near-surface air temperatures (NSAT) significantly decreased vertebrate observations, richness, and evenness. Sites with relatively higher annual aridity negatively influenced vertebrate species observations and richness, but could be offset by increasing shrub densities. While shrub encroachment in many ecosystems may have negative impacts on species biodiversity, our findings suggest that increasing densities of foundational shrub species positively influences vertebrate community measurements and composition across varying arid ecosystems. Understanding how these foundational shrub species can be used to assess vertebrate communities can provide key insight into vertebrate-shrub interactions and how these densities can shape the biodiversity of an ecosystem.

DesertNet () is an interdisciplinary scientific network which was established in October 2006 at the UN premises in Bonn, Germany, by a group of international scientists. The network strives to generate and enhance scientific knowledge and understanding of the biophysical and socio-economic processes of desertification. This international scientific network provides an international platform for scientifically based discussions and exchange of ideas, addressing knowledge gaps, and identifying research areas. DesertNet is also a think tank community which identifies issues and priorities for the sustainable development of drylands. The paper outlines the current role of DesertNet in the international scientific community and it delineates its role to strengthen the Science/Policy Interface.

El presente trabajo aborda la influencia de la producción animal en el cambio climático desde una perspectiva multidisciplinaria. En las últimas décadas, el aumento de emisiones de gases de efecto invernadero, la degradación de suelos y la sobreexplotación de recursos han puesto en crisis la capacidad de carga de los ecosistemas, afectando gravemente la biodiversidad y el bienestar humano. Organismos internacionales como la FAO, el IPCC y el SNCC han señalado que la producción pecuaria no solo altera la dinámica atmosférica, sino también el ciclo del agua, la regeneración de suelos y la cobertura vegetal, siendo uno de los sectores con mayor impacto ambiental a nivel mundial. Ante la creciente demanda de productos de origen animal, impulsada por el crecimiento demográfico y la urbanización, esta investigación examina la magnitud del problema en tres capítulos: primero, una descripción del cambio climático y sus causas; segundo, un análisis comparativo del impacto de las principales industrias de crianza; y tercero, la presentación de alternativas y propuestas sustentables que permitan mitigar los efectos ambientales de esta actividad.

La investigación aplica un enfoque transdisciplinario para diagnosticar la degradación de la fertilidad en suelos aluviales drenados para cultivos de banano en Urabá, Antioquia. El problema radica en la ausencia de control sobre esta degradación, lo que reduce rendimientos sin claridad sobre si es causada por factores químicos, físicos o de manejo agrícola. El análisis integral propuesto incluye: uso del suelo y programas de nutrición; cantidad y calidad del agua y su efecto en salinización; distribución espacial de nutrientes según muestreos y escalas cartográficas; y propiedades físicas del suelo como retención de humedad y compactación. Se plantea que un diagnóstico efectivo debe considerar simultáneamente composición química, características físicas, disponibilidad y calidad de agua, así como prácticas de fertilización, para comprender y mitigar el deterioro de la fertilidad y optimizar la producción bananera en la región.

Mycorrhizal fungi are an essential component to consider for better management of soil fertility, particularly in degraded rangelands of drylands. The present article presents a field survey of colonization and intensity of arbuscular mycorrhizal fungi (AMF) on prickly pear (Opuntia ficus-indica) roots from young (5 years old) and old (more than 20 years) plantations. The results observed were explained by seasonality and edaphic factors. Prickly pear roots showed a mycorrhizal frequency (F%) up to 100% of colonization and a mycorrhizal intensity (M%) that may exceed 70%. According to ANOVAs, both F% and M% varied significantly between Prickly pear plantation ages, but only M% between seasons. The Generalized linear model showed that edaphic factors have no effect on the variation of F%. However the statistical model showed that M% were significantly influenced by active CaCO 3 , organic matter, carbon, nitrogen, phosphorus contents and C/N. Our findings highlight the importance of mycorrhization in rehabilitation programs of degraded rangelands by prickly pear plantations in semiarid and arid lands, particularly during early plant ages and under environmental abiotic stresses such as climate and soil type.

