Lurzoruaren

Chromic Luvisols: 100%
Teknikekin

Aukera	Sakonera	Drainatze	Testura Erreakzio - pH-dun	Organikoa Carbon Eroankortasuna - Elektriko	Zorupearen katioia truke	Buztina katioia truke	Kaltzio karbonatoa - Karea	Gypsum Sodium - Trukatu
	Topsoil	3	6.4	0.86	12	38	0	0
	Zorupearen	3	6.4	0.38	15	40	0	0

Lurzoruaren Triangle - Chromic Luvisols

Irudiak - Chromic Luvisols

Definizioa - Chromic Luvisols

Luvisols güclü kahverengi və ya qırmızı argic yeraltı üfüqdə bir (boztəhər) qəhvəyi üzərində qəhvəyi səthi üfüqdə tipik olaraq bir qəhvəyi var. Kromik 150 bir yeraltı lay torpaq səthinin sm, 30 sm və ya daha qalın bir Munsell hue redder daha 7,5 il və ya, həm də ki, 7.5 il bir renk və daha çox, nəm, Parlaq 4 daxilində olan göstərir. Xüsusilə subtropik Luvisols, bir kireçli üfüqdə bilər və ya yumşaq toz əhəng mobil və qırmızımtıl qəhvəyi argic üfüqdə aşağıda baş verir. Torpaq rənglər isti iqlim nisbətən sərin bölgələrdə Luvisols az qırmızı olur. Nəm mühitdə, səthinin torpaq dərəcədə gil və pulsuz dəmir oksidləri tükənəcək ola bilər ki, bir qaranlıq lakin nazik A-üfüqdə bir boztəhər eluviation üfüqdə formaları. Luvisols Aralıq dənizi və Cənubi Avstraliya da əsasən belə Rusiya Federasiyası, Amerika Birləşmiş Ştatları və Mərkəzi Avropanın qərb və mərkəz kimi mülayim rayonlarda, 500-600 milyon ha dünyada artıq uzatmaq, lakin. Subtropik və tropik regionlarda Luvisols əsasən gənc torpaq səthlərə baş verir. Ən Luvisols münbit torpaqları və kənd təsərrüfatı istifadəsi geniş uygundur. Bu mülayim zonasında Luvisols geniş kiçik taxıl, şəkər çuğunduru və yem üçün əkilir; maili ərazilərdə onlar meyvə bağları, meşələr və / və ya otlaq üçün istifadə olunur. Bu tez-tez eroziyaya yuxarı yamacında geniş istifadə olunur isə Luvisols (bu xromlu, kireçli və ya Vertic Qualifier çox) aşınma daşı, əhəng daşı colluvial yataqlarının ümumi olduğu Aralıq dənizi olaraq, aşağı yamacları geniş buğda və / və ya şəkər çuğunduru üçün əkin olunur otlaq və ya ağac bitkiləri üçün əkilmişdir

[1]

Deskribapena - Limosos

Loams ən faydalı "bütün ətrafında" torpaqların və onlar bu gillər gücü və retentiveness ilə, qum və yüngüllük və earliness birləşdirir. Loams qum, 40 faiz 60-ehtiva və gil faizi 15-25. Onlar asan, qabığı və ya crack deyil, həm də əsasən vacibdir ki, bitki qida ilə təchiz, və yoxdur "qədər iş", onların vasitəsilə su hərəkət sərbəst və hələ onlar leachy deyil. Praktiki olaraq bütün təsərrüfat bitkiləri bir loam haqqında qənaətbəxş bitir. Bu, kartof, qarğıdalı, bazar bağçılıq bitkilər və kiçik meyvə, xüsusilə də uyğun deyil, lakin otlar, taxıl, yonca, yonca və pambıq, bu, uyğun tapa bilərsiniz. Yaxşı əkinçilik, drenaj və hər yerdə ən yaxşı təsərrüfatı təcrübə zəruri hissəsi kimi humus əlavə bu cür diqqət başqa heç bir xüsusi müalicə tələb edir. Onlar nisbətən quru mövsüm kimi biber halda, mülayim tropik və subtropik iqlim əkilir əgər etməz, yaxşı drains yaxşı loam bir wetter iqlim ofset kömək elə. Ən çox meyvə ağacları daha uzun yaşayır və onlar balanslaşdırılmış loam inkişaf zaman daha yaxşı verir. Sitrus ağacları yaxşı drenaj istəyirəm, lakin onlar nəmli saxlanılır lazımdır. Loam sitrus üçün yaxşı seçimdir

[2]

Laborantzen - Chromic Luvisols

ale txikiak, azukre-erremolatxa, bazka (zona epela)
baratzak (malda eremuetan)
garia, erremolatxa (hegaletan txikiagoa, Mediterraneoko eskualde), zuhaitz laboreak (goiko maldak, Mediterraneoko eskualdean)

[3] [4]

