The document discusses the close link between humans and soil. It notes that the name "Adam" comes from the Hebrew word "Adamiss" meaning earth or soil, and his life and livelihood derive from the soil. It also notes that Eve's name, "Hava", literally means life. Together Adam and Eve signify "Soil and Life," highlighting the inextricable relationship between humans and the land.

1. MANEJO de SUELOS y FERTILIDAD Objetivos generales de la materia : Que el alumno comprenda la necesidad de planificar el uso y manejo de los suelos de acuerdo a sus potenciales productivos , para poder prevenir y/o corregir procesos degradatorios con el fin de obtener la máxima eficiencia a través de una producción sostenible

2. S U E L O RECURSO NATURAL NO RENOVABLE, PARTE DEL “CICLO DE LA VIDA” EN LA TIERRA.

3. Basic Soil Plant Relationships Mineral Organic Water Air 45% ~5% 50% MATERIAL SÓLIDO (50%) POROUS MEDIA (50%)

4. S U E L O planta Alimento + O 2 H 2 O + CO 2 microorganismos CONCLUSIONES: La vida depende del suelo El suelo...”vive y respira” Los microorganismos son los “ciudadanos” del suelo  Mantienen la interfase activa

5. LA AGRICULTURA.... siempre modifica el funcionamiento natural del suelo: Alteración de los biociclos de los nutrientes Menor retorno de materia orgánica Contínuos stress físicos (x el laboreo) AGRICULTURA SOSTENIBLE: conservar materia orgánica Menor erosión Usar recursos degradables BALANCE PRODUCCIÓN/CONTAMINACIÓN

6. PRINCIPALES FUNCIONES DEL SUELO REGULADOR de procesos bióticos (biodiversidad) REGULADOR ciclos y flujos de sustancias y Energía ... Después de numerosos estados retornarán al suelo “ POROUS MEDIA” regula ciclo de agua y el balance calórico REDISTRIBUCIÓN del agua: precipitación ----- infiltración / escorrentía PROTECTOR de la litósfera.

7. F E R T I L I D A D CAPACIDAD DE PRODUCCIÓN DEL SUELO ( proporcionar a los vegetales los nutrientes para un desarrollo equilibrado) QUE PARA MANIFESTARSE NECESITA LA CONTRIBUCIÓN DE OTROS FACTORES: - físicos / - químicos / -biológicos - fisicoquímicos / - bioquímicos

8. F E R T I L I D A D EDÁFICA (1) CAPACIDAD DEL SUELO PARA SOSTENER Y NUTRIR A LAS PLANTAS ECOLÓGICA (2) Constituída por los FACTORES EDÁFICOS + EXTRAEDÁFICOS(*) (extrínsecos) (*) Clima/potencial genético/características del cultivo/acción antrópica, etc...

9. PRODUCTIVIDAD FACTORES EDÁFICOS + FACT. EXTRAEDÁFICOS CAPACIDAD DE PRODUCCIÓN POR SUPERFICIE CULTIVADA

10. SOSTENIBILIDAD CAPACIDAD O HABILIDAD DE SOSTENER PROCESOS EN FORMA CONTÍNUA, EVITANDO SU DECAIMIENTO AGRICULTURA SOSTENIBLE Cuando se manejan exitosamente los recursos para satisfacer las necesidades cambiantes de la sociedad, conservar los recursos naturales y en algunos casos, mantener y/o mejorar el medio ambiente

11. Clasificaciones de la FERTILIDAD EDÁFICA Por su ORIGEN o EVOLUCIÓN Por su ASPECTO DINÁMICO

12. ORIGEN o EVOLUCIÓN NATURAL Sobre ella sólo actúan las condiciones de la naturaleza (p.e.: suelos vírgenes) ADQUIRIDA modificada según el manejo, pudiendo ser mayor o menor que la F. Natural (p.e.: suelos cultivados)

13. su ASPECTO DINÁMICO F. ACTUAL (Factor INTENSIDAD) La que el suelo posee en un momento dado o que está en condiciones de manifestarse de inmediato F. POTENCIAL (factor CAPACIDAD) Recursos que el suelo tiene para el futuro: se irán haciendo disponibles en 10, 15, 20 ... años

14. 1. Nutrición vegetal??? Tomar los elementos minerales desde el suelo No se refiere específicamente a la fotosíntesis.

15. Elementos químicos requeridos por las plantas Esencialmente requieren 13 elementos minerales para su crecimiento Estos elementos son necesarios para completar su ciclo y por ello los denominamos nutrientes vegetales esenciales Cada uno tendrá una función crítica, y será requerido en cantidades variables. Estos nutrientes difieren en la forma en que son absorbidos por la planta, por sus funciones en la planta, por su mobilidad en el vegetal (y dentro del suelo) y por los síntomas de deficiencias o toxicidades característicos para cada uno de ellos.

