Arable Cultivation Research Articles

Response of soil microbial community composition and function to a bottomland forest restoration intensity gradient

Terrestrial ecosystems are globally under threat of loss or degradation. To compensate for the impacts incurred by loss and/or degradation, efforts to restore ecosystems are being undertaken. These efforts often focus on restoring the aboveground plant community with the expectation that the belowground microbial community will follow suit. This ‘Field of Dreams’ expectation – if you build it, they will come – makes untested assumptions about how microbial communities and their functions will respond to aboveground-focused restoration. To determine if restoration of aboveground plant communities equates to restoration of belowground microbial communities, we assessed the effects of four forest restoration treatments – varying in intensity from unmanaged to interplanting tree species – on microbial (i.e. prokaryotic and fungal) community composition and function (i.e. catabolic profiles and extracellular enzyme activities). Additionally, effects of the restoration treatments were compared to both degraded (i.e. active arable cultivation) and target endpoint communities (i.e. remnant bottomland forest) to determine the trajectory of intensifying aboveground restoration efforts on microbial communities. Approximately 16 years after the initiation of the restoration treatments, prokaryotic and fungal community composition, and microbial function in the four restoration treatments were intermediate to the endpoint communities. Surprisingly, intensification of aboveground restoration efforts led to few differences among the four restoration treatments and increasing intensification did not consistently lead to microbial communities with greater similarity in composition and function to the target remnant forest communities. Together these results suggest that belowground microbial community composition and function will respond little to, or will lag markedly behind, intensifying aboveground restoration efforts. Reliance on a ‘Field of Dreams’ approach, even if you build it better, may still lead to belowground microbial communities that remain uncoupled from aboveground communities. Importantly, our findings suggest that restoring aboveground vegetation may not lead to the intended restoration of belowground microbial communities and the ecosystem processes they mediate.

Centralisation and long-term change in farming regimes: Comparing agricultural practices in Neolithic and Iron Age south-west Germany

This study uses two novel archaeobotanical techniques – crop carbon and nitrogen isotope analysis and functional weed ecology – to determine directly how the intensity of agricultural practice changed from the Neolithic to the Early Iron Age in south-west Germany, with the emergence of fortified hilltop settlements (Fürstensitze or chiefly seats) regarded as the first urban centres in central Europe. The crop isotope and functional weed ecological evidence suggest that surplus cereal production in the Early Iron Age was achieved through sustained use of manure combined with expansion in arable cultivation, both developments that are connected with more widespread use of animal traction. The increased scale of cultivation is broadly apparent across rural as well as fortified hilltop centres in the Early Iron Age, and considerable variability in manuring intensity is consistent with agricultural decision-making at a local level rather than centralised control. Additionally, the more intensive manuring of hulled six-row barley, used in beer production, demonstrates that the political importance of drinking and feasting in Early Iron Age society was reflected in crop husbandry practices. In terms of animal husbandry, faunal isotope data reveal a radical decrease in forest cover, potentially reflecting an expansion in the scale of herding accompanying that of arable cultivation. Site-specific patterning points to a range of herding strategies, from specialised herding of cattle at the Heuneburg to generalised patterns of livestock management at rural sites.

Carbon storage and soil property changes following afforestation in mountain ecosystems of the Western Rhodopes, Bulgaria

Abstract: Land-use changes and afforestation activities are widely recognized as possible measures for mitigating climate change through carbon sequestration. The present study was conducted to evaluate the effect of afforestation on (i) soil physical and chemical properties and soil carbon stocks in four mountain ecosystems and (ii) whole ecosystem carbon storage. The four experimental sites, situated in the Western Rhodope Mountains (Bulgaria) were characterized by typical forest-related land-use conversions. The four sites were a Douglas fir (Pseudotsuga menziesii [Mirb.] Franco) plantation (Rd1) established on former cropland, a mixed black pine (Pinus nigra Arn.) with Scots pine (Pinus sylvestris L.) plantation (Rd2) established on former cropland, a cropland (RdA1) and an abandoned land with uncontrolled extensive grazing (RdA2) historically used as cropland. Soil parameters, i.e., sand content, pH, organic C and N contents, C/N ratio and soil organic carbon (SOC) stocks, were significantly affected by land use and land-use history. Conversion from cropland into forestland significantly reduced soil bulk density and coarse fragments at 0-10 cm depth. Compared with adjacent cropland and abandoned land, soils in coniferous plantations were acidified in their upper layers. Sites Rd2 and RdA2 contained the least SOC owing to the previous long-term arable cultivation (>100 years). Analysis of the ecosystem C stock distribution revealed that most of C in forests was stored in the aboveground tree biomass. Our study confirmed that afforestation of cropland turned the soil into a C sink for the selected mountain region, but showed conflicting results when afforestation occurred on abandoned cropland.

