Soil Quality

Combustion of coal for production of electricity in the United States often requires the removal of SO 2 produced in the flue gas in order to meet clean air regulations. Some scrubbing technologies lead to the production of large amounts of flue gas desulfurization (FGD)-gypsum. Gypsum is a soluble source of the plant nutrients Ca and S and can also improve the physical and chemical properties of soils. However, there are few reports on the use of FGD-gypsum for enhancement of crop growth or soil quality in agriculture. FGD products, used as S fertilizers, were applied at a rate of 30 lbs S/acre to an agricultural soil (Wooster silt loam, Typic Fragiudalf). Corn (Zea mays) grain yield was statistically (P ≤ 0.05) increased by 18.3% in 2002 and 6.6% in 2003 as compared to a no-treatment control. Based upon measurements of soil chemical properties, the quality of a Blount soil (Aeric Epiaqualf) in Ohio was improved by application of 1,500 to 3,000 lbs of FGD-gypsum/acre. Water-soluble Ca and S were increased to a depth of 80 cm and exchangeable Al was decreased between 10 and 40 cm depth. Preliminary results of an economic analysis suggested that a gypsum/no-tillage crop production system had economic advantages compared to a no gypsum/conventional tillage system for soybean production.

This paper considers features underlying conservation-effective agricultural systems' impacts, because they can explain present successes, suggest guidelines for future initiatives, and indicate criteria for judging their effectiveness. Once farmers have made the transition in awareness, thinking and practice of Conservation Agriculture (CA), positive benefits which attract farmers include savings in time, labour, energy and expenditure, with increased productivity and profit

The maintenance of soil health and productivity is a central aim of sustainable agriculture. Arbuscular mycorrhizal fungi (AMF) are soil biota fundamental for soil fertility and plant nutrition, which may be used in the evaluation of the impact of agronomic practices on soil quality. In the present study we evaluated the influence of three different land uses on AMF populations and correlated glomalin-related soil protein (GRSP) content with AMF biomass parameters, such as spore density and biovolume. Among the differently managed sites -maize monoculture, grassland and poplar grove -maize soil showed the lowest AMF spore number and GRSP content. The same morphological taxa were found in the three sites, except for one additional morphotype in poplar grove. A good correlation between GRSP and spore biovolume was found, suggesting that GRSP may represent a useful biochemical parameter for the assessment of biological soil fertility in sustainable agriculture. #

Phuleli Canal (Sindh) Pakistan is the main source of irrigation water for lower Sindh. However, its quality has
been deteriorated by the addition of industrial effluents and city wastes discharged directly or indirectly into canal when it
passes through Hyderabad city. For monitoring the effect of this canal water on soil quality of the command area, the
present study was designed to evaluate the seasonal variability of trace metals including Cu, Fe, Zn and Mn in the
cultivated soil area. The soil samples were collected from different seven sites (reduced distance, RD = 304.8 m) RD-0,
RD-30, RD-50, RD-70, RD-90, RD-110 and RD-130) in four seasons (summer, autumn, winter, and spring) and analysed
for Cu, Fe, Zn and Mn contents. Then, the obtained results were compared with the maximum permissible values of FAO
for agriculture/crop production. Results showed that the Zn contents in soil samples was relatively higher than FAO
permissible limits during winter in all soil layers and all sites mostly at upper reach sites of Phuleli Command area. While,
the Fe content in soil at all depths was found higher during winter, autumn and spring. Whereas, in summer season it
was relatively more in upper soil layers near mid to down reach sites and were not within the permissible limits of FAO.
Same was true with Cu and Mn which were also not within the permissible limits of FAO for crop production. So, it was
inferred that almost of the locations trace elements in soils found higher under Phuleli Canal Command area were mainly
produced from various pollution sources viz, industrial and municipal liquid effluents.

In Bangladesh, almost 53% of the coastal areas are severely affected by salinity which is the major cause for unfavorable environment and hydrological conditions. This unfavorable condition in turn restricts the usual and normal crop production. Batiaghata, an upazila of Khulna in Bangladesh is one of the coastal areas which are severely affected by salinity. This research was conducted to evaluate the soil salinity level (EC value) in 2018 and to compare that collected data with the data obtained by SRDI in 2008 from the similar sites. It was found that the sampling sites that had been urbanized in 2018 showed lesser EC value than 2008 while sampling sites where rice cultivation had been practiced since 2008, showed an increment in EC value.