The sensitivity map to desertification of Eastern Algeria (Aures region) has been elaborated by the crossing of four thematic layers (vegetation, climate, soil and the socioeconomic states), which have the main impact on the evolutionary process of desertification. The followed methodology is inspired from the desertification model MEDALUS (Mediterranean Desertification And Land Use), which use qualitative index to define the land zones sensitive to desertification. Cartographical information of vegetation, climate variation, soil and the socioeconomic states obtained from cartographic data were transformed to numerical data then seized on, structured and managed by an algorithm dedicated to a geographical information system. Moreover, ALSAT-1 satellite images, geologic and soil maps were used as main sources for calculating the index of Environmental Sensitivity Areas (ESAI) for desertification. Besides, the main goal of this study is to identify places with different sensitivity to land degradation in Aures region (East Algeria) by means of a modeling approach developed in the European Commission funded MEDALUS project, which identifies such areas on the basis of an index (ESA index, Environmental Sensitive Area index) in which environmental quality (climate, vegetation, soil) as well as anthropogenic factors (management) are included as weighted layers.

Using GIS and remote sensing tools, the current dissertation shows the impact of agricultural mutation in drylands and highlights the effect of date palm (Phoenix dactylifera) plantations (DPP) on desertification phenomenon in oases of the Algerian Sahara Desert. The spatiotemporal survey was conducted using three Landsat satellite images (TM-1984, ETM+-1999, and OLI-2013). Likelihood supervised classification was used to quantify DPP change over three decades, whereas four remote sensed indices were extracted as indicators of desertification process in the study area: Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI), Salinity Index (SI-T), and Crust Index (CI). Generalized linear mixed models (GLMMs) were applied to test the effects of year and DPP 'presence/absence' for NDVI; year, DPP and NDVI for both CI and NDMI; year, DPP, NDVI and NDMI for SI-T. DPP area and tree numbers quadrupled over the last three decades with a surface increase of 4822 ha and more than 0.5 million trees. DPP presence positively influenced NDVI, NDMI and CI, but negatively affected SI-T. Highly significant positive relationships were found between NDVI-DPP, NDVI-NDMI, and NDVI-CI, although negative relationships were obtained between SI-T-NDVI and SI-T-NDMI. DPP areas indicated higher NDVI, NDMI and CI values, but with lower SI-T values compared to the rest of the desert habitats. Our results highlighted the potential role of DPP in controlling and mitigating desertification in hot drylands. This arises from the effectiveness of strategic agricultural policy programs. Landsat series data provided a cost-efficient tool for monitoring change in oases and arid environments.

Various natural and anthropogenic activities such as climate change, urbanization and industrialization play a vital role in changing the land characteristics. These changes does not only affect the human lives and activities, but also results in tremendous decrease in agricultural productivity and arable land. Thus, the purpose of this study is to analyze the land degradation and desertification in Pakistan using satellite imageries data acquired from the Landsat 8 and 9. For the empirical analysis, various indices such as Normalized Difference Vegetation Index, Normalized Difference Bare Soil Index, Supervised classification and Land Surface Temperature are examined using Google earth engine cloud computing platform. The results showed that desertified and built-up-land are increasing, while degraded land, arable land, and vegetative land are decreasing in the study area. Also, results of land surface temperature analysis showed a rise in the temperature up to 3.06 0 C as compared to previous two years. Moreover, estimated findings from regression analysis showed that Normalized Difference Vegetation Index, and Normalized Difference Bare Soil Index positively affects the Land Surface Temperature. The findings of study are important for government and concern stakeholders to take necessary measures to stop the conversion of productive green land into unproductive degraded and desertified land.

The abandonment of land is a global problem with environmental and socioeconomic implications. An approach to assess the relationship between land abandonment and a large set of indicators was illustrated in the present study by using data collected in the framework of the European Union DESIRE research project from 808 field sites located in 10 study sites in the Mediterranean region, Eastern Europe, Latin America, Africa and Asia. A total of 48 indicators provided information for biophysical conditions and socioeconomic characteristics measured at the plot level. The selected indicators refer to farm characteristics (family status, land tenure, present and previous types of land-use, soil depth, slope gradient, tillage operations) and to site-specific characteristics including annual rainfall, rainfall seasonality and water availability. Classes were designated for each indicator and a sensitivity score was assigned to each class based on existing research or empirically assessing the importance of each indicator to the land abandonment issue. Questionnaires for each process of land degradation were prepared and data were collected at field site level in collaboration with land users. Based on correlation statistics and multivariate analyses more than ten indicators out of 48 resulted as significant in affecting land abandonment in the studied field sites. Among them, the most important were rainfall seasonality, elderly index, land fragmentation, farm size, selected soil properties, and the level of policy implementation. Results contribute to the development of appropriate tools for assessing the effectiveness of land management practices for contrasting land abandonment.