Metrikak/Eztabaida

Gaia	Balioa	Xehetasunak
Drainatze	3	Atzealdea Bakarra laranja mottles ohikoa den gutxirekin Lurzoruaren esan nahi du lurra neurrizko ondo xukatu Ura lurrean zehar mugitzen, poliki-poliki, urteko aldi batzuetan zehar Ura doan Barne neurrizko sakona da eta iragankorrak edo iraunkorra izan daiteke The soil is wet for only a short time within the rooting depth during the growing season The soil often has a moderately low or lower saturated hydraulic conductivity class within 1 meter of the surface, or the soil experiences periods of high rainfall, or both Definizioa Drainage Class soils refers to the frequency and duration of periods when the soil is saturated with water. Alterations of the water regime by human activities, either through drainage or irrigation, are not a consideration unless they have significantly changed the morphology of the soil. Seven classes of natural soil drainage are recognized 1. very poorly drained 2. poorly drained 3. somewhat poorly drained 4. moderately well drained 5. well drained 6. somewhat excessively drained 7. excessively drained [5] [6]
Lurzoruaren erreferentzia sakonera	100 mm	Erronka Lurzoruaren sakonera mugak root sartze eragina izan dezaketen eta etekin sustraiak eta tuberkuluak eraketa mugak daitezke [7] [8] Definizioa An approximation of actual soil depth can be derived through accounting for relevant depth limiting soil phases, obstacles to roots and occurrence of impermeable layers. Soil depth limitations which affect root penetration and may constrain yield formation (roots and tubers). This is a measurement in cm of reference soil depth. Reference soil depth of all soil units are set at 100 cm, except for Rendzinas and Rankers of FAO-74 and Leptosols of FAO-90, where the reference soil depth is set at 30 cm, and for Lithosols of FAO-74 and Lithic Leptosols of FAO-90, where it is set at 10 cm [7] [9]
Base saturation	89%	Erronka infiltrazio gaitasun txikia ureztatze ez da posible nekazaritza da laboreak toleranteak waterlogging azaleratu mugatuta (adibidez, arroza, belarrak) produktibitate txikia da Strongly alkaline soils are often highly sodic (Na reaching toxic levels), badly structured (columnar structure) and easily dispersed surface clays 7.5 (Oso alkalinoak) pH gainetik, hala nola, burdina, manganesoa, eta fosforo gisa nutrienteak batzuk eskuragarri daude gutxiago Aholkuak Lurzoruaren pH jaistea, gehitu azido, iturri bat, hala nola birrindu hostoak, sufre, sawdust edo zohikatza goroldioa bezala Atzealdea Base Saturazioaren balioak askotan korrelazioa gertu a pH lineala erakusten ditu Base saturazioa>% 80 saturatuak lurzoruaren baldintza askotan kare, batzuetan sodic edo gatz adierazten du [7] Definizioa The base saturation of the topsoil measures the sum of exchangeable cations (nutrients) Na, Ca, Mg and K as a percentage of the overall exchange capacity of the soil (including the same cations plus H and Al). The value often shows a near linear correlation with pH. Critical values as follows Base Saturation < 20 % = desaturated soils, similar interpretation as extremely acid pH Base Saturation of 20 – 50 % = acid conditions Base Saturation of 50 – 80 % = Soil conditions of neutral to slightly alkaline which are ideal conditions for most crops Base Saturation > 80% indicates saturated conditions often calcareous, sometimes sodic or saline [7] [8]
Kaltzio karbonatoa CaCO3 - Karea	0% Pisua	Atzealdea Kaltzio karbonato maila baxua hobetzeko lurzoruaren egitura eta, oro har, laborantza ekoizpen onuragarriak dira [7] [10] Definizioa This gives the calcium carbonate (lime) content in the topsoil. Calcium carbonate is a chemical compound (a salt), with the chemical formula CaCO3. It is a common substance found as rock in all parts of the world, and is the main component of shells of marine organisms, snails, and eggshells. Calcium carbonate is the active ingredient in agricultural lime, and is usually the principal cause of hard water. It is quite common in soils particularly in drier areas and it may occur in different forms as mycelium-like threads, as soft powdery lime, as harder concretions or cemented in petrocalcic horizons. Low levels of calcium carbonate enhance soil structure and are generally beneficial for crop production but at higher concentrations they may induce iron deficiency and when cemented limit the water storage capacity of soils. In agronomic sense relevant limits are None to very low < 2 Low = 2 – 5 Moderate = 5 – 15 High = 15 – 40 Very High > 40 [7]
Karbono organikoaren	0.86% Pisua	Erronka Lurzoru mineral karbono Guztira organikoak (puntu): 1 eta 5 = maila egokia, <1 = posible C organikoaren galera higadura edo beste prozesu batetik adieraz dezake, batez epel edo hotzago eremuetan [11] [12] [7] [13] [14] [15] Aholkuak Gai organiko handitzea material organikoa itzuli lurzoru eta goi-hondakina laboreak eta sakona edo trinko-rooting-laborantza errotazioak gehituz Ways to increase organic matter contents of soils: compost, cover crops/green manure crops, crop rotation, perennial forage crops, zero or reduced tillage, agroforestry [11] [12] [7] [13] [14] [15] Atzealdea Carbon Organikoa da, elkarrekin pH batera, osasuna lurzoruaren egoerari buruzko adierazle sinple onena Lurzoruaren handiko karbono organikoa (SOC) lurzoruan Ertaina laborantza handiko errendimendu adierazle bat da Moderate to high amounts of organic carbon are associated with fertile soils with a good structure [11] [12] [7] [13] [14] [15] Definizioa This gives the percentage of organic carbon in the topsoil. Organic Carbon is, together with pH, the best simple indicator of the health status of the soil. Moderate to high amounts of organic carbon are associated with fertile soils with a good structure. Soils that are very poor in organic carbon (<0.2%), invariable need organic or inorganic fertilizer application to be productive. Soils with an organic matter content of less than 0.6% are considered poor in organic matter. The following classes are suggested to prepare maps of organic carbon status for mineral soils Code 1 < 0.2% organic carbon Code 2 = 0.2 – 0.6% organic carbon Code 3 = 0.6 – 1.2% organic carbon Code 4 = 1.2 – 2.0% organic carbon Code 5 > 2.0% organic carbon [7] [9]