Ensuring acceptance of dedicated biomass feedstocks by landowners, agricultural communities, environmental and public interest groups, requires that the environmental benefits, concerns, and risks associated with their production be quantified. Establishment and management measures to benefit soil and water quality are being identified by ongoing research. Field studies are showing that nutrients are retained within the rooting zone of dedicated feedstocks, subsurface herbicide transport does not occur, and off-site chemical transport is minimal compared with traditional agricultural crops. The amounts and timing of fertilizer application were critical to minimizing off- site transport of nutrients. Maintaining soil cover decreased runoff, sediment losses, and nutrient transport compared with traditional agricultural crops. Conversion of traditional croplands to biomass and no-till crop production improved soil quality and soil carbon storage. Subsurface nutrient losses were less fr...

Cropping systems in Western Australia (WA) are strongly dominated by cereals (wheat, barley and oaten hay) and are inextricably linked to soil quality and moisture supply. So a major research challenge is to devise cropping systems that improve soil health and maximise water-use efficiency. For a profitable and sustainable production system there is a clear need for ‘break crop’ to provide a pest, disease and weed break, conserve soil moisture; adding soil organic matter and nutrients and to help alleviate soil physical and structural problems. This review article demonstrates the role of ‘break crops’ and/or of ‘crop rotations’ in providing potential soil quality benefits for profitable and sustainable crop production systems.

Soil microbial biomass plays important roles in nutrient cycling, plant-pathogen suppression, decomposition of residues and degradation of pollutants; therefore, it is often regarded as a good indicator of soil quality. We reviewed more than a hundred studies in which microbial biomass-C (MB-C), microbial quotient (MB-C/TSOC, total soil organic carbon) and metabolic quotient (qCO 2 ) were evaluated with the objective of understanding MB-C responses to various soil-management practices in Brazilian ecosystems. These practices included tillage systems, crop rotations, pastures, organic farming, inputs of industrial residues and urban sewage sludge, applications of agrochemicals and burning. With a metaanalysis of 233 data points, we confirmed the benefits of no-tillage in preserving MB-C and reducing qCO 2 in comparison to conventional tillage. A large number of studies described increases in MB-C and MB-C/TSOC due to permanent organic farming, also benefits from crop rotations particularly with several species involved, whereas application of agrochemicals and burning severely disturbed soil microbial communities. The MB-C decreased in overgrazed pastures, but increased in pastures rotated with wellmanaged crops. Responses of MB-C, MB-C/TSOC and qCO 2 to amendment with organic industrial residues varied with residue type, dose applied and soil texture. In conclusion, MB-C and related parameters were, indeed, useful indicators of soil quality in various Brazilian ecosystems. However, direct relationships between MB-C and nutrient-cycling dynamics, microbial diversity and functionality are still unclear. Further studies are needed to develop strategies to maximize beneficial effects of microbial communities on soil fertility and crop productivity.

Soil organic matter (SOM) is known to play a major role in soil fertility due to its influence on physical, chemical and biological properties of soil; and it is closely related to particle size distribution. The ratio of SOM (g kg À1 ) to clay + silt content (g kg À1 ) was evaluated as an indicator of soil quality for barley (Hordeum vulgare) grain yield, reflecting N availability and soil physical conditions to which crop development is sensitive. Thirty-eight sites in the semiarid Pampa region of Argentina with a wide range of SOM and texture were evaluated for malting barley yield during three growing seasons. In control plots, 51% of grain yield could be explained by this indicator. The threshold value between high and low N-fertilization response was 4.4. Better yield prediction to almost 68% was achieved by combining the SOM to clay + silt indicator with initial nitrate content of the soil at seeding. This combined indicator was also able to explain a high proportion of water use efficiency, particularly in the early growth stages. The ratio of SOM to clay + silt content provided a better tool for estimating grain yield than nutrient availability or SOM alone. #