There is often confusion among several terms when people discuss ecological and environmental issues. Terms that cover many important ecological or environmental concepts are frequently grouped or defined too broadly, causing them to lose their significance, or too narrowly, leading to misinterpretations. This is especially true with laypeople's terms, but even scientists often use such words without providing clear definitions.

O uso desenfreado dos recursos naturais tem como reflexo um elevado grau de degradação do ambiente causando prejuízo na dinâmica natural do ecossistema. Neste contexto, o presente estudo objetivou verificar o potencial de uso de técnicas nucleadoras em área degradada da Fazenda Cachoeira de São Porfírio, município de Várzea, semiárido do Estado da Paraíba. Foram utilizados poleiros artificiais secos e enleiramento de galharias visando a formação de núcleos de atração a fauna dispersora de propágulos. O experimento foi avaliado por 12 meses. Os poleiros foram utilizados por aves durante o período experimental, incrementando a chuva de sementes da área. O enleiramento de galharia, que simula abrigos artificiais para a fauna e microrganismos, atuam na decomposição desse material. Verificou-se decomposição do material formador das leiras com diminuição do volume original e adição de matéria orgânica ao solo. Foram contabilizadas 125 sementes, principalmente de Jatropha curcas L. (pinhão manso) e Cnidosculus queercifolius Pohl (faveleira), nos coletores colocados sob os poleiros, o que indica presença de aves no local do experimento. Portanto, tais técnicas nucleadoras atuaram no incremento na chuva de sementes e aumento de conteúdo da matéria orgânica no solo e, utilizadas em conjunto, favoreceram a sucessão natural e a reintrodução de plantas e animais na área degradada. Palavras-chave: degradação ambiental, caatinga, dispersão de sementes.

Public Libraries in the United Arab Emirates are recognized as repositories of human knowledge and heritage especially in today’s knowledge-driven economy where knowledge and innovation are essential drivers of growth and prosperity. Public Libraries provide access to information which may be used for self-development, cultural awareness and enhancement and continuing education. For children and young people they provide a positive alternative to pastime reading, researching and participating in activities organized by the library. United Arab Emirates is a union of seven emirates and public libraries in these emirates are affiliated mainly to the Ministry of Culture, Youth and Community Development (MCYCD), and libraries set up by local entities. The National Library in Abu Dhabi also serves as a public library and has recently embarked on projects of establishing branch libraries in different locations in the emirate. Most of the libraries have been established as joint ventures b...

Os modelos tradicionais de recuperacao de areas degradadas nao abrangem as fases iniciais de sucessao ecologica, esta por sua vez e caracterizada pela colonizacao por ervas, lianas arbustos e arvoretas e deste modo desconsidera as interacoes planta/animal o que impede a sucessao natural. O uso de tecnicas como poleiros artificiais para atracao da avifauna frugivora pode contribuir substancialmente para este processo. Objetivou-se comeste trabalho avaliar a eficiencia dos poleiros secos como intensificadores das chuvas de sementes em uma area de recuperacao ambiental. O presente estudo foi realizado em uma area de 2,21 ha, na cabeceira do Corrego das Clemencias, na area urbana de Quirinopolis – GO. Foram instalados seis poleiros secos (2,5 m) e seis coletores de sementes (1 x 1 m).Durante os seis meses foram coleta dos insetos, diasporos e fezes de aves encontradas nos coletores. Foi coletado um total de 03 insetos, 456 sementes e 114 fezes.As sementes foram distribuidas em 3 morfoes...

In dry and geologically ancient hinterland beyond Geraldton, Western Australia, lies much of the imaginative terrain for Randolph Stow's oeuvre and in particular his seminal and deeply wrought novel Tourmaline. Beyond the edge of the Wheatbelt lie the old crumbling former goldrush towns of the Murchison, clinging on precariously to survival on the Yilgarn plateau. This essay draws out connections between the novel Tourmaline and the townships, places and spaces which inspired it. This essay draws upon what could be termed locative criticism - travelling to and engaging with the physical places - while also publishing for the first time a series of slides Stow kept in a box labelled 'Tourmaline' and referred to finish the novel while overseas.