Impacts of land use and infrastructural changes on threatened Little Bustard Tetrax tetrax breeding populations: quantitative assessments using a recently developed spatially explicit dynamic modelling framework

SummaryWith the combination of worldwide landscape changes and the uncertainty about the impact on species abundance and distribution, the value of spatio-temporal modelling tools is increasingly obvious. The Little Bustard Tetrax tetrax breeds on low-intensity arable cultivation and pastoral land and is currently threatened by diverse landscape modifications. The aim of this research was to predict Little Bustard population trends in the face of realistic scenarios of land use and infrastructure changes, applying a recently developed spatially explicit framework, based on the stochastic dynamic methodology (StDM). The application of this approach provided some basis to analyse the responses of breeding populations’ spatial distribution and abundance to the scenarios implemented. Since some of these scenarios represent local and/or regional risks to the viability of Little Bustard breeding populations, the results obtained demonstrate the potential of the proposed framework for landscape planning in the scope of the conservation of this threatened species. This approach also provides a promising baseline to support ecological risk assessments for other species, derived from ecological models with increased predictive power and intuitiveness to decision makers and environmental managers.

The theoretical and methodological direction of the strategy of land reclamation

The ecological-economic strategy of use and protection of remediated land was developed. It consists of four main interconnected stages: preparatory, agrotechnical, agroecological and economic. The preparatory phase ensures that the top layer of arable cultivation of waste land through the introduction of career-technical and chemical meliorations, depending on which branch of the economy continue to be used in this area. It was during this time where money is being spent to conduct geotechnical work associated with the remediation of internal and external dump pits. The agrotechnical phase provides optimization of the properties of ecotopia as the habitat of plants. During this phase, funds are spent on the application of organic (norm not less than 50 t/ha manure), organic-mineral and mineral (about 80 kg/ha d. g) fertilizers. In this case, improved physico-chemical properties of remediated land, increases the level of their fertility, which is reflected in the number of products received. Agroecological stage forms the ecotopia suitability for use in agricultural production. This stage contains the effect and aftereffect of all previous measures aimed at amelioration of the restored lands. During this phase, special attention is paid to the final layout of the surface of the field and introduction of special phyto-reclamation rotations, saturated of perennial leguminous herbs or their mixtures with other herbs, including legumes and does not. For each plot must be restored designing her the only acceptable rotation, the ratio and selection of plant species which should be oriented not only at obtaining a stable, high-quality products, but also on the formation of appropriate environmental conditions that ensure the optimal development of all components of biogeocenosis and their protection. The economic stage is what defines the economic sector, the most appropriate future use of remediated lands. On the basis of long-term monitoring researches, within each region, the methodological guidance and practical recommendations for the rational foundations of socio-ecological and economic use of the reclaimed lands in agricultural production are developed. It is determined the payback period of all costs incurred during reclamation of the site and the territory in general. On the basis of these stages it is proved a strategic direction for the creation and implementation of the dump pits of the mining enterp rises of the steppe Dnieper eight basic models of land restoration. The big attention is paid to the biological stage of recultivation, which is based on the analysis and the account of economical, business and physical – geographical features of a place of mining operations. In this paper it is resulted the list of the basic rocks of Nikopol manganese – ore field from which artificial lands (edaphotopes) are created and the prospective branch of their further use is underlined. The priority trend is taken away to an agricultural production. And, to recultivated plots should be given such possibilities which would allow them to perform the same functions what they realized before destruction of this locality. Methodical development works are offered relative to: price definitions of humus layer before destruction of soil and cost 1 м3 of the restored soil covering; expenses on renewal of productive potential of recultivated lands; definitions of the gross revenue and quantity of production from recultivated lands. Also it is affirmed, that recultivated lands should receive not only economic, but also ecological estimation as this indicator reflects the ecological conditions in the given district and has the big social value. The term «Factor of the ecological well-being» districts and its gradation is entered, allowing to define the period of recoupment of expenses on recultivation of land taking into account the ecological and economical efficiency of the restored area.