Bio-oil and bio-char were produced from corn cobs and corn stover (stalks, leaves and husks) by fast pyrolysis using a pilot scale fluidized bed reactor. Yields of 60% (mass/mass) bio-oil (high heating values are w20 MJ kg À1 , and densities >1.0 Mg m À3) were realized from both corn cobs and from corn stover. The high energy density of bio-oil, w20-32 times on a per unit volume basis over the raw corn residues, offers potentially significant savings in transportation costs particularly for a distributed ''farm scale'' bio-refinery system. Biochar yield was 18.9% and 17.0% (mass/mass) from corn cobs and corn stover, respectively. Deploying the bio-char co-product, which contains most of the nutrient minerals from the corn residues, as well as a significant amount of carbon, to the land can enhance soil quality, sequester carbon, and alleviate environmental problems associated with removal of crop residues from fields.

Conventional agriculture has had major environmental impacts, in particular with respect to soil degradation. Soil structure, fertility, microbial and faunal biodiversity have declined, and root diseases are common unless genetic resistance, soil fumigation and/or seed treatments are used. Primarily for environmental reasons and increasing demands for safe and healthy food from the public, farmers have switched over to organic production at an increasing rate. During a transition period of about 5 years, organic farmers may face problems with yield losses and pest or disease problems. However, in well-managed, long-term organic farms, soilborne diseases need not be a problem. Several studies in which disease severity was compared in organic and conventional farming systems (or with soils from those systems) showed that root diseases are generally less severe in organically than conventionally managed soils. The reasons for reduced root disease severity have seldom been investigated, although relationships with nitrogen supply or microbial diversity have sometimes been found. Crop protection in organic farming is generally not directed at controlling particular pathogens or pests but at management of the environment so that plants are able to withstand potential attacks. Resistant cultivars adapted to the local conditions are in demand among organic farmers. However, the main practices that contribute to disease control are long, balanced rotations, organic amendments and reduced tillage, all geared towards maintenance of the soil organic matter content and fertility. Organic farmers can make use of biological control agents and natural toxic compounds in plant extracts. However, these practices are methods of last resort. A P 0 3 0 2 9 I n t e g r a t e d r o o t d i s e a s e m a n a g e me n t i n o r g a n i c f a r m i n g A . H . C . v a n B r u g g e n a n d A. J . T e r m o r s h u i z e n Additional keywords: conventional agriculture, organic agriculture, soil health, soil quality.

BIJLAGE I. BEKNOPT OVERZICHT VAN DE MODELLEN STOFSTROMEN EN STONE 55 Overzicht van de stikstofcyclus in het model STONE 55 Overzicht van het model Stofstromenmodel 56 BIJLAGE II. OPTIES VOOR HET KWANTIFICEREN VAN STIKSTOFPLAFONDS 59 BIJLAGE III. BETROUWBAARHEID VAN DE BEREKENDE STIKSTOFPLAFONDS 63 Kwalitatieve analyse 63 Kwantitatieve analyse 65 BIJLAGE IV. GEWASEMISSIES 67 Factoren die het compenstatiepunt voor NH 3 -emissie door gewassen bepalen 69

As key 'ecosystem engineers', earthworms improve mineralization of organic matter, plant growth, soil quality, and are an important component of many terrestrial food webs. Under appropriate conditions, they are therefore likely to accelerate the restoration of soil ecosystem function after mining.

Cserháti Sándort -a növénytermesztéstan tanárát, a tudós szakírót, a belterjes (intenzív) gazdálkodás szószólóját, az első Országos Kísérleti Állomás ve ze tő jét -mindenkor a legkiválóbbak között tartották számon. Tudományos mű helyében, amelyet Cserháti iskolának nevezünk, példáját és tanításait ma gá nak vallva számos kiváló tudós és szakember nőtt fel azokhoz a feladatokhoz, ame lyeket a tudomány kihívásai és a gyakorlat el várásai felkínáltak. Cserháti újat hozott abban is, hogy nem csak keményen bírálta a hi ányos talajmunkát vég zőket, s a rossz művelés okán alacsony terméseket, hanem hasznos tanácsokkal is szolgált. Őt tekintjük a talajállapot javító okszerű mélyművelés első magyar szószólójának, noha a tömörödés valódi veszélyét és számos kö vet kez ményét nem állt módjában felismerni. Cserháti Általános növénytermelés c. köny vében együtt tárgyalta a műveléssel változtatható, illetve nem módo sít ható minőség té nye zőket. A műveléssel változtatható talajminőség tényezők Cser háti nyomán a humusztar-ta lom, a tömődöttség, a talajnedvesség, a struktúra, a légjárhatóság, a talaj fel melegedése tavasszal, a talaj felülete, a talaj bebo rítottsága, a beéredés, és a gyommentesség. E ténye zők többsége napjainkig időt állónak bizonyult.