Open dumpsites are common features in cities in developing countries of the world, Nigeria inclusive. The wastes disposed of in these dumpsites can cause a number of public and environmental health risks including surface and groundwater pollution. The objectives of this research are to examine the causes and challenges facing the disposal and management of municipal solid waste (MSW) in major cities in Nigeria, with a view to proffering sanitary or scientific-based solutions to this problem. The method adopted was in-site observation of notorious dumpsites in the study area, interview with stakeholders, discussion with residents around the dumpsites and review of relevant literatures. The result of the investigation shows that unguided disposal and management of municipal solid waste are basically associated with lack of public awareness programmes, limitation in access to effective policies and enforcement on the part of the people and the government respectively, lack of qualified waste workers, poor funding, lack of biological and mechanical waste treatment plants/facilities, and non-usage of non-governmental organizations (NGOs) Schemes and community-based approaches in tackling the problem in an holistic manner. The study suggests new approaches that could be used to achieve sustainable and effective waste disposal and management which would support government's effort in improving solid waste management in Nigeria.

Se compararon dos métodos (combustión húmeda y calcinación a 550 ºC) para la determinación de la materia orgánica en materiales orgánicos. En el ensayo participaron nueve laboratorios, empleando cinco materiales orgánicos (tres composts y dos sustratos), analizados por cuadruplicado. La precisión se evaluó calculando la repetibilidad y la reproducibilidad, según la norma COVENIN 2972-92 (ISO 5725-86). No se encontraron diferencias significativas entre métodos, laboratorios, ni réplicas, por lo que se asume que los métodos comparados generan resultados estadísticamente iguales. La precisión evaluada a través de la repetibilidad y la reproducibilidad no resultó dependiente del nivel de materia orgánica. Los menores valores de repetibilidad y reproducibilidad obtenidos con el método de calcinación indican que esta modalidad analítica es más precisa. Se recomienda la aplicación del método de calcinación porque se basa en un procedimiento rápido, sencillo, no consume reactivos químicos y...

Understanding what led to desertification in the long-term is crucial for adaptation to climate change and pressures on resources in North Africa, but existing maps do not accurately show the extent of degraded land or the traditional water systems which underpinned cultivation. These products rely on recent vegetation trends and hindcasted statistical data. Desertification which occurred prior to the later twentieth century is poorly represented, if at all. However, large areas of abandoned fields are distinctive in satellite imagery as brightly reflectant and smooth surfaces. We present a new and opensource machine-learning workflow for detecting desertification using satellite data. We used Google Earth Engine and the random forest algorithm to classify five landcover categories including a class representing desertified fields. The input datasets comprised training polygons, a 12-band Sentinel-2 composite and derived tasselled cap components, and a Sentinel-1 VV-polarisation composite. We test our approach for a case study of Skoura oasis in southern Morocco with a resulting accuracy of 74-76% for the desertification class. We used image interpretation and archaeological survey to map the traditional irrigation systems which supply the oasis.

Perception of soil's history is an essential in addressing the imperious issues related to the sustainable agricultural development and land degradation in the hyper arid and arid regions. Therefore, the current work was undertaken to appraise of pedogenesis and parent material uniformity using Computer Controlled Scanning Electron Microscopy (CCSEM) technique. Five soil profiles (P1, P2, P3, P4, and P5) were selected for study on a topo-sequence model representing most of ground elevations of some soils adjacent to Bani Mazar-El Boiety road at western hyper arid desert of El Minia, Egypt (30 о 15`40" to 30 о 28`58"E and 28 о 31`40" to 28 о 33`00"N 100 to 170 m A.S.L.;54 km 2 ). The data of CCSEM showed that the weighted means (%) correlated to the ground elevation of Opaque minerals varied between 30.18 at (150-160 m; P4) and 43.81 at (140-150 m; P2) while Pyroboles diverged between 40.85 at (150-160 m; P4) and 92.80 at (140-150 m; P5), Zircon (Z) ranged between 0.85 at (140-150 m; P2) and 15.79 at (160-170 m; P3), Rutile (R) values were 2.14 at (160-170 m; P3) and 30.09 at (150-160 m; P4), contents of Tourmaline (T) were 0.72 at (110-120 m; P1) and 6.51 at (150-160 m; P4), Garnet varied between 0.17 at (160-170 m; P3) and 0.86 at (140-150 m; P2) within the studied soils, reflecting the heavy mineral suite was influenced by topo-sequence of the research area also indicating the study soils are recently formed, weakly developed, and have low effect of pedogenic processes. Irregular vertical distribution with depth of Z/T, Z/R, Z/R+T ratios, and index figure proved that soil parent materials were stratified in nature and apparently formed of multi-depositional regimes. Scanning electron micrographs also confirmed that the investigated soils most probably transported and originated by water agent to distances not far away. The same conclusions have been indicated by applying the grain size analysis of sand fraction reported by .