Katioia underpressure - Buztina	38 cmol/kg	Erronka Lurzoru CEC Behe gehiago egongo dira, potasio eta magnesioa (eta beste katioi) gabeziak garatzea, lurzoru CEC altua dira gutxiago Katioi horien galerak lixibiatzearekin jasan bitartean.. For sandy soils, the addition of a large amount of potassium at one time can lead to high losses due to leaching. This is because the potassium adds a large amount of cations at one time and soil cannot hold on to the excess potassium. Therefore, frequent additions of smaller amounts of potassium can work better to add potassium to the soil than one large amount Aholkuak Txikiagoa CEC, azkarrago lurzoruaren pH izango da denbora hori murriztu Sandy lurzoru buztin lurzoru baino liming maizago eskatzen The CEC handiagoa, orduan eta handiagoa izango kare kopuru hori gehitu behar lurzoruaren pH handitzeko sandy soils need less lime than clay soils to increase soil pH The CEC handiagoa, orduan eta handiagoa izango lurzoru kopuru additivated lurzoruaren lurzoruaren pH aldatu beharko da, bai, karea edo bikarbonato handiko ureztatzeko ura, edo noiz batera pH handituz nitrogeno ongarri edo elemental sufre pH jaitsiz Atzealdea CEC 20 cmol 50era sorta / kg buztin kaolinite gaur buztin mistoak dituen lurzoru CEC moderatua dela adierazten du Kaolinite batzuen presentzia esan nahi du lurra zertxobait tropikalak, lixibiatzearekin klima batean existitzen CEC oso lurzoruaren ehundura eta materia organikoaren edukia menpe Oro har, goi mailako buztina eta materia organikoaren edukia lurzoruan, handiagoa CEC Lurzoru gehienak CEC lurzoruaren pH gehikuntza handitzen Lurzoru Oso azido H + eta Al3 + kontzentrazio altua izango dute Lurzoru neurrizko alkalinoak neutral asmoz, Ca2 + eta MG2 + menderatzeko Lurzoru lehorretan Gaizki xukatu Na adsorb daiteke oso kopuru handiko Ezinbestekoa landare nutriente katioiak (K +, Ca 2+, Mg 2+, eta NH4 +) ehuneko txiki bat bakarrik 'solteak' lurzoru uretan eta, beraz, landare geureganatze egongo dira, beraz CEC garrantzitsua da ematen duelako mantenugaien urtegia Lurzoruaren uretan Katioiak duten rootzone azpian garbitu egiten dira urak ordez katioiak antzina CEC doazen arabera 'Buffer ahalmena' kazioa nutrienteak existitzen baita lurzoruaren pH gisa Kontzentrazio arinagoa amore zuria, horia edo argi laranja kolore Kaolinite bat txikitzeko-olatuak baxua gaitasuna eta bat katioien trukerako baxua ahalmena dauka Definizioa This gives the cation exchange capacity of the clay fraction in topsoil. The type of clay mineral dominantly present in the soil is often characterizes a specific set of pedogenetic factors in which the soil has developed. Tropical, leaching climates produce the clay mineral kaolinite, while confined conditions rich in Ca and Mg in climates with a pronounced dry season encourage the formation of the clay mineral smectite (montmorillonite). Nutrient retention capacity is of particular importance for the effectiveness of fertilizer applications and is therefore of special relevance for intermediate and high input level cropping conditions. Nutrient retention capacity refers to the capacity of the soil to retain added nutrients against losses caused by leaching. Plant nutrients are held in the soil on the exchange sites provided by the clay fraction, organic matter and the clay-humus complex. Losses vary with the intensity of leaching which is determined by the rate of drainage of soil moisture through the soil profile. Clay minerals have typical exchange capacities, with kaolinites generally having the lowest at less than 16 cmol/kg, while smectites have one of the highest with a CEC per 100g clay being 80 cmol/kg, or more. The classes generally used in the Harmonized World Soil Database are Class 1 = < 20 cmol/kg clay (kaolinite dominant) Class 2 = 20-50 cmol/kg clay (mixed with kaolinite present) Class 3 = >50-100 cmol/kg clay (mixed, illite) Class 4 = >100 cmol/kg clay (montmorillonite) NOTE: Soils developed on volcanic materials rich in amorphous sesquioxides may have very higher values (over 150 cmol/kg) [7]
Katioia underpressure - Lurzoruaren	12 cmol/kg	Erronka A CEC balioak handiagoak izateak adierazle bat dela lurzoruaren katioiak eduki gaitasun handiagoa du da Lurzoruaren CEC altuak katioiak eduki, beraz, ongarri edo kare-tasa handiagoa, askotan lurzorua CEC altua aldatu behar ahalmen handiagoa du high CEC is an indicator that there is a high reserve of nutrients in the soil Soils with low CEC can take a large amount of fertilizer or lime to correct A high CEC soil requires a higher soil cation level, or soil test, to provide adequate crop nutrition Aholkuak The CEC handiagoa, orduan eta handiagoa izango kare kopuru hori gehitu behar lurzoruaren pH handitzeko Sandy lurzoru buztin lurzoru baino karea gutxiago behar nahi duzun mailetara pH handitzeko The CEC handiagoa, orduan eta handiagoa izango lurzoru kopuru additivated lurzoruaren lurzoruaren pH aldatu beharko da, bai, karea edo bikarbonato handiko ureztatzeko ura, edo noiz batera pH handituz nitrogeno ongarri edo elemental sufre pH jaitsiz.. Acceptable saturation ranges for Soil CEC = 6-10: 3-5% K, 50-70% Ca, 8-20% Mg Definizioa This gives the cation exchange capacity in the topsoil. The total nutrient fixing capacity of a soil is well expressed by its Cation Exchange Capacity. Soils with low CEC have little resilience and can not build up stores of nutrients. Many sandy soils have CEC less than 4 cmol/kg. The clay content, the clay type and the organic matter content all determine the total nutrient storage capacity. Nutrient retention capacity is of particular importance for the effectiveness of fertilizer applications and is therefore of special relevance for intermediate and high input level cropping conditions. Nutrient retention capacity refers to the capacity of the soil to retain added nutrients against losses caused by leaching. Plant nutrients are held in the soil on the exchange sites provided by the clay fraction, organic matter and the clay-humus complex. Losses vary with the intensity of leaching which is determined by the rate of drainage of soil moisture through the soil profile. Values in excess of 10 cmol/kg are considered satisfactory for most crops. This is reflected by the following code system used in the Harmonized World Soil Database Code 1 = Cation Exchange Capacity < 4 cmol/kg Code 2 = Cation Exchange Capacity of 4-10 cmol/kg Code 3 = Cation Exchange Capacity > 10 -- 20 cmol/kg Code 4 = Cation Exchange Capacity > 20 -- 40 cmol/kg Code 5 = Cation Exchange Capacity > 40 cmol/kg [7] [9]