Raw sewage is widely used on agricultural soils in urban areas of developing countries to meet water shortages. Although it is a good source of plant nutrients, such sewage also increases the heavy metal load to soils, which may impact the food chain. Management options for sewage contaminated soils includes addition of nontoxic compounds such as lime, calcium sulfate and organic matter, which form insoluble metal complexes, thus reducing metal phytoavailability to plants. In this paper we review the variation in irrigation quality of sewage at different sites and its impact on the quality of soils and vegetables. Although quality of sewage was highly variable at source, yet the effluent from food industries was relatively safe for irrigation. In comparison effluent samples collected from textile, dyeing, calendaring, steel industry, hospitals and clinical laboratories, foundries and tanneries were hazardous with respect to soluble salts, sodium adsorption ratio and heavy metals like zinc, copper, iron, manganese, nickel, cobalt and cadmium. The sewage quality in main drains was better than that at the industry outlet, but was still not safe for irrigation. In general, higher accumulation of metals in fruits and vegetable roots was recorded compared to that in plant leaves. Edible parts of vegetables (fruits and/or leaves) accumulated metals more than the permissible limits despite the soils contained ammonium bicarbonate diethylenetriaminepentaacetic acid extractable metals within a safe range. In either case further scientific investigations are needed to ensure safe management strategies. Cadmium appeared to be the most threatening metal especially in leafy vegetables. It is advisable to avoid leafy vegetables cultivation in sewage irrigated areas everywhere to restrict its entry into food chain. . 2010. Disposal and use of sewage on agricultural lands in Pakistan: A review. Pedosphere. 20(1): 23-34.

In the last centuries, the need for tillage was to provide suitable soil conditions for plant growth (crop-focusing tillage). During the last decades, traditional goals of soil tillage have really been improved considering environmental consequences (environment-focusing tillage). In the next decade a new task is stressed, that is mitigating the climate induced losses (climate-focusing tillage). New challenges for the future are prevention of tillage-induced soil quality deterioration, and to reduce climate induced damages by the use of environmentally-sound adaptable tillage. In the adaptable tillage program ten important steps are suggested, namely: Risk assessment in the fields. (2) Prevention of tillage induced defects affecting climate stresses. (3) Maintaining an optimal soil physical and biological state and fertility. (4) Use soil structure conservation methods in any seasons. (5) Mulch the surface at least in summer. (6) Improve soil loading capacity connected with carbon conservation. (7) Utilize stubble residues rationally. (8) Maintain an optimal water management in soils by the soil state improving. (9) Create small water-loss surface at tillage operations. (10) Improve a harmony between soil disturbance and environmental requirements. Birkás M., Jolánkai M., Schmidt R. 2008. Environmentally-sound adaptable tillage -Solutions from Hungary. 1 st Scientific Agronomic Days ,[13][14] Nitra, Slovakia. Proc. of reviewed sci. papers (Eds. Hrubá, M., et al.),

We compared the effect of organic and conventional farming practices on soil microbial dynamics in West Java, Indonesia. A secondary forest was included to obtain natural reference values. On the organic farms, soil fertility is maintained mainly with composted organic matter in contrast to conventional farmers who combine fresh manure and chemical fertilizers, and typically apply large amounts of pesticides. Parameters measured were dehydrogenase, ␤-glucosidase, acid phosphomonoesterase and ␤-glucosaminidase activity, microbial biomass C (MBC) and microbial community composition by phospholipid fatty acid analysis. A strong negative impact of intensive chemical fertilizer and pesticide use on soil enzyme activities was demonstrated. Dehydrogenase and ␤-glucosidase activities were correlated with soil organic matter content and pH. ␤-glucosidase activity under organic management approached that under forest, while MBC and dehydrogenase activity remained higher under forest. The composition of the soil microbial community strongly differed between forest and cultivated soil, a clear difference in composition was also observed between conventional and organic farming. Dehydrogenase activity and C16:1ω5c, marker fatty acid for arbuscular mycorrhizal fungi, appeared to be particularly suited as indicators of the impact of management on soil quality and on the soil microbial community.