Summed radiocarbon probability distributions from cereal grains: arable cultivation proxy or the ‘archaeology of us’? (a reply to Stevens and Fuller 2015)

In response to the critique in this volume (Bishop 2015), Stevens and Fuller (2015) have modified their original interpretation of Late Neolithic subsistence strategies in the British Isles (Stevens and Fuller 2012). This article highlights the key issues that remain with their analysis. It is reiterated that radiocarbon summed probability distributions from cereals are not a suitable proxy for the changing importance of arable cultivation through time.

Variation in the Continuity of Land-Use Patterns through the First Millennium AD in Lowland Britain

AbstractThis paper explores the contribution that palaeoenvironmental evidence, and in particular palynology, is making to our understanding of landscape evolution in Britain during the 1st millenniumAD. This was a period of profound social and economic change including a series of invasions, some associated with a mass folk migration. Archaeologists and historians continue to debate the significance of these events, and palaeoenvironmental evidence is now starting to provide an additional perspective. Key to this has been obtaining pollen sequences, although there remains a need for more evidence from lowland areas, alongside higher resolution sampling and improved dating. It is suggested that although the 1st millenniumADsaw some significant long-term shifts in climate, these are unlikely to have had a significant causal effect on landscape change in lowland areas (both in areas with and without significant Anglo-Saxon immigration). The analysis of pollen data from across Britain shows very marked regional variations in the major land-use types (arable, woodland, improved pasture, and unimproved pasture) throughout the Roman and Early Medieval periods. While Britain ceasing to be part of the Roman empire appears to have led to a decline in the intensity of agriculture, it was the ‘long 8th c.’ (the later 7th to early 9th c.) that saw a more profound change, with a period of investment, innovation, and intensification, including an expansion in arable cultivation.

Did Late Neolithic farming fail or flourish? A Scottish perspective on the evidence for Late Neolithic arable cultivation in the British Isles

This paper critically assesses the recent claim (Stevens and Fuller 2012) that cereal agriculture was abandoned in the Late Neolithic of the British Isles. The Scottish archaeobotanical dataset is considered in detail to test the universal applicability of the model proposed by Stevens and Fuller (2012) and a series of alternative hypotheses are suggested to explain the nature of the current evidence. It is argued that the importance of arable agriculture probably varied on a local as well as a regional scale and that caution should be exercised when attempting to apply unitary models to complex datasets.

Fate of semi-natural grassland in England between 1960 and 2013: A test of national conservation policy

It is well documented that significant losses in semi-natural grassland occurred across Europe during the second half of the twentieth century. However, comparatively few studies have investigated and quantified the fate of large numbers of individual grassland areas. This is important for understanding the causes of decline, and consequently establishing new policies to conserve and restore lost habitats. This study addresses this problem; GIS was used to compare historic survey data collected between 1960 and 1981 with two contemporary spatial datasets of habitats in England. The datasets included the Priority Habitats Inventory 2013 and the Land Cover Map 2007 and this was undertaken for different types of semi-natural grassland across England. Considerable decreases occurred across the different grassland types, with a loss of 47% of studied semi-natural grasslands sites in England over 32–53 years. Of this, the majority of grassland was lost to conversion to agriculturally-improved grassland or arable cultivation, 45% and 43% respectively. Changes to woodland and urban areas were also evident, but on a much smaller scale. Sites receiving statutory protection as a Site of Special Scientific Interest were found to have retained more grassland (91%), compared with non-protected sites (27%), thus highlighting the effectiveness of this aspect of current conservation policy in England, and the need for this to continue in the future.