Buztina - Ehuneko - Pisua	24% Pisua	Erronka Hustubideak gaizki, aire espazio batzuk ditu, iristen denean poliki udaberrian, heavy lantzen Propietate fisiko kaltegarriak Pobre lan erraztasuna Behe-teknologia gizarteetan arrakastaren kudeaketa gehiegi eskatu zuhaitz laboreak ezin zorupean erro Tree roots are damaged as the soil shrinks and swells Low structural stability Very susceptible to water erosion Aholkuak Ez magaletan 5 ehuneko arable mozketan batez erabili Gutxiago erabili groundcover laboreak aldapetan 5 ehuneko baino Terracing denean, erabilera Azalera drainatze slumping saihesteko Gehitu materia organikoa Tilth, lan erraztasuna, eta barne-drainatze hobetzeko Drainatze hobetu bada, landareak ondo hazten lurzoru buztin buztin beste lurzoru askotan baino nutriente gehiago dauka geroztik Use caution when plowing and tilling Do not plow excessively wet clays, or they will become cloddy Till clay soils only when they are dry and crumble readily In temperate climates, Plow clay soils in the fall, then leave them rough and exposed to the mellowing action of freezing and thawing Frequent, shallow tillage can help to prevent crusting of the topsoil Maize crops require deep cultivation and ridges in the soil to improve drainage (maize cannot tolerate waterlogging and can die if it stands in water for as long as 2 days) Adding lime to clay soils can improve the soil's texture to result in looser and more porous soil Urte azpiko drainatze Erabili lurraren pisua na murrizteko aldi lehorretan gehigarria kenduz Under-drainage promotes aeration and warmth in clay soils Loosen clay soils by mixing them with humus or sand Barnyard manure or a green manure crop will lighten heavy clay soil To lighten clay soil, spread sand on top of the clay soil and plow it under [16] [17] [18] [19] Atzealdea Buztina lurzoru sentitzen beltza edo lumpy eta zurrunak oso bustia, eta gogorra eta leuna lehorra da [20] [21] Definizioa This measure the percentage of clay in the topsoil. Clay is naturally occurring firm earthy material, composed primarily of fine-grained (diameter less than 0.002mm) that is plastic when wet and hardens when heated and that consists primarily of hydrated silicates or aluminum. Clay is mostly composed of clay minerals which are phyllo-silicate minerals and minerals which impart plasticity and harden when fired or dried. The definition of "fine grained" used above is particles smaller than 2 µm, colloid chemists (and Eastern European soil scientists) may use 1 µm. The clay content of the soil is listed as a percentage (0 to 100) of the total weight of the soil. Soils is with a high percentage of clay, such as Vertisols, are used for very extensive (grazing, collection of fuelwood, and charcoal burning) through smallholder post-rainy season crop production (millet, sorghum, cotton and chickpeas) to small-scale (rice) and large-scale irrigated agriculture (cotton, wheat, barley, sorghum, chickpeas, flax, noug [Guzotia abessynica] and sugar cane). Cotton is known to perform well on Vertisols, allegedly because cotton has a vertical root system that is not damaged severely by cracking of the soil. Tree crops are generally less successful because tree roots find it difficult to establish themselves in the subsoil and are damaged as the soil shrinks and swells. Management practices for crop production should be directed primarily at water control in combination with conservation or improvement of soil fertility [7]
Hartxintxar - Ehuneko - Bolumena	9% Pisua	Erronka Gravel rooting baldintzak eta lurzoruen workability eragina izan dezake Materia organiko altua izan daiteke [7] [22] [23] [24] Aholkuak Materia organikoa gehitu ernaltzeko aldian-aldian Erabili ilar legar mulch gisa belarrak eta beste lehorte-tolerantea landareen sustraiak babestu Ilarra legar bero islatzen eta drainatze ona ematen du [7] [22] [23] [24] Definizioa Hau bolumenaren legar ehunekoa landare lur neurtzen. Gravel materialen ehunekoa lurzoru hori 2 mm baino handiagoko Hemen nabarmentzen. Gravel can affect the rooting conditions and workability of soils. The percentage of gravel in the soil is listed on a scale of 0 to 100 percent volume [18] [25]
Harea - Ehuneko - Pisua	47% Pisua	Erronka Sand lehortu azkar eta elikagai falta daiteke mantenugaiak euri edo ureztatze lurzoruaren bidez erraz garbitu baitaitezke materia organikoaren edukia eta jatorrizko emankortasuna gutxikoak hezetasuna eta elikagaiak mantentzeko gaitasuna gutxikoak low in cation exchange and buffer capacities rapidly permeable (i.e., rapid movement of water and air) In the perhumid tropics, sandy soils are chemically exhausted and highly sensitive to erosion Aholkuak Erabili maiz ureztatzeko, drainatze artifiziala, eta ongarri egokia (aplikazio bakoitzeko nutriente kantitate maizago baina txikiagoa) Guztira laborantza per ongarri kantitate nahiko handia izaten dira Manage erosion and chemical exhaustion in perhumid tropical soils Add organic matter to improve texture, increase water-holding capacity, and improve fertility [26] [19] [20] [27] [28] [29] Atzealdea Sand free-behera hustutzen, gritty sentitzen du, iristen denean, azkar, eta erraza da lantzen Feel gritty, ez zurrunak da [20] Definizioa Sand comprises particles, or granules, ranging in diameter from 0.0625 mm (or 1/16 mm) to 2 millimeters. An individual particle in this range size is termed a sand grain. Sand feels gritty when rubbed between the fingers (silt, by comparison, feels like flour). This measures the percentage (0 to 100) by weight of sand in the topsoil. Sand is commonly divided into five sub-categories based on size very fine sand (1/16 - 1/8 mm diameter) fine sand (1/8 mm - 1/4 mm) medium sand (1/4 mm - 1/2 mm) coarse sand (1/2 mm - 1 mm) and very coarse sand (1 mm - 2 mm) [7] [9]