Crop residue mulching combined with zero tillage and crop rotation, known as conservation agriculture (CA), is being promoted as an alternative system to revert soil degradation in maize-based farming in the central highlands of Mexico. The goal of this paper was to determine the effects of CA vs. conventional tillage systems on soil quality, with a special focus on the role of earthworms in affecting the soil structure morphology, and on crop yield. For the conventional tillage system, the effect of crop residue retention (CONV + RES) was also compared to the conventional farmers’ practice (residues removed; CONV). CA resulted in four times higher earthworm abundance when compared to CONV. Residue retention per se (CONV + RES) did not favor earthworm abundance. In all cases the earthworm community was dominated by exotic species. CA increased total N and soil organic C concentrations relative to CONV, but only at 0–5 cm soil depth. Nevertheless, the more pronounced vertical stratification of soil organic carbon content under CA favored soil surface aggregation and aggregate stability as expressed by the aggregate mean weight diameter after dry sieving (MWDds = 2.6 mm for CA and 1.6 mm for CONV) and wet sieving (MWDws = 0.9 mm and 0.6 mm, respectively). Also, CA improved topsoil water stable macroaggregation (WSA = 415 mg g−1) when compared to CONV (251 mg g−1). Residue retention within conventional tillage (CONV + RES) led to small increases in topsoil aggregate stability (i.e. MWDds and WSA). Soil structural improvements were accompanied by a higher direct surface water infiltration. Micromorphological analysis of thin sections indicated a loose and highly biogenic soil microstructure in CA, whereas CONV was characterized by a physicogenic microstructure, despite similar soil bulk densities (SBD). SBD is thus a poor indicator of soil physical quality when comparing different tillage systems. Redundancy analysis illustrated that CA resulted in improvement in most parameters related to soil quality, especially at the soil surface, but significant yield increases were recorded only in 2004. CONV + RES lead to marginal improvements in soil quality with no yield increases.

While water erosion has been the focus of past research in the Andes, former studies show that soil erosion could also be related to the methods used in cultivating the fields. The main objective of the present study was to assess (i) tillage erosion caused by the traditional animal-powered “yunta” or ard plough in the Andes and the factors controlling the process and (ii) the implications for soil conservation. Erosion rates were experimentally measured on 27 sites, having slopes from ca. 0% to 60% and soils ranging from Andosols to ...

Відповідно до вимог системного аналізу розгляд функціонування калійної системи, з одного боку, ґрунтується на аксіомі її цілісності, з іншого, - вирішення цього завдання неможливе без детального вивчення і характеристики її елементів, структури і ієрархії, системоутворювальних відносин, визначення їх просторових меж.

This paper discusses the influence of N resources (fertilizer, legume, soil) on sustainable agriculture in temperate/boreal ecosystems (exemplified by the Canadian prairies), and in the humid, subhumid and semi-arid tropic (exemplified by southeast Asia and central and south America). A sustainable agricultural system is one that is economically viable, provides safe, nutritious food, and. conserves or enhances the environment. Consequently, we discuss the impact of N on crop yields, nitrogen use efficiency (NUE), food quality, environmental quality and on socioeconomic factors. Considerably more long-term research has been conducted in the temperate regions, consequently this was where most information was available. However, the principles governing the behaviour of N are very similar in all ecosystems. It is mainly the rates of nutrient cycling and the socioeconomic constraints that differ. Legumes and N fertilizers, used in a responsible manner, will increase crop production, provide quality food, increase net returns, reduce risk of monetary loss, improve soil quality, and reduce N loss via leaching and gaseous means. The key to sustainable management of N is to synchronize N supply with N use by the crop. Because societies in most temperate ecosystems are more affluent they are better positioned to encourage adoption of management techniques that promote sustainability. In contrast, most producers in the tropics are, subsistence farmers; consequentIy, their immediate goal is economic survival, not preservation of the environment.