This paper examines the factors influencing landuse conversion in Ibadan Municipality, Nigeria with a view to providing information that could inform policy on landuse planning. Primary and secondary data source were adopted for the study. The study adopted systematic sampling technique in the selection of 531 buildings (5%) of the existing 10,620 buildings in the study area. Data were analysed using factor analysis and multiple regression analysis. Six factors were identified as the major factors influencing landuse conversion in the study area, these include physical, environmental, economic, institutional, social and cultural factors. The study further revealed that among the six factors, economic factor has the highest influence on landuse conversion in Ibadan Municipality. Majority of decisions on landuse conversion were made for economic purpose; starting from on-street trading to the legalized economic activities. All the factors were statistically significant except institutional factors. This study concluded that landuse conversion in Ibadan Municipality is at alarming rate and tending to succession of residential landuse by other landuses (most especially commercial landuse).

This study is devoted to Nador massif located in the steppe environment of Tiaret region in the west of Algeria. This massif is characterized by a diversity of flora composed of 121 taxa belonging to 38 families and 98 genera. Biological spectrum indicates a predominance of therophytes (38%) and chamaephytes (19%), geophytes (14%). The most important families are Poaceae and Asteraceae. Mediterranean element is relatively dominant (55%) according to chorologic plane. Shannon-Weaver e diversity index is relatively high (4.55) indicating a richly diverse site. Disturbance index (63.6%) reflects highly significant degree of massif vegetation disturbance, which also reflects a more open environment. To better understand the structure of vegetation using the classification is imperative

Introducción. Las actividades agropecuarias y las anomalías atmosféricas representan un alto porcentaje de alteraciones en ecosistemas riparios, modificando rápidamente servicios ecosistémicos, como la pérdida de la calidad del entorno. Esta investigación midió el efecto de variaciones climáticas sobre el uso del suelo agropecuarios asociados a la zona riparia. Métodos. Con imágenes Lansat 8 y el preprocesamiento de estas en SAGA GIS, se realizó la extracción de datos del Índice de Diferencia de Vegetación Normalizada (NDVI, por sus siglas en inglés) por mes durante el 2022. Se procedió a realizar análisis estadísticos en RStudio para test Kruskal Wallis (KW). Dentro del método se analizaron los tipos de correlaciones existentes entre los datos atmosféricos y los NDVI. Resultados. La dispersión de los datos en usos de suelo y vegetación adyacente (Va) presentaron valores similares a lo largo del año, considerando que esta última (Va) mostraron valores asociados a vegetación media. D...