Restoration of sand grasslands by topsoil removal and self‐greening

AbstractQuestionsIs topsoil removal in combination with year‐round grazing a suitable method to restore and maintain nutrient‐poor open sand grasslands and wet heaths on ex‐arable land? Are there constraints in terms of animal nutrition?LocationPastures on ex‐arable land in pleistocene lowlands of Northwestern Germany, 120–160 m a.s.l.MethodsWe sampled vegetation, soil nutrient status and above‐ground biomass properties in 42 quadrats in a restored sand grassland and wet heath site and ten quadrats in an old sand grassland nearby. Data were analyzed using ordination, ANOVA and a generalized linear model.ResultsSoil phosphorus and nitrogen were significantly reduced by topsoil removal to the level of target communities. A remarkably high number of typical and endangered sand grassland species established, presumably from the seed/spore bank. Compared to old, seasonally grazed sand grassland, higher species diversity could be observed after topsoil removal. Reasons may be the raised pH as a heritage of arable cultivation and the very open vegetation structures enhancing early successional species. Year‐round grazing preserved open vegetation structures, but was not able to fully suppress birch encroachment in early stages of succession.ConclusionsOur study showed that combining topsoil removal, self‐greening via recruitment from the seed/spore bank and subsequent year‐round grazing might be particularly successful approaches for the restoration of endangered sand grasslands and wet heaths on ex‐arable land. However, additional measures might be necessary to prevent undesired shrub encroachment in the first years after topsoil removal. Due to relatively low biomass quantity and quality of sand grasslands even in summer, we propose supplementary feeding in winter or a restriction to seasonal grazing to meet the requirements of animal welfare.

Soil seed-bank composition reveals the land-use history of calcareous grasslands

We compared soil seed banks and vegetation of recent (established on abandoned arable fields) and ancient (continuously managed as pastures at least since 1830) calcareous grasslands if there is any impact of former arable field use. The study was carried out in two regions of Southern Germany with well-preserved dry grassland vegetation: the western Jurassic mountains (Kaltes Feld) and the climatically drier eastern part of Southern Germany (Kallmünz).Total number of species in the seed bank was similar in both regions, but species composition partly differed, reflecting phytogeographical differences between the regions. The total number of emerged seedlings showed a large disparity (5457 compared to 2523 seedlings/m2 in Kaltes Feld and Kallmünz, respectively).Though there were differences in seed bank composition and size, we found a uniform pattern of plant traits (affiliation to phytosociological groups, Raunkiaer plant life-forms and seed longevity), which depended on the age of the grassland.The main conclusion is that seed banks in contemporary calcareous grasslands still reflect the history of former land use – in this case arable cultivation, even though it occurred a long time ago (up to 150 years). Indicators of former arable fields are germinable seeds of weeds which have persisted in the soil to the present. By contrast, weedy species are completely absent from the seed banks of ancient grasslands. Soil seed banks of recent grasslands may be of substantial conservation importance because they may store seeds of rare and endangered weed species such as Kickxia spuria, Silene noctiflora and Stachys annua, the majority of which have already gone extinct from the current vegetation of the study sites.

Investigation of ecological potentials of the Eger Model Region by GIS methods

Various parts of a landscape unit or region can be used for multiple purposes. Before the collectivisation of agricultural fields in the 1960s, the use of the land was more or less in accordance with the given natural conditions. Aft er collectivisation, huge plots were created, neglecting the features of the capability of the area. The map of ecological potential types shows favourable and unfavourable conditions for agricultural and forestry use, i.e. it indicates which parts of the region off er the best ecological conditions for arable cultivation, viticulture, fruit production, cultivation of meadows and pasture, just to mention a few. A capability assessment using GIS is being carried out for the total area of the Eger region. The database used for the capability analysis contains the Corine 1990 and 2006 data, soil maps and the National Gully Cadastre. The map is compared with present-day land use and the discrepancies between landscape capability and present land use are identified. Suggestions are made to optimise land use according to the capability map. Alterations since the change of the regime in 1989 have been determined and analysed from the aspect of suitability, as well.

Geomorphology of the Anthropocene: Time-transgressive discontinuities of human-induced alluviation

Alluvial sediments are an integral and environmentally sensitive component of the geological record and may be preserved both in subsiding basins and by uplift. This paper examines the Holocene alluvial record of a high-order fluvial discontinuity within the mid to late Holocene that is evident on all continents except Antarctica. The time-transgressive nature of this discontinuity, even over short distances, is revealed by two similar small-catchments in the UK which have a similar response to arable cultivation but separated in time by approximately 3000 years. It is argued that this anthropogenic discontinuity is likely to be an enduring signal as it exists well outside potentially future-glaciated areas and will be preserved in Holocene river terraces due to recent and future channel incision. This will make a marked lithological and sedimentological difference between this Middle-Late Holocene terrace and Pleistocene terraces which will also include a biological turnover with the appearance of new taxa, largely domesticates and synanthropes. Discussions of the Anthropocene as a geological period will have to accommodate this data and this may have important implications for the status and demarcation of the Anthropocene as a period in Earth System history.