Soils in semi-arid Mediterranean areas are generally characterized by low organic matter content and are subjected to progressive degradation and deterioration of workability. Because de-oiled two-phase olive mill waste (DW) contains an important level of organic matter content, its recycling as organic amendment or fertilizer may be an alternative for its disposal that also improves soil quality and productivity. A ten-year field study was conducted to evaluate the long-term sustainability of raw deoiled two-phase olive mill waste (DW) disposal as a soil amendment on an olive grove in Elvas, Portugal. The soil was amended with DW at rates of 0, 27, and 54 Mg ha À1 , dry weight equivalent, for eight years, with cumulative and residual effects being assessed in the last year and two years after the last application. The DW amendments significantly increased the olive yield only in the residual year at the 27 Mg ha À1 application rate. Long-term applications of DW to soil led to positive cumulative and residual effects on the soil's chemical (total organic carbon and its humified fractions, total N, available P, and K), properties. Simultaneously, dehydrogenase, urease, b-glucosidase, alkaline phosphatase, and arylsulfatase activities increased even at the higher DW application rates. Electrical conductivity rose significantly with DW application, especially in the residual year, ranging from 0.513 dS m À1 for the unamended soil to 1.89 dS m À1 at the 54 Mg ha À1 application rate. The addition of raw DW to an olive grove may be considered to be a good strategy for recycling this waste, converting it into a resource that could be used for a long time as organic amendment without negatively affecting yield, while improving many soil properties. However, the greatest concern regarding the long-term use of DW is the risk of soil salinity, especially if application rates are greater than 27 Mg ha À1 .

Crop-pasture rotations (CPR) are unusual around the world but have been the predominant cropping system in Uruguay since the 1960s. Uruguay has a temperate sub-humid climate, 80% of its landscape (16 Mha) is climax grasslands C 3 and C 4 species. Beef, wool, and dairy are the main commodities. Crops occupy a portion of the remaining 20% land area, primarily on Argiudolls and Vertisols, rotated with seeded grass and legume pastures. Continuous cropping (CC) with conventional tillage (CT) has proven unsustainable due to decreased soil productivity. Seeded pasture periods increased soil productivity. CPR adoption created less variable inter-annual economic results, but soil degradation remained a major concern during the crop cycle using CT. Farmers and technicians became interested in no-till (NT) to reduce erosion and production cost. Currently, approximately 52% of crop producing farms and 25% of dairy farms have adopted NT. This paper synthesizes research results (mainly from long-term experiments) contrasting CC versus CPR with CT (1960CT ( -1990 and NT (from 1990). Soil erosion was reduced more than six times with NT in CC, and almost three times in CPR compared with CC using CT; but combining the use of CPR and NT resulted in the same low erosion rate as under natural pasture. The transition from CT to NT is not always easy. The time between herbicide application to pasture and planting of the first crop of the rotation crop cycle with NT is a critical transition factor to optimize N and water availability, and soil tilth. Chiseling or paraplowing can alleviate plow-pans inherited by NT from previous CT; but higher soil strength at the soil surface under NT contributes to better forage utilization under grazing. Soil organic carbon (SOC) content in CC decreased with CT, and was maintained with NT only if grain was harvested. In CC systems with harvested forage, SOC decreased even with NT. CPR with NT maintained or increased the original SOC content. The paper concludes with a discussion on the relative sustainability of CC versus CPR with NT. Both are sustainable from the soil quality and productivity standpoints. But compared with CC, CPR is a more economically and climatically buffered system, due to higher diversity. Also, CPR systems are more environmentally sustainable since fuel and agrochemicals usage is reduced approximately 50%.