Silt - Ehuneko - Pisua	29% Pisua	Erronka higadura [30] Aholkuak Laborantza eta higaduraren kontrola esaterako terracing, sestra plowing, mulching eta estaldura begetalak erabiltzea neurri trinkotzea eta egitura hondatzea larriak lurzorua kontserbatzeko lagundu Fertilizers and/or lime are preconditions for continuous cultivation [31] [32] [30] Atzealdea Lurzoru silty egitura ahul bat (desegin dute erraz) lan erraza Lohi sentsazioa leuna eta xaboi da Feel leuna edo irinez bezalakoa da thumb eta hatz artean ezabatzen denean zinta bat ahula (2,5 cm baino gutxiago luzea) egiten [31] Definizioa Silt is produced by the mechanical weathering of rock, as opposed to the chemical weathering that results in clays. This mechanical weathering can be due to grinding by glaciers, eolian abrasion (sandblasting by the wind) as well as water erosion of rocks on the beds of rivers and streams. Silt is sometimes known as 'rock flour' or 'stone dust', especially when produced by glacial action. Mineralogically, silt is composed mainly of quartz and feldspar. This measures the percentage (0 to 100) by weight of silt in the topsoil. Soils with a lot of silt make excellent farm land, but erode easily. Erosion removes topsoil, reduces levels of soil organic matter, and contributes to the breakdown of soil structure. This creates a less favorable environment for plant growth. Soil erosion can be avoided by: maintaining a protective cover on the soil, creating a barrier to the erosive agent, modifying the landscape to control runoff amounts and rates. Specific practices to avoid water erosion: growing forage crops in rotation or as permanent cover; growing winter cover crops; interseeding; protecting the surface with crop residue; shortening the length and steepness of slopes; increasing water infiltration rates; improving aggregate stability. Specific practices to avoid wind erosion: maintaining a cover of plants or residue, planting shelterbelts, stripcropping, increase surface roughness, cultivating on the contour, maintaining soil aggregates at a size less likely to be carried by wind [7]
Eroankortasun elektrikoa	0.1 dS/m	Erronka inhibituta ur geureganatze ureztatzeko eta waterlogging gehiegizko lurzoruaren gazitasun eragin dezake [9] [33] Aholkuak Kontrol lurzoruaren gazitasun ureztatzeko uraren% 10-20 ahalbidetuko lurzoruaren Leach, eta orduan izango xukatu eta alta eman [9] [33] Atzealdea ECE, edo eroankortasun elektrikoa, lurzoruaren gazitasun-maila neurri bat da [7] Definizioa This gives the electrical conductivity of the topsoil. Coastal and desert soils in particular can be enriched with water-soluble salts or salts more soluble than gypsum. The salt content of a soil can be roughly estimated from the Electrical Conductivity of the soil (EC, expressed in dS/m) measured in a saturated soil paste or a more diluted suspension of soil in water. Accumulation of salts may cause salinity. Excess of free salts referred to as soil salinity is measured as Electric Conductivity (EC in dS/m) or as saturation of the exchange complex with sodium ions. Salinity affects crops through inhibiting the uptake of water. Moderate salinity affects growth and reduces yields; high salinity levels may kill the crop. Crops vary considerably in their resistance and response to salt in soils. Some crops will suffer at values as little as 2 dS/m (spinach) others can stand up to 16 dS/m (date palm). Agronomic relevant limits are Very low ECe < 2 dS/m Low ECe = 2 – 4 dS/m Moderate ECe = 4 – 8 dS/m High ECe = 8 – 16 dS/m Very High ECe > 16 dS/m Some plants are more tolerant to a high salt concentration than others. Highly tolerant plants include date palm, barley, sugarbeet, cotton, asparagus, spinach [7] [9]
Igeltsua edukia CaSO4	0% Bolumena	Aholkuak Ur kultura erabiliz SO4 nahasketa kontzentrazioa handitzeko (K2SO4 + MgSO4) NO3, K, Mg eta sufre asimilatzea handitzen baina Ca eta P asimilatzea gutxitzen Erabili lurzoruaren terracing higadura saihesteko Use supplementary irrigation to increase productivity where water resources are available Harrow the land after harvesting and before the rainy season to improve the infiltration of water and conserve soil moisture Increase organic matter by replacing fallow by small-grain leguminous crops in the wheat-fallow rotations Add manure Use subsoiling to break the cemented gypsic subsoil to improve root penetration and reduces susceptibility to drought, especially in the case of fruit and forest trees Do not mix the topsoil and subsoil Apply nitrogen and phosphorus to cereals N is generally applied where rainfall exceeds 260 mm annually Phosphorus fertilizers increase the yield of cereals, especially under low rainfall For irrigated gypsiferous soils: The use of (NH4)2CO3 solution was found to cause the optimum elimination of gypsum in gypsiferous soils with both low and high levels of gypsum; In general, there is need for ample nitrogen fertilizers for crops grown on gypsiferous soils, especially under irrigated agriculture. There are no significant differences between the requirements of crops for nitrogen on gypsiferous and non-gypsiferous soils; Molybdenum applications might benefit many plants, especially legumes [34] [7] Atzealdea Gehienez 2 puntu lurzoruan igeltsua landare hazkundea bultzatzen duela Nekazaritza laboreak gehienak ez duten lurzoruetan hazten igeltsua edukia oso txikia da Definizioa Calcium sulphate (gypsum) content in topsoil. Gypsum is a chemical compound (a salt) which occurs occasionally in soils particularly in the driest areas of the globe where it can occur in a flower-like form typically opaque with embedded sand grains called desert rose. In soils it may occur in fibers, crystals or soft. Research indicates that up to 2 percent gypsum in the soil favours plant growth, between 2 and 25 percent has little or no adverse effect if in powdery form, but more than 25 percent can cause substantial reduction in yields. It is suggested that reductions are due in part to imbalanced ion ratios, particularly K:Ca and Mg:Ca. Gypsum strongly limits available soil moisture. Tolerance of crops to gypsum varies widely (FAO, 1990; Sys, 1993). Relevant limits are considered the following None to very low CaSO4 < 2% Low CaSO4 = 2 – 5% Moderate CaSO4 = 5 – 25% High CaSO4 = 25 – 40% Very High CaSO4 > 40%