CERTIFICO :' ~ Que la memoria adjunta, titulada " Aplicación a suelos calizos de fertilizantes fosforados en,combinación con ácidos húmicos", presentada por Dña. Antonia Cuesta Rangel, para aspirar al Grado, de Doctor en Ciencias Químicas, ha sido realizada en este Departamento bajo la dirección de los Drs . Sánchez Andréu y Juárez Sanz. El presente ejemplar ha sido revisado -por el profesor que certifica . La materia orgánica del suelo, aunque pisoteada y menospreciada, 'regula en gran medida la nutrición de la humanidad . Su origen son los restos vegetales, excrementos y cadáveres de animales . Dichos residuos son atacados, transportados y descompuestos por la mesofauna del suelo. Dentro de la complejidad de la materia orgánica, encontramos elementos constituyentes o excretados por los microorganismos del suelo y aparecer) además unas sustancias orgánicas difícilmente ~clasificables, de color oscuro,, muy resistentes al ataque' microbiano que, por ofrecer propiedades comunes, se engloban bajo la denominación genérica de sustancias húmicas del suelo, o, 'simplemente humus . Estas suelen representar del 60 al 90% dé la materia orgánica total del suelo, por Io que, unido a su 'bioestabilidad, no sólo interesan desde un punto de vista cuantitativo, sirio también por su permanencia en el suelo . Según, Gallardo (1980), la materia orgánica del suelo mejora no sólo la asimilabilidad,de ,los nutrierttes,poco solubles'( P, Mn) sino que también suministra adecuadamente oligoelemeritos (Zn, Cu, Fe, etc. .) a la planta . Continúa diciendo que los fenómenos de antagonismo entre elementos nutritivos ~ebundantes, como el calcio, y los minoritarios como el magnesio, hierro, etc., se ven disminuídos gracias a la materia orgánica . El fósforo, un nutriente esencial para los vegetales y generalmente deficitario, se debe adicionar a los cultivos' a fin de asegurar 'buenos rendimientos y calidad en las cosechas. El hecho de que el fósforo no se encuentre siempre disponible para la planta se debe, en parte, al control que ejercen las reacciones de adsorción del P en el suelo sobre la disponibilidad de P para la planta (Syers y Mackay, 1986) . En suelos calizos, como es nuestro caso, el P es retenido frecuentemente por calcita dando lugar a la formación de fosfato cálcico amorfo, que gradualmente pasará a una estructura más cristalina . Aplicación a suelos calizos de fertilizantes fosforados en compunción con ácidos húmicos.

Se estudió la influencia de Bulnesia retama sobre la velocidad de infiltración en un sitio piloto de la cuenca del Bermejo (San Juan). La infiltración está relacionada con el escurrimiento su perficial y es afectada por la textura y estructura del suelo, el contenido de materia orgánica, la humedad inicial y la cobertura vegetal. Los datos de campo fueron tomados por unidades homogéneas definidas sobre la base del procesamiento digital de un modelo de elevación, ma peo participativo e interpretación visual de una imagen satelital. Se realizaron cinco transectas lineales de 50 m, midiendo cobertura con la técnica de intersección por línea. Los ensayos de infiltración fueron realizados dentro y fuera de la canopia, con infiltrómetro de anillo simple (21 cm de diámetro) y carga variable. Los datos se ajustaron en función del diámetro del infil trómetro. Se tomaron muestras de suelo determinando: contenido de materia orgánica, textura, nitrógeno total, conductividad y pH. La cobertura p...

Il presente lavoro svolto all'interno del progetto di ricerca Bioforme (finanziato dal Ministero delle Politiche Agricole Alimentari e Forestali) e poi ampliato, si è posto come obbiettivo la creazione di un GIS per la stima dell'area suscettibile alla coltura di Hedysarum coronarium, da impiegare insieme ad alghe, allo scopo coltivate, nella produzione di biodiesel di terza generazione.

The Strategy seeks to enhance understanding of emerging underlying drivers of change on our continent and sets out to address them in an integrated, inclusive and holistic way in order to build more transformative and sustainable community resilience to the considerable stresses and uncertainties that we face as a continent today.

Current climate change and precipitation and temperature anomalies in Northern China and Mongolia were plotted and compared to vegetation indices (MODIS/Terra Vegetation Indices Monthly L3 Global 0.05Deg CMG V006; last accessed 07th of April 2021; ) (CRU, Harris and Jones, 2019, Harris).