Comparison of soil carbon stocks in Scottish soils between 1978 and 2009

SummaryThe change in soil carbon (C) stock over a 19–31‐year period (mean 25 years) has been measured at 179 sites on a 20‐km grid across Scotland. Sampling was by horizon from a profile pit. Although soil bulk density determinations were absent at the first sampling time, we used bulk density values from the second sampling time calibrated against NIR spectra to predict the missing values. There was no detectable change in overall total soil C stock (mean ± standard error, to a depth of 100 cm), which was 266 ± 15 and 270 ± 15 t C ha−1 for the first and second sampling times, respectively, or generally in C stock within specific vegetation or soil types. The exception was for soils under woodland, excluding those on deep peat, which exhibited a significant (P = 0.05) gain of 1.0 t C ha−1 year−1. Soils under woodland (mainly coniferous plantation) also showed a significant (P = 0.04) increase in C content (g kg−1), a significant decrease in bulk density (P = 0.006) and an increase in the thickness of the Litter‐Fermentation‐Humus (LFH) layer (P = 0.06). Recalculating the C stock to a depth of 15 cm showed a significant increase in overall C stock (when deep peat sites were excluded) as well as specifically in moorland and woodland soils, suggesting that had we sampled only to 15 cm, we would have reached a different conclusion. Both improved grassland soils and those initially under arable cultivation showed a significant decrease in C content. However, the mean thickness of Ap horizons increased from 29 to 32 cm, with a concomitant decrease in C content and a slight increase in bulk density; this we ascribe to deeper ploughing between the sample periods. In the context of possible soil C losses, we can be 95% confident that the mean loss does not exceed 0.2% year−1 and 99% confident that it does not exceed 0.4% year−1.

Abandonment and Expansion of Arable Land in Europe

Abandonment of arable land is often assumed to happen mostly in marginal areas where the conditions for arable cultivation are relatively unfavorable, whereas arable expansion is expected to occur mostly in areas with favorable conditions. This assumption, used in many land-use change forecasts, was never properly tested, mainly because the relatively short period of full-coverage land-use inventories did not allow a systematic analysis of the phenomena. With the recent release of CORINE 2006 this has changed. In this article, we explore the typical locations of abandonment and expansion of arable land in Europe during the period 1990–2006 by means of logistic regressions. More specifically, we test whether or not locations of abandonment and expansion can be inferred from the location characteristics of arable land in 1990. If the above assumption holds, this should be the case. We demonstrate that although arable expansion indeed happens in locations that resemble the bulk of arable land in 1990 (the presumably favorable locations), arable abandonment does not necessarily happen in locations that resemble the bulk of uncultivated land (that is, the presumably unfavorable locations). In other words, the assumption does not hold. Particularly, areas close to the road network were found to be associated with both high abandonment rates and high expansion rates, which suggest that abandonment is not limited to areas that are marginal in terms of agricultural production.

Assessment of soil quality using soil organic carbon and total nitrogen and microbial properties in tropical agroecosystems

Assessment of soil quality is an invaluable tool in determining the sustainability and environmental impact of agricultural ecosystems. The study was conducted to assess the quality of the soils under arable cultivation, locally irri-gated and non-irrigated, forestry plantations of teak (Tectona grandis Lin.) and gmelina (Gme- lina arborea Roxb.), and cashew (Anacardium occidentale Lin.) plantation agro ecosystems using soil organic carbon (SOC), soil total ni-trogen (STN) and soil microbial biomass C (SMBC) and N (SMBN) at Minna in the southern Guinea savanna of Nigeria. Soil samples were collected from soil depths of 0-5 cm and 5-10 cm in all the agro ecosystems and analyzed for physical, chemical and biological properties. All the agro ecosystems had similar loamy soil texture at both depths. The soils have high fer-tility status in terms of available phosphorus and exchangeable calcium, magnesium and po- tassium. The irrigated arable land had significantly (P 6.6 suggesting fungal domination in all the agroecosystems. The forestry plantation soils had higher SMBC and SMBN as a per-centage of SOC and STN respectively than the cultivated arable land soils. Burning for clearing vegetation and poor stocking of forestry planta-tions may impair the quality of the soil. The study suggests that the locally irrigated agro- ecosystem soil seems to be of better quality than the other agroecosystem soils.