Soil reaction - pH-dun	6.4 -log H+	Erronka 3,0ko pH Peat goroldioa lurzorua gehigarri gisa gomendatzen dezake, baina zohikatza goroldioa elikagai-pobrea, garestia da, eta baliabide ez-berriztagarritzat da [35] [36] [37] [38] [39] Aholkuak The ideal pH laboreak gehienak barruti 6,5 7,0 da, beraz laboreak batzuk apur pH optimoa hazkunde doitze eska dezake Lurzoruaren pH jaistea, gehitu azido, iturri bat, hala nola birrindu hostoak, sufre, sawdust edo zohikatza goroldioa bezala Gehitu material alkalinoa, hala nola lurzoruaren azidotasuna txikitzeko kareharria bezala Aplikatu 2,3 30 metro karratuko karea kg pH igotzeko puntu bat Applying wood ashes will raise soil pH--Wood ashes contain up to 70 percent calcium carbonate, as well as potassium, phosphorus, and many trace elements. Because it is powdery, wood ash is a fast-acting liming material Limit the application of wood ashes to 1 kg per 30 square meters and only apply it every other year in the same area Breed aluminum-tolerant crops [35] [36] [37] [38] Atzealdea Landare espezie askok lurzoru azido edo alkalinoak egokituta The availability of many plant nutrients (for example, P), non-essential elements (for example, Al, Cd, Pb), and essential trace elements (for example, Mn, Fe, Cu, Zn) is strongly dependent on soil pH (Miller and Gardiner 2001) Generally, metal cations (for example, Mn, Fe, Ni, Cu, Zn, Cd, Pb) become more available as pH decreases, while oxyanions (for example, SO4) become more available at alkaline pH levels Soil pH is strongly dependent on the chemical weathering environment. Soils in hot, humid areas and even mesic, wetter areas tend to be more acidic than those of much drier areas. Vegetation communities in those areas tend to be adapted to the soil conditions in which they developed [7] [40] [41] Definizioa Hau lurzorua zorupean erreakzioa ematen. pH, soil-ura irtenbide bat neurtua, garraztasuna eta alkalinity lurzoruaren neurria da. Bost pH klase nagusien hemen hartzen diren agronomiko partida esanahi bat pH < 4.5 = Extremely acid soils include Acid Sulfate Soils (Mangrove soils, cat clays). Do not drain because by oxidation sulfuric acid will be produced and pH will drop lower still pH 4.5 – 5.5 = Very acid soils suffering often from Al toxicity. Some crops are tolerant for these conditions (Tea, Pineapple) pH 5.5 –7.2 = Acid to neutral soils - these are the best pH conditions for nutrient availability and suitable for most crops pH 7.2 – 8.5 = These pH values are indicative of carbonate rich soils. Depending on the form and concentration of calcium carbonate they may result in well structured soils which may however have depth limitations when the calcium carbonate hardens in an impermeable layer and chemically forms less available carbonates affecting nutrient availability (Phosphorus, Iron) pH > 8.5 = Indicates alkaline soils often highly sodic (Na reaching toxic levels), badly structured (columnar structure) and easily dispersed surface clays [7] [42]
Trukagarriak sodio	1%	Definizioa This gives the exchangeable sodium percentage in the topsoil. The exchangeable sodium percentage has been used to indicate levels of sodium in soils it is calculated as the ratio of Na in the CEC (or sum of cations) ESP= Na*100/CECsoil. Alternatively SAR (Sodium Adsorption Ratio) has been used (SAR= Na/Square root ((Ca+Mg)/2)) to indicate levels of sodium hazards for crops. Excess of free salts referred to as saturation of the exchange complex with sodium ions, which is referred to as sodicity or sodium alkalinity and is measured as Exchangeable Sodium Percentage (ESP). Sodicity causes sodium toxicity and affects soil structure leading to massive or coarse columnar structure with low permeability. Sodic soils have a low infiltration rate, they are poorly aerated and difficult to cultivate. Thus, sodic soils adversely affect the plants' growth. Agronomic relevant limits are Low ESP < 6% Moderate ESP = 6 – 15% High ESP = 15 – 25% Very High ESP > 25% [7] [9]
Erreferentzia ontziratu dentsitatea	1.54 kg/dm3	Aholkuak To reduce high bulk density and compaction, minimize soil disturbance and production activities when soils are wet, use designated field roads or rows for equipment traffic, reduce the number of trips across the area, and maintain or increase soil organic matter Use grazing systems that minimize livestock traffic and loafing, provide protected heavy use areas, and adhere to recommended minimum grazing heights Use conservation crop rotation, cover crop, deep tillage, prescribed grazing residue, and tillage management Avoid plowing, timber harvesting, or compaction of the soil [43] [13] [14] [15] Atzealdea Lurzoruaren dentsitate ontziratu lurzoruaren trinkotzea adieraz dezake, baina ez da askotan lurzorua faktore partikula tamaina banaketa, organikoak lurzoruaren materia edukia, eta lodia pasarte edukiak barne menpeko Bulk dentsitatea harea eta rock edukia handitzen den heinean handitzen Bulk density decreases as the organic matter content increases A mineral soil with “ideal” physical properties has 50 percent solids and 50 percent pore space occupying a given volume of space At optimal water content, half the pore space is filled with water (such a soil will have a bulk density of 1.33 g/cm3) Roots usually grow well in soils with bulk densities of up to 1.4 g/cm3 Root penetration begins to decline significantly at bulk densities above 1.7 g/cm3 Above 1.5 g/cm3, there is an increasing probability of adverse effects from soil compaction or high rock content Coarse fragments—Soils with a coarse fragment content of > 50 percent to have a greater probability of adverse effects from infiltration rates that are too high, water storage capacity that is too low, more difficult root penetration, and greater difficulty in seed germination and seedling growth A high contents of coarse fragments can limit soil productivity [43] [13] [14] [15] Definizioa Reference bulk density is a property of particulate materials. It is the mass of many particles of the material divided by the volume they occupy. The volume includes the space between particles as well as the space inside the pores of individual particles. This is a measurement in kg/dm3 of the topsoil reference bulk density. Bulk density reflects the soil’s ability to function for structural support, water and solute movement, and soil aeration. High bulk density is an indicator of low soil porosity and soil compaction. It may cause restrictions to root growth, and poor movement of air and water through the soil. Compaction can result in shallow plant rooting and poor plant growth, influencing crop yield and reducing vegetative cover available to protect soil from erosion. By reducing water infiltration into the soil, compaction can lead to increased runoff and erosion from sloping land or waterlogged soils in flatter areas. In general, some soil compaction to restrict water movement through the soil profile is beneficial under arid conditions, but under humid conditions compaction decreases yields. On cropland, long-term solutions to bulk density and soil compaction problems revolve around decreasing soil disturbance and increasing soil organic matter. A system that uses cover crops, crop residues, perennial sod, and/or reduced tillage results in increased soil organic matter, less disturbance and reduced bulk density. Additionally, the use of multi-crop systems involving plants with different rooting depths can help break up compacted soil layers [7] [32] [44]