The sustainability of shifting cultivation systems and their impact on soil quality continues to be debated, and although a growing body of literature shows a limited impact on, e.g. soil carbon stocks, shifting cultivation still has a reputation as detrimental to the environment. We wished to compare soil erosion from three land use types in a shifting cultivation system, namely upland rice, pepper gardens and native forest. We used two sample sites within the humid tropical lowland zone in Sarawak, Malaysia. Both areas had steep slopes between 258 and 508, and were characterised by a mosaic land use of native forest, secondary re-growth, upland rice fields and pepper gardens. Soil samples were collected to 90 cm depth from all three land use types, and analysed for various chemical parameters, including texture, total organic matter and 137 Cs content. 137 Cs is a radioactive isotope derived from nuclear fallout, and was used to estimate the retention of topsoil in the profiles. Soil chemical parameters in upland rice fields, such as extractable cations, pH and conductivity, indicated limited soil transportation downslope, and depletion of cations from upslope samples are most likely caused by leaching and losses via ashes after clearing and burning. The position on slope had no significant effect on soil texture, carbon or P content, indicating very limited physical movement of soil downslope. A soil carbon inventory to 90 cm depth on the three land uses only showed a higher carbon concentration in the top 5 cm of forest and upland rice plots. When corrected for soil density, there was no effect of land use on the carbon inventory. Moreover, the carbon content in the top 30 cm contributed <50% of the total carbon inventory, hence even significant effects of land use on carbon content in the upper soil layers, are unlikely to change the carbon inventory dramatically. 137 Cs content in the soil profile indicated largest retention of original topsoil in the native forest plots, and a loss of 18 and 35% of topsoil from upland rice and pepper gardens, respectively, over the past 40 years. When comparing to 30 cm depth, soil loss was 30% from both upland rice and pepper fields. Low 137 Cs activity in deeper soil layers rendered a total profile inventory impossible. It is concluded that shifting cultivation of upland rice in the current system is not leading to degradation of soil chemical and physical quality. The soil carbon inventory is not affected by land use in this analysis, due to the contribution from the deeper soil layers. #

We describe a practical methodology to rapidly assess the soil quality and crop health of vineyard systems using simple indicators chosen, applied and interpreted jointly by farmers and researchers. Field measurements are made on agroecosystem properties that reflect soil quality and plant health. As measurements are based on the same indicators, the results are comparable and allow farmers to monitor the evolution of the same agroecosystem along a timeline, or make comparisons between farms in various transitional stages. Once the indicators are applied, each farmer can visualize in an amoeba diagram the conditions of his or her farm, noticing which of the soil or plant attributes are sufficient or deficient compared to a pre-established threshold. By applying the methodology simultaneously to several farms it is possible to visualize which farms exhibit low or high values of sustainability. Although the indicators reported here are specific to vineyards in northern California, with some modifications, this methodology is applicable to a broad range of agroecosystems in various eco-regions.

Soil algae can perform important services for agro-ecosystems and functions as a bioindicator for soil quality. Communities of topsoil algae were studied (species composition and counts) in four different agro-ecosystems in relation to different land uses, including tillage. The chosen agro-ecosystems were an intensively-cultivated corn (Zea mays L.) field, a vineyard, a pasture and a field abandoned for 12 years. In all, 92 algal species were identified in the different ecosystems, which were sampled twice (March and May). In 2001 the main algal species were Cyanophyceae, Chlamydophyceae, and Chlorophyceae. The greatest species richness of algal species was recorded in the pasture, followed by the abandoned field, the corn field and the vineyard. Using a dilution method on solid media to count the algae enabled the distinction and separate quantification of cyanophytes, diatoms and greenish algae (cholorophytes (CH) + xanthophytes (X) + eustigmatophytes (E)). This last group of greenish algae dominated at all four sites, together with cyanophytes in the pasture and the abandoned field, whereas cyanophytes were almost absent in the vineyard. The highest mean abundance of algal cells in the 0-2 cm soil layer was found in the abandoned field and in the pasture, while it was lower in the corn field and in the vineyard. The undisturbed sites (abandoned field and, to some extent, pasture) were also characterised by a greater diversity of algae. Disturbance (tillage and use of pesticides) seemed to have a strong effect on both the composition and the density of the algal communities. Cyanophytes (Calothrix sp., Cylindrospermum sp., Pseudoanabaena sp., Scytonema sp. and Thricormus sp.) seemed to be particularly sensitive to disturbance. Heavy metals residues in the soil, especially Cu (linked to fungicide sprays, used particularly in vineyards), may be a factor affecting the abundance of cyanobacteria. It would be reasonable to conclude that the structure of soil algal communities is affected more by soil use rather than by physico-chemical soil parameters. Cyanobacteria showed the most evident response in the different agro-ecosystems, and therefore seem to be the most suitable group to consider as a soil bioindicator of land use. #