A palynological and geoarchaeological investigation into Bronze Age farming at Belderg Beg, Co. Mayo, Ireland

This contribution describes the results and interpretations of geoarchaeological and palynological analyses of a soil profile near to a 14C dated Bronze Age roundhouse in a sub-peat field system at Belderg Beg, north Mayo in western Ireland, which displayed field-scale evidence of tillage in the form of cultivation ridges. This evidence of arable cultivation was supported by the presence of quernstones in the roundhouse, but there was no supporting evidence from other forms of socio-economic analysis. Soil micromorphological analysis was employed to define how the ridges were created and with what tools; pollen analysis was used to characterise the surface vegetation and test the purpose of the ridges. The results unequivocally showed that a phase of ard cultivation was followed after a brief hiatus by ridge-and-furrow tillage. There were tentative indications of possible amendment of the earlier, ard-worked soil, and more definitive evidence of midden material addition to the ridged soil. An AMS radiocarbon assay on the base of peat overlying the ridges indicated that tillage occurred in the Mid to Late Bronze Age.

Analysis of organic farming’s economic viability at different subsidy levels

Applying a data-collection-based economic model, I analyzed the economic viability of organic farming at different subsidy levels. The database is concentrated on the Hortobagy region. On the basis of data, I built an average sized and operated organic farm model with both arable land cultivation and animal keeping activities. The analysis of viability is based on gross profit calculation and compared with the criteria of the long-term economic viability, determined by the author. This study summarizes the most important results of the analysis.

An experimental study of crust development on chalk downland soils and their impact on runoff and erosion

SummaryThe sealing of soil surfaces by rainfall, the development of soil crusts and their impact on runoff and erosion was investigated in the laboratory by means of simulated rainfall. The soils investigated were stone‐free samples of chalk soils from southeast England, and soils with a 25% cover of stones. Vertical change to the surface and immediate subsurface of the soils was assessed through the examination of thin sections scanned into a computer and analysed with image processing software. Changes in roughness and microtopography of the soil surface were measured by use of a laser micromapper. Crusting occurred both in the presence and absence of stones and was inversely related to the organic matter content and aggregate stability of the soils. Crusting of stone‐free soils was accompanied by a reduction in roughness of the soil surface, but roughness of the stone‐covered surfaces increased as crusting developed. Increases in the particle density of the crust were related to silt content. Organic‐rich soil from under permanent grass and from a soil recently brought into arable cultivation crusted less than soils used for arable cultivation for longer periods with lower organic content. The inwashing of silt into the pores of the soil during crusting reduces infiltration, and increases runoff and erosion. In the presence of a 25% cover of surface stones, the reduction in infiltration was 25% less than for stone‐free soils and erosion ∼50% less.

Estimation of rainfall indices for the determination of length of growing season and timing of arable crop cultivation in Ogun State

The study assessed the rainfall distribution pattern over the last 25 years (1989-2004) to determine the length of growing season and timing of arable crop cultivation in Ogun State. Secondary rainfall data was obtained from the four meteorological stations in the State and subjected to arithmetic calculations for estimation of raindays, drydays and rainfall variability in the study areas. The results show that the month of March marks the onset of rainy season in the State while October marks its cessation. Out of the growing period of 208 days, 88 days were observed as having sufficient rainfall (0.25mm and above) per day. Based on Seasonality Index (S.I) of 0.32 and monthly and annual coefficient of variability of less than 50 percent and 20 percent, respectively, estimated for the study area, it was ascertained that the raindays were well spread out through the months of the rainy season. Observed high frequencies of 2 and 4 dryday spells suggest that rainfall will take place mostly after 2 or 4 successive days of no rain. In the light of this, it was concluded that rainfall situation in Ogun State will favourably support arable crop cultivation and as such land preparation should be completed by mid-April and followed by seed sowing between then and early May. Keywords : Rainday; dryday spell; rainfall variability length of growing season, and timing of arable crop cultivation Moor Journal of Agricultural Research Vol. 7 (1&2) 2006 pp. 56-62