La stima dell'ETP in tre importanti comprensori irrigui della Sardegna: meridionale (39° 17' lal. Nord), centrale (39°53' lal. Nord) e settentrionale (40°41' lal. Nord) mediante ricorso alle metodiche evapotraspirative di fonte F.A.O. indica la notevole sovrasti ma derivante dall'utilizzo della Blaney-Criddle originale, differenze che si riducono passando all'equazione di Penman (originale e F.A.O.), della radiazione solare e della B.-C. F.A.O .. Quest'ultima metodica, ritenuta la più idonea sulla base di primi rilievi lisimetrici, valuta l'ETP media annua pari a 1194 mm, 1077 mm e 1022 mm rispettivamente per la Sardegna meridionale, centrale e settentrionale. La successiva analisi delle piogge utili evidenzia che esse sono pari al 50% delle totali (nel caso del prato di graminacee) e che coprono l'ETP per circa il 22%. Pertanto il deficit irriguo stagionale, calcolato con l'introduzione dei coefficienti colturali di fonte F.A.O., è compreso tra gli 841 mm, 791 mm e 706 mm del prato e i 353 mm, 322 mm e 311 mm dell'olivo rispettivamente nella Sadegna meridionale, centrale e settentrionale. SUMMARY ETP calculation for three important irriguous areas of Southern (39°17' N. I), Centrai (39°53' N. I) and Northern (40°41' N. I) Sardinia through F.A.O. method shows too much high values with originai Blaney-Criddle equation, reduced differences with Penman (originai and F.A.O.) equation, Radiation method and B.-C. F.A.O. equation respectively. The last method, believed the most suitable according to the first lisimetric measurements, estimates annual mean ETP equal to 1194 mm, 1077 mm and 1022 mm for Southern, Centrai and Northern Sardinia. Effective rainfall successive analysis shows they are 50% of total rainfall (in case of grasses) and they hold ETP for about 22%. Therefore seasonal irrigation requirements, calculated through F.A.O. crop coefficients, are among 841 mm, 791 mm and 706 mm concerning grasses, and 353 mm, 322 mm and 311 mm concerning olive tree, for Southern, Centrai and Northern Sardinia. Professore Associato e Tecnico Laureato presso l'Istituto di Coltivazioni arboree. Borsista dell'Assessorato per l'Agricoltura e la Riforma Agro-Pastorale della Regione Sardegna . ••• Collaboratore tecnico presso l'Istituto di Arboricoltura Mediterranea del C.N.R. I diversi Autori hanno contribuito in egual misura alla ricerca.

La partecipazione del Servizio IdroMeteorologico di ARPA Emilia-Romagna al progetto SEDEMED ha riguardato, tra l'altro, lo sviluppo di un strumento evoluto per il monitoraggio dei fenomeni siccitosi e per la guida della pianificazione delle risorse idriche in agricoltura. Il nucleo dell'attività ha riguardato l'implementazione del modello di bilancio idrico territoriale CRITERIA, attraverso: l'individuazione di un'area pilota vulnerabile ai fenomeni siccitosi, ove applicare il modello di bilancio idrico; l'acquisizione della strumentazione di campo per la taratura dei risultati del modello di bilancio idrico e la costituzione di una banca dati per l'alimentazione del modello e la verifica dei risultati; lo sviluppo di un laboratorio di telerilevamento per l'aggiornamento delle basi dati utili ai modelli di bilancio idrico; l'arricchimento delle routine di calcolo e delle matrici informative del modello di bilancio idrico territoriale CRITERIA, anche attraverso la definizione di un nuovo indice di siccità agricola. modo molto semplificato, mette in relazione la precipitazione con l'evapotraspirazione potenziale. Per un insieme di punti di rilevamento della precipitazione, nei quali erano disponibili serie storiche di dati mensili di almeno quaranta anni, è stato calcolato l'indice SPI per valori a 3, 6, 12, 24 mesi. Considerando l'inerzia del sistema pianta-suolo l'attenzione è stata focalizzata sul valore dell'SPI a 24 mesi, valutandone la tendenza nelle diverse aree della regione. Dalla figura 1 si osserva una tendenza negativa su quasi tutta la regione ad esclusione della sola fascia sud-orientale dove, al contrario, si denota una qualche tendenza alla crescita dell'indice. L'indice risulta diminuire con maggiore evidenza sulle aree centrali ed appenniniche della regione, con valori massimi del trend dell'ordine di -0.0035 unità SPI/anno nell'Appennino e nella pianure bolognesi e ravennati. Più in particolare, dall'esame dell'indice SPI medio regionale a 24 mesi, appaiono un certo numero di eventi siccitosi di diverso rilievo (evidenziati in figura 2) la cui durata ed intensità appare in aumento negli ultimi venti anni.