16. Nombre % en planta relativo a N Funciones Macronutrientes (primarios) Nitrogen N 100 Proteins, amino acids Phosphorus P 6 Nucleic acids, ATP Potassium K 25 Catalyst, ion transport Mesonutrientes ( secundarios) Calcium Ca 12.5 Cell wall component Magnesium Mg 8 Part of chlorophyll Sulfur S 3 Amino acids Iron Fe 0.2 Chlorophyll synthesis Micronutrients (oligoelementos) Copper Cu 0.01 Component of enzymes Manganese Mn 0.1 Activates enzymes Zinc Zn 0.03 Activates enzymes Boron B 0.2 Cell wall component Molybdenum Mo 0.0001 Involved in N fixation Chlorine Cl 0.3 Photosynthesis reactions

17. 3. Absorción de los minerales desde el suelo Dominant in mineral soils: Dominant in organic soils: A. Bulk flow: Uptake in the transpiration stream B. Mycorrhizae: symbiotic relationship with fungi Nutrients diffuse to regions of low concentration and roots grow into and proliferate in soil zones with high nutrient concentrations (horse manure in sand). Roots are slow growing but mycorrhizal fungi proliferate and ramify through the soil. Symbiotic relationship: carbon-nitrogen exchange .

18. Mineral soils The concentration of dissociated water in freshly-distilled water is 10 -7 M. This is used to describe acidity-alkalinity, originally called the pouvoir Hydrogéne, which we know now as pH. ACIDEZ DEL SUELO determinará CÓMO estarán disponibles Nutrientes disponibles a través del AGUA DEL SUELO Small quantities of water molecules dissociate : pH = - log [H + ] = - log [10 -7 M] = 7 for fresh distilled water Small values for acid , e.g., the water in Sphagnum bogs can be ~3 Large values for alkaline , e.g., soils on limestone ~8 Suelos Minerales H 2 O OH - + H +

19. How clay particles provide nutrients The root hair cells of plant roots secrete H + into the water around nearby clay particles. These smaller H cations replace the larger macro- and micro-nutrient cations: The released cations are now available for uptake into roots. A clay particle (much enlarged here) is covered with negative charges, anions: Opposites attract, so metal ions with positive charge(s), cations, stick all over the surface of the clay particle: 2H + Ca 2+

20. Summary of soil water chemistry In this summary occurrence of H+ in soil water is shown as the result of respiration of CO 2 and disassociation of carbonic acid H 2 CO 3 that forms Water flow

21. Apoplastic and Symplastic Transport Water and cations can be taken up by roots: apoplastically , i.e. through the cell walls and intercellular spaces, symplastically , i.e. from protoplast to protoplast via plasmodesmata However, at the endodermis the apoplastic pathway is blocked by a waxy deposit of the wall called the Casparian strip . In some plants is the Casparian strip located in the exodermis so that the apoplastic barrier works sooner. Recall transport of sucrose from photosynthesizing cells to phloem

22. Uptake of water and nutrients by roots See Equivalent Fig. 32.2B

23. Film clip

24. 4.Problems in plant nutrition Plant Nutrient Type Visual symptoms Nitrogen Deficiency Light green to yellow appearance of leaves, especially older leaves; stunted growth; poor fruit development. Excess Dark green foliage which may be susceptible to lodging, drought, disease and insect invasion. Fruit and seed crops may fail to yield . Phosphorus Deficiency Leaves may develop purple coloration; stunted plant growth and delay in plant development. Excess Excess phosphorus may cause micronutrient deficiencies, especially iron or zinc. Potassium Deficiency Older leaves turn yellow initially around margins and die; irregular fruit development. Excess Excess potassium may cause deficiencies in magnesium and possibly calcium. W.F. Bennett (editor), 1993. Nutrient Deficiencies & Toxicities in Crop Plants, APS Press, St. Paul, Minnesota. Excess frequently operates through imbalance

25. 5. Nitrogen and the effects of soil organic matter on plant nutrition Nitrogen is the element most required by plants, in terms of weight. It is not a product of weathering of soil particles. There are two sources: fixation of atmospheric nitrogen by bacteria decomposition of organic matter, usually decaying plant material.

26. N-fixing bacteria Fig. 32.13 Most uptake from the soil is in the form of nitrate

27. Spodic soil Organic material is important in agricultural soils both as a source of nitrogen and because it can increase water holding capacity, e.g. biosolids application effects A characteristic of non-agricultural soils is accumulation of organic material and acidification of the soil. Such soils typically develop a very distinct stratification, with organic mater at the top. The organic layers in such soils can have a considerable total quantity of nitrogen but little may be available due to the high acidity, and sometimes lack of oxygen, in the organic layer.