Nitrogeno (N)		Erronka Lurzorua landareak kaltetu dezakete nitrogeno gehiegi Nitrogeno gehitzea erraza da, baina gehiegizko nitrogenoa kendu lurzoruan zailagoa da Lurzoruan nitrogeno gehiegi fruta eta lore landareak gaitasuna murrizten du [45] [13] [14] [46] Aholkuak Organic methods of adding nitrogen to the soil include: adding composted manure to the soil, planting a green manure crop such as borage, planting nitrogen-fixing plants such as peas or beans, and adding coffee grounds to the soil, but be careful when adding coffee grounds as this practice also creates acidity and lowers pH of the soil. Organic methods require more time than inorganic methods, but they can result in a more even distribution of the added nitrogen. Non-organic methods of adding nitrogen to the soil include the use of chemical fertilizers. A high-nitrogen fertilizer will have a high first number in the NPK ratio, for example 10-10-10. Nitrogen-containing chemical fertilizers act quickly to add nitrogen to the soil, but the nitrogen also leaves the soil quickly. If there is too much nitrogen in the soil, plant squash, cabbage, broccoli or maize which will use up large amounts of nitrogen while they grow. Note: while these plants absorb the excess nitrogen in the soil, they may look unhealthy and may produce low yields [45] [13] [14] [46] Atzealdea Nitrogeno Guztira lurzoru mineral (puntu):> 0.5 = Handia - nitrogeno erreserba bikaina 0,1 0,5 = Ertaina - maila egokia <0,1 = Txikia - N. organikoaren galera adieraz dezake Nitrogen is essential for plant growth. Plants will not grow or produce without sufficient nitrogen When legumes and other nitrogen fixing plants and the bacteria called Rhizobium work together to store the nitrogen, they are creating a green warehouse in the soil. While they are growing, they release very little nitrogen into the soil, but when they are done growing and they die, their decomposition release the stored nitrogen and increases the total nitrogen in soil. Their death makes nitrogen for plants available later on. When the plant stores the nitrogen in the roots, it produces a lump on the root called a nitrogen nodule. This is harmless to the plant but very beneficial to the farm [45] [13] [14] [46]
Fosforoa (P)		Erronka Oro har, zaila da landareak, fosforo (P) xurgatzeko beraz, normalean, ez da kezka bat landareak gehiegi P. xurgatzen du: Lurzoru hazi Olsen-ateragarrien P mailak dituzten 10 mg gainetik Landareak / kg normalean ez du gehitu P. erantzuten Do not overuse P: soils with very high levels of extractable P may have a deleterious effect on water quality if such soils are subjected to erosion and the soil particles end up in receiving waters [47] [13] [14] [46] Aholkuak Ustiategiak-organikoak lortzeko, erabili fosfato-duten ongarriak, hala nola, PK gisa P balio handia (erdiko balioa) batera Use bone meal or rock phosphate to correct a phosphorus deficiency Add compost to the soil to help plants take up the phosphorus that is already in the soil [47] [13] [14] [46] Atzealdea Fosforo landare hazkunde eta garapenerako beharrezko elikagai ezinbestekoa da. Landareak bihurtzeko beste nutriente ordenan plantaren hazten laguntzen du Phosphorus is the "P" component of N-P-K fertilizers. The availability of soil P to plants depends on the forms of P in soils and soil pH In acid soils, most plant-available P is associated with Fe and Al oxides and is best extracted with the Bray 1 extractant (0.03 M NH4F + 0.025 M HCl). The Bray 1 extractant is applicable to soils with a pH below 6.8, but not to near-neutral or alkaline soils because the acid in the extract begins to dissolve Ca phosphates. These Ca phosphates usually release only small amounts of P for plant uptake unless they begin to dissolve under more acid conditions. Generally, deficiency symptoms are not exhibited by plants growing in soils with Bray 1 levels above 15 mg/kg (Soil and Plant Analysis Council 1999) In alkaline soils, most soil P is associated with Ca, either sorbed to carbonate minerals or existing as various Ca phosphate minerals, the most common of which is apatite. The Olsen (pH 8.5, 0.5 M NaHCO3) extractant was developed to measure plant-available P in alkaline soils, but it also works in many acid soils. The bicarbonate ions release P sorbed to many mineral surfaces that is plant available without dissolving the otherwise plant-unavailable P in Ca phosphates [47] [13] [14] [46]
Potasio (K)		Aholkuak Potasio ongarri batzuetan potash ongarri deritzo potasio ongarri potasio bakarrik (K) dauka edo goi K balioa du Compost made primarily from food byproducts, especially banana peels, is an excellent source of potassium for the soil when used as a soil additive Use wood ash as a light application to avoid burning plants Greensand can be used as a soil additive to add potassium to the soil Because potassium deficiency in plants is difficult to diagnose visually, test the soil before adding more potassium [48] [13] [14] [46] Atzealdea Landareak guztiekin, potasio landarearen barruan funtzio guztiak laguntzen. Landare bat nahikoa potasio ditu dizunean izango da landarea hobeto orokorra izan Potassium is important to plant growth and development. Potassium helps: plants grow faster, use water better and be more drought resistant, fight off disease, resist pests, grow stronger, and produce more crops K (mg/kg): > 500 = High – excellent reserve 100 to 500 = Moderate – adequate levels for most plants < 100 = Low – possible deficiencies [48] [13] [14] [46]