El INIBAP (Red Internacional para el Mejoramiento del Banano y el Plátano) y MUSALAC (Red de Investigación y Desarrollo de Plátano y Banano para ALC), con el financiamiento de FONTAGRO (Fondo Regional de Tecnología Agropecuaria) esta promoviendo una iniciativa en América Latina y el Caribe, que ha permitido una serie de acciones orientadas a proveer un mayor entendimiento de la salud y la calidad de los suelos, con el propósito de recuperar o mantener la productividad de las plantaciones bananeras. Uno de los productos más importantes de esta iniciativa regional es el desarrollo de una guía para el diagnóstico de la calidad y la salud del suelo. La guía fue desarrollada con la identificación y estudio de 22 indicadores principales (68 diferentes variables) que cubrían componentes físico-químicos del suelo así como parámetros microbiológicos. La investigación se hizo en 42 fincas de cuatro países de ALC. Para verificar la conveniencia y funcionalidad de los diferentes indicadores, se probó la guía en fincas con diferentes grados de producción y manejo agronómico (fincas de exportación, producción convencional y orgánica, fincas para mercado local, pequeñas, medianas y grandes). A su vez cada finca se caracterizó en sitios de producción buena, regular y mala. Se explica el proceso y la metodología establecida para el desarrollo de la guía (selección final de indicadores y construcción del índice). La guía estará disponible en tres idiomas.

The unsaturated soil hydraulic functions involving the soil-water retention curve (SWRC) and the hydraulic conductivity provide useful integrated indices of soil quality. Existing and newly devised methods were used to formulate pedotransfer functions (PTFs) that predict the SWRC from readily available soil data. The PTFs were calibrated using a large soils database from Hungary. The database contains measured soil-water retention data, the dry bulk density, sand, silt and clay percentages, and the organic matter content of 305 soil layers from some 80 soil profiles. A three-parameter van Genuchten type function was fitted to the measured retention data to obtain SWRC parameters for each soil sample in the database. Using a quasi-random procedure, the database was divided into ''evaluation'' (EVAL) and ''test'' (TEST) parts containing 225 and 80 soil samples, respectively. Linear PTFs for the SWRC parameters were calculated for the EVAL database. The PTFs used for this purpose particle-size percentages, dry bulk density, organic matter content, and the sand/silt ratio, as well as simple transforms (such as logarithms and products) of these independent variables. Of the various independent variables, the eight most significant were used to calculate the different PTFs. A nonlinear (NL) predictive method was obtained by substituting the linear PTFs directly into the SWRC equation, and subsequently adjusting the PTF parameters to all retention data of the EVAL database. The estimation error (SSQ) and efficiency (EE) were used to compare the effectiveness of the linear and nonlinearly adjusted PTFs. We found that EE of the EVAL and the TEST databases increased by 4 and 7%, respectively, using the second nonlinear optimization approach.

... labile P sources (Bolan, 1991 and Hernández et al., 2000), but other studies demonstrated that mycorrhizal plants obtained P from normally unavailable sources of Pi and Po (Bolan et al., 1987, Jayachandran et al., 1989, Jayachandran et al., 1992, Koide and Kabir, 2000 and ...

Soil quality management helps to maintain biological productivity; air and water quality; and human habitation and health. As improper land management can deteriorate soil function, the evaluation of soil quality for different land use is necessary. To evaluate soil quality for different land use types in the Panchase area, soil quality index was computed on the basis of the soil management assessment framework. Protected forest has the highest soil quality index (0.95) followed by community forest (0.91), pasture (0.88), khet (0.81), and bari (0.79). Available phosphorus and soil organic carbon play major roles in making significant differences in the SQI among the different land use types. Less anthropogenic impact and vegetation in forest land result in better soil quality, whereas attempts to increase productivity in cultivated land degrade the soil quality. The proper application of fertilizer and giving priority to organic farming is recommended to improve soil quality.