28. Basic Soil-Plant Relationships Organic Matter & Biota Exchangeable ions Surface adsorption Solid phases & Minerals Nutrient Uptake by Plants Soil Solution Soil Air Rainfall, Evaporation, Drainage, Addition of Fertilizer

29. CANTIDAD e INTENSIDAD CANTIDAD (Q) – la cantidad de nutriente en rápido equilibrio con la solución del suelo Intensidad (I) – dada por la actividad o concentración de los iones en solución

30. CANTIDAD Primary Minerals SiO 2 Fe 2 O 3 Al(OH) 3 CaCO 3 MgCO 3 Mica (K) Feldspar (K) Apatite (P) Secondary Clay Minerals and adsorbed ions Kaolinite Montmorillonite Vermiculite Illite Organic Matter

31. Cantidad Total – todo lo que hay en el suelo (de ese elemento) Labil – fracción "relativamente" reactiva Soluble – disuelto en la solución del suelo (= Intensidad) Total Labile/ Available Unavailable Available Soluble

32. Intensidad – Actividad (sn) Dissolved in the soil solution Activity (a) = effective concentration (C) a = γ C γ = activity coefficient (0 - 1) A B B B A A Dilute solution a ≈ C A + B AB A B B B A A Concentrated solution a < C A + B AB X X X X X X X X X X Greater the Ionic Strength of the solution the lower the activity coefficient

33. Activity vs Concentration in Soil Solution 0.0085 0.0255 Al 3+ 0.42 0.75 SO 4 2- 4.26 4.98 NH 4 + 2.23 2.60 K + 0.43 0.71 Mg 2+ 0.98 1.68 Ca 2+ mM mM Activity Concentration Ion

34. Intensity – Solution Activity Activity (a) is related to energy (F) F = RT ln a (R = constant, T = temperature) Everything occurs because of energy differences Water flows down hill Chemical reactions occur if the energy of the products is lower than the energy of the reactants Plants take up nutrients because of energy differences Plant uptake is related to activities not concentrations

35. Quantity and Intensity Quantity Intensity Crop Uptake Fertilizer

36. Buffer Capacity: Chemical reactions occur based on Intensity Plant uptake occurs based on Intensity BUT In a real soil, Buffer Capacity determines Intensity because we are not at equilibrium Plants keep removing nutrients and upsetting the equilibrium We keep adding fertilizer and upsetting the equilibrium

37. Quantity and Intensity >>> Buffer Capacity <<< Quantity Intensity Crop Uptake Fertilizer

38. Quantity and Intensity >>> Buffer Capacity <<< Buffer Capacity - Relationship between the quantity and the intensity Buffer capacity = ∆ Q / ∆ I BC ~ 1 little buffering BC >> 1 well buffered

39. Buffer Capacity Quantity/Intensity Graph (Q/I) Intensity Quantity Soil A Soil B

40. Buffer Capacity Lower Coarse Texture (Sand) Low CEC Low OM Higher Fine Texture (Clay) High CEC High OM Extreme - Fixation P reaction with Fe, Al, Ca K trapped in mica type clays Micronutrient precipitation in high pH soils

41. Basic Soil-Plant Relationships Organic Matter & Biota Exchangeable ions Surface adsorption Solid phases & Minerals Nutrient Uptake by Plants Soil Solution Soil Air Rainfall, Evaporation, Drainage, Addition of Fertilizer

42. The indissoluble link between man and soil is manifest in the very name Adam, derived from Adamiss – a Hebrew noun of feminine gender meaning earth or soil. Adamiss’ name encapsulated ‘maniss,’ meaning origin and destiny: his existence and livelihood derive from the soil to which he is tethered throughout his life and to which he is fated to return at the end of his days. Likewise, the name of Adam’s mate, Hava (rendered ‘Eve’ in translation) literally means ‘living’. Together, therefore, Adam and Eve signify 'Soil and Life.” from “Out of the Earth: Civilization and the Life of the Soil&quot; by Dr. Daniel Hillel , professor emeritus of plant, soil, and environmental sciences at the University of Massachusetts, Amherst. existe un vínculo indisoluble y estrecho entre el hombre y el suelo, que se manifiesta en el nombre ADAN, derivado del hebreo ADAMISS(= sustantivo femenino = tierra o suelo);maniss&quot;contenido en Adamiss, significa origen y destino: por lo tanto la vida y existencia del hombre en gral.derivarían del suelo al cual está ligado a traves de su vida y al que está destinado a regresar al final de sus días. De la misma forma, su compañera, HAVA (EVE) literalmente significa vida. De esta forma, ADAN y EVA,---------> SUELO y VIDA SON