Zero Tillage

Conservation tillage systems such as zero tillage cause minimum disturbance to the soil after the previous crop has been harvested. In zero tillage, the ideal is to plant direct into the soil, without hoeing or plowing. Tillage is reduced to ripping planting lines or making holes for planting with a hoe. Crop residues are left in the field to reduce soil erosion, conserve moisture, inhibit weed growth, and act as green manure. Zero tillage is not recommended when disease is present. To manage disease, crop residues must be either removed from the field and destroyed or deeply ploughed to reduce sources of disease infection and spread.

Advantages of conservation tillage include less machinery, labour and fuel, as well as reduced soil erosion and compaction. Disadvantages of conservation tillage include lower soil temperatures, slower germination and emergence when direct sowing is used, slower early growth, delayed competition with weeds, higher incidence of root diseases, heavier crop residue, the possibility of more difficult planter operation, weed spectrum changes, and potential increase of soil insect pests or insects that spend part of their life cycle in the soil (e.g. cutworms, thrips, leafmining flies, grubs). Cultivation exposes these pests to desiccation by the sun heat and to predation by natural enemies.

Green Manuring

Green manure legumes create nitrogen in the soil by fixing it from the atmosphere.

Benefits of Green Manure Cover Crops

Easy to grow
Increases soil organic matter
Reduce soil losses from wind and water erosion
If it is a legume, it can fix nitrogen. When the legume is mature, chopped up and added to the soil, it will add nitrogen to the soil which will be used by later crops on the land.
The roots of the green manure crops extract nutrients from deep in the soil.
The deep roots work to break up and aerate the soil
When the green manure is added to the soil, it works to lighten and loosen the soil to aerate and improve drainage, making the soil healthier for later crops. After tilling in a green manure crop, we see the soil level in the farm beds raise several inches. The soil is loose and no longer compacted.
Green manure crops include jack beans, perennial peanut, and Mucuna.
These plants help the main crop by increasing soil fertility by adding nitrogen to the soil by nitrogen fixation.
They add biomass (organic matter) to the soil.
As cover crops, they reduce soil loss.

Planting Green Manure Crops

Green manure crops can be planting using intercropping with the main crop or by using crop rotation in which the green manure crop is planted in-between plantings of the main crop. For intercropping, plant the legume seeds in rows between rows of the main crop. Plow the legumes into the soil at the start of the rainy season.

In crop rotation, plant legumes after the main crop has been harvested. The legumes will benefit the field as a cover crop and as green manure. At full biomass maturity, plow the legumes into the soil as green manure for the next crop.

For a source of green manure to the field, cut the legumes at full maturity, shred, and spread over the field.

Preventing Soil Erosion while Adding Nutrients to the Soil

The first step in soil management is preventing the loss, or erosion, of soil. Topsoil is particularly vulnerable to erosion if not protected by plants or mulch or by other measures. The soil that remains after the loss of topsoil is usually less productive, which can result in lower yields. The challenge is to protect soil while using the land for food production and other non-food activities.

Soil erosion is caused mainly by wind and water but also by incorrect cultivation practices. Rain and wind dislodge and then carry away soil particles. Where the soil is bare or the vegetation poor, rainwater does not seep into the soil; instead it runs off and carries with it loose topsoil. Sloping land and light soils with low organic matter content are both prone to erosion. Once eroded, the soil is lost forever.

Soil erosion is a problem in regions with little vegetation, particularly in the semi-arid and arid zones. In the humid tropics, erosion was not considered a problem when the land was in its natural state, because the variety of native plants kept the soils covered at all times. Now, people are clearing more land for agricultural purposes, and the situation has changed. Heavy rains coupled with poor soil management of cultivated areas are now common causes of soil erosion in the humid areas.

Water Erosion

Some common forms of water erosion include:

Sheet erosion: a thin top layer of soil is removed from the soil by the impact of rain. With sheet erosion, small heaps of loose material (e.g. grass) amass between fine lines of sand after a rainstorm. This erosion takes place across a whole garden or field.
Rill erosion: water flows over minor depressions on the land's surface and cuts small channels into the soil. The erosion takes place along the length of these channels.
Gully erosion: a gully forms along natural depressions on the soil's surface or on slopes. The head of a gully moves up the slope in the opposite direction of the flow of water. Gullies are symptoms of severe erosion.

Wind Erosion

This occurs mostly on light soils and bare land. High winds cause severe damage. Wind erosion is a common problem in dry and semi-arid areas, as well as in areas that get seasonal rains.

Unlike water which only erodes on slopes, wind can remove soil from flat land as well as from sloping land; it can also transport the soil particles through the air and deposit them far away. Soils vulnerable to wind erosion are dry, loose, light soils with little or no vegetative cover.

Plowing up and down a slope causes soil erosion. To prevent the loss of soils, certain measures must be taken.

These include:

clearing only the land to be cultivated;
planting along a contour and using grassed channels;
establishing windbreaks and bench terraces;
plowing along a contour;
planting cover crops and mulching.

When clearing land for cultivation, the beneficial effects of certain trees and plants should be considered. Some trees should be left, since they may supply food, medicine, shade or, when they shed their leaves, organic matter.

Feeding the Soil

One of the main goals in growing crops is to make the soil fertile and well structured, so a wide range of useful crops can grow and produce well. In order to grow, plants require nutrients that are present in organic matter, such as nitrogen, calcium and phosphorus, as well as minerals and trace elements.

If the natural fertility or structure of the soil is poor, it must be continuously "fed" with organic matter, such as leaves and manure, in order to improve its productivity and water-holding capacity. As organic matter decomposes, it becomes food for plants. It also improves soil structure by loosening heavy clay and binding sandy soil.

Feeding the soil with organic matter is especially important in the early years of cultivating the land. Organic matter (i.e. waste from plants and livestock) can be collected and buried in the soil, where it will decompose. The organic matter also can be used to make compost, which can be applied to the soil to enrich its fertility.

The roots of legumes contain nitrogen-fixing bacteria. Therefore, intercropping or rotating legumes with other crops helps maintain or improve the nitrogen content of the soil, and this enhances the growth of other plants.

Healthy plants yield more and are better protected from insects and disease. The application of organic matter, such as compost, animal manure, green manure and soil from anthills, improves soil structure and adds nutrients to the soil.

Long-Term Soil Management

The ideal way to protect and feed the soil is to apply organic matter or compost regularly and to keep the soil covered with plants. A multilayer cropping system in which a mixture of trees and other plants with different maturity times are grown together will protect the soil and recycle nutrients. Leguminous plants such as cowpeas, groundnuts and beans are particularly useful in providing continuous nutrients for crops.

Apply Organic Matter to Soil to Improve the Crop

Plants can contain up to 90 percent water. The water is absorbed mainly through the root system of the plant. With the water, plant nutrients are absorbed. Healthy roots need air (aeration) for development. Excess water in the soil prevents air from penetrating and damages a plant's roots. Water management is therefore extremely important in regions with good water resources as well as in those where water is scarce.

The water-holding capacity of soil varies according to soil type. Soil with a high content of organic matter has better aeration, better structure and better water-holding capacity. Heavy, sticky soils are too dense to allow air in and water out, so roots cannot breathe and plants can have growth problems. When this kind of soil dries out, it sets like cement, and water takes a long time to soak into it. On the other hand, sandy, coarse-grained soils are too loose to hold water before it drains away. In this kind of soil, without a regular external water supply, a plant's roots cannot find enough water for growth. Regular application of organic matter will improve the ability of both these kinds of soil to hold and release enough water and air. During land preparation for planting, organic materials such as animal manure or compost should be applied to the land such that they are well incorporated into the soil.

Iturriak

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