La steppe algérienne s’étale sur 27 millions d'hectares, d’où le pâturage est l'activité principale avec 18 millions de têtes. Le problème de ces régions réside dans la fragilité de milieu naturel exposé à un climat sec, ce qui provoque la dégradation des sols et des parcours. Par conséquent, il est nécessaire de lancer une étude approfondie dans le but d’illustrée les variations dynamiques de la végétation steppique. Cependant, la wilaya de Laghouat, appartenant à cette zone pastorale, occupent 2.505.200 hectares dont 91 % sont dégradés ; et pour mettre en évidence cette situation, il est important d’adopter les méthodes d’étude pour couvrir la plupart de la région par : (1) l’analyse du climatiques (1934-2013) montre le décalage du régime saisonnier des précipitation, et l’ augmentation de la température ; (2) l’analyse socioéconomiques (1985-2013) indique la sur exploitation accentuée des ressources naturels. Un état confirmé par (3) l’analyser géomatiques et les techniques de télédétection, qui permettent l'étude de l'ensemble du la région, depuis 1972 à 2013. A fin de comprendre, et prévenir, l’amplification de la dynamique de dégradation végétale, situation inquiétante, nécessitant l’intervention pour réduire l’effet de désertification, réanimer et préserver les écosystèmes steppiques.

Land degradation menaces the livelihoods of millions of people living in drylands of the world.
Desertification, land degradation, and drought caused by human activities and climatic variations are having
a huge toll on human well-being and the environment, ranking among the greatest development challenges
of our time.  Like most sub-Saharan African countries, Somalia suffers from environmental degradation
and desertification. The country suffers from both natural and man-made environmental issues. High levels
of deforestation and overgrazing cause desertification and soil erosion. The country has a rapidly growing
population whose lives depend on natural resources for their pastoralist and agricultural livelihoods. Land
degradation adversely affects the productivity of pastoralism and agriculture and undermines the fight
against poverty and hunger. Land degradation threatens the medium- to the long-term sustainability of
pastoral systems since degraded rangelands cannot support the feeding requirements of animal populations.
There is very low rainfall and evaporation is extremely high. Recurrent terrible droughts followed by river
and flash floods also contribute to environmental degradation threatening the population living in the
country in the future. 
The United Nations Convention to Combat Desertification (UNCCD) facilitates international efforts to
combat desertification, mitigate the effects of drought, and alleviate poverty. Somalia has been a signatory
to the UNCCD since 2002 and has formulated this National Adaptation Plan (NAP) to fulfill its first
obligation under the Convention., which addresses combating desertification and land degradation issues.
The country also submitted its first reporting process under the UNCCD (2018).  Following the
Convention's relevant decisions, the Federal Government of Somalia (FGS) is determined to undertake a
series of actions to demonstrate its commitment to present its report on combating desertification. 
This report present is the Somalia National UNCCD Report 2021-2022 on the five (5) UNCCD Strategic
Framework 2018-2030. The report is prepared by the Federal Ministry of Environment and Climate change-
the focal point of the Convention. The report is part of an initiative to enhance national-level technical and
institutional capacity for reporting and Land Degradation Neutrality (LDN) monitoring in the context of
the UNCCD Strategic Framework 2018-2030 and Sustainable Development Goal (SDG15.3). This report
represents the commitment of Somalia to the UNCCD to employ its greatest efforts in combating
desertification. The report reflects the most ambitious and continuous efforts by the Federal Government
of Somalia to combat desertification. This report is aligned with the below-stated five strategic objectives
(SO), which guide the actions of all UNCCD stakeholders and partners from 2018–2030.

La agricultura sostenible se ha convertido en un eje fundamental para garantizar la seguridad alimentaria mundial, especialmente en un contexto donde el cambio climático y la degradación de los recursos naturales amenazan la productividad agrícola. La adopción de prácticas agrícolas sostenibles está directamente alineada con los Objetivos de Desarrollo Sostenible (ODS) establecidos por las Naciones Unidas, los cuales buscan erradicar el hambre, garantizar la sostenibilidad de los ecosistemas y mitigar los efectos del cambio climático (FAO, 2017). Entre las prácticas agrícolas que contribuyen a estos objetivos, el uso de cultivos de cobertura ha demostrado ser una estrategia efectiva para mejorar la salud del suelo y aumentar la productividad de las hortalizas. En este contexto, la pangola (Digitaria eriantha) se posiciona como una opción viable para ser utilizada como cultivo de cobertura en la producción de hortalizas.