The age of vines as a controlling factor of soil erosion processes in Mediterranean vineyards

Vineyards incur the highest soil and water losses among all Mediterranean agricultural fields. The state-of-the-art shows that soil erosion in vineyards has been primarily surveyed with topographical methods, soil erosion plots and rainfall simulations, but these techniques do not typically assess temporal changes in soil erosion. When vines are planted they are about 30 cm high × 1 cm diameter without leaves, the root system varies from 2 to over 40 cmdepth, and sometimes the lack of care used during transplanting can result in a field with highly erodible bare soils. This means that the time since vine plantation plays a key role in soil erosion rates, but very little attention has been paid to this by the scientific community. Thus, the main goal of this research was to estimate soil losses and assess soil erosion processes in two paired vineyard plantations of different ages. To achieve this goal, the improved stock unearthing method (ISUM) was applied to vineyards on colluvial parent materials with similar soil properties, topographical characteristics and landmanagements in the Les Alcusses Valley, southwestern Valencia province, Spain. Our findings suggested that the old vineyards showed lower erosion rates (−1.61 Mg ha−1 yr−1) than those that were recently planted (−8.16 Mg ha−1 yr−1). This is because of the damage that the plantation of the vines causes to soil. Tillage after planting (4 times per year) resulted in changes in the inter-rowand rowmorphology, promoting the development of a ridge underneath the vines that disconnected the inter-rows and reduced soil losseswith time. After the second year and until the 25th year after plantation, soil erosionwas approximately 1Mg ha−1 y−1,whichmeans thatmost of the erosion took place during the first two years after the plantation. Soil conservation strategies should be applied immediately after the plantationworks to allow sustainable grape production. That is when soil erosion most needs to be controlled

Geodiversity and geoheritage: Detecting scientific and geographic biases and gaps through a bibliometric study

Many scientists have recognized that there is diversity in nature, including biodiversity, geodiversity, and pedodiversity. Studies in biodiversity date back as far as the 1700s, but geodiversity and pedodiversity studies are much more recent, dating to the late 1970s to early 1980s. Given that we are now approaching 40 years of geodiversity and geoheritage work, this study was undertaken to determine areas that have been well addressed and where current gaps are. This was accomplished by reviewing the publications in the journal 'Geoheritage', the Scopus and Google Scholar databases, and established geoparks according to UNESCO records. It was found that geodiversity studies typically do not include the findings or utilize the techniques of biodiversity and pedodiversity research, despite the fact that common definitions of geodiversity include soils. Including the findings and techniques of bio- and pedodiversity would expand geodiversitywork. Likewise, geoheritage preservation sites are not geographically balanced, with European countries, Brazil, Australia, and China creating the large majority. The European and East Asian countries, especially China, have dominated in the establishment of geoparks. The most pressing need in future studies is more balanced geographic distribution, as the current strong slant towards a limited portion of the world cannot adequately capture (on the research front) and preserve (on the geoparks front) global geodiversity. Finally, there is a need investigate whether the spatial patterns of biodiversity are idiosyncratic or are also a characteristic of abiotic resources, permitting the standardization of diversity research methods. This review contends that there are intriguing similarities in biodiversity, geodiversity, and pedodiversity patterns that should be explored, something that would benefit all of these research areas

The impact of agricultural management on selected soil properties in citrus orchards in Eastern Spain: A comparison between conventional and organic citrus orchards with drip and flood irrigation. , 581, 153-160.

The agricultural management of citrus orchards is changing from flood irrigated managed orchards to drip irrigated organic managed orchards. Eastern Spain is the oldest and largest European producer of citrus, and is representative of the environmental changes triggered by innovations in orchard management. In order to determine the impact of land management on different soil quality parameters, twelve citrus orchards sites were selectedwith different land and irrigation management techniques. Soil samples were taken at two depths, 0-2 cmand 5-10 cm for studying soil quality parameters under the different treatments. Half of the studied orchardswere organicallymanaged and the other sixwere conventionally managed, and for each of these six study sites three fields were flood irrigated plots and the other three drip irrigated systems. The outcome of the studied parameters was that soil organic matter (SOM) and aggregate stability were higher for organic farms. Bulk density and pH were only significantly different for organic farms when drip irrigation was applied in comparison with flooded plots. C/N ratio did not vary significantly for the four treatments. Although there are some points of discussion, this research shows that a combination of different management decisions leads to improvement of a couple of soil quality parameters. Organic management practiceswere found to be beneficial for soil quality, compared to conventional management for soils with comparable textures and applied irrigation water

Performance assessment of individual and ensemble data-mining techniques for gully erosion modeling

Gully erosion is identified as an important sediment source in a range of environments and plays a conclusive role in redistribution of eroded soils on a slope. Hence, addressing spatial occurrence pattern of this phenomenon is very important. Different ensemble models and their single counterparts, mostly data mining methods, have been used for gully erosion susceptibility mapping; however, their calibration and validation procedures need to be thoroughly addressed. The current study presents a series of individual and ensemble dataminingmethods including artificial neural network (ANN), support vector machine (SVM), maximum entropy (ME), ANN-SVM, ANN-ME, and SVM-ME to map gully erosion susceptibility in Aghemam watershed, Iran. To this aim, a gully inventory map along with sixteen gully conditioning factors was used. A 70:30% randomly partitioned sets were used to assess goodness-of-fit and prediction power of the models. The robustness, as the stability ofmodels' performance in response to changes in the dataset, was assessed through three training/test replicates. As a result, conducted preliminary statistical tests showed that ANN has the highest concordance and spatial differentiation with a chi-square value of 36,656 at 95% confidence level,while theME appeared to have the lowest concordance (1772). The ME model showed an impractical result where 45% of the study area was introduced as highly susceptible to gullying, in contrast, ANN-SVMindicated a practical resultwith focusing only on 34% of the study area. Through all three replicates, the ANN-SVM ensemble showed the highest goodness-of-fit and predictive power with a respective values of 0.897 (area under the success rate curve) and 0.879 (area under the prediction rate curve), on average, and correspondingly the highest robustness. This attests the important role of ensemble modeling in congruently building accurate and generalized models which emphasizes the necessity to examine different models integrations. The result of this study can prepare an outline for further biophysical designs on gullies scattered in the study area

Assessment of soil particle erodibility and sediment trapping using check dams in small semi-arid catchments

Check dams can be used as a source of information for studies on sediment characteristics and soil particle erodibility. In this study, sediment yield and grain size distribution (GSD) were measured in twenty small catchments draining into a rock check dam in NW Iran for different runoffs during 2010-2011. Significant correlations were found between sediment yield and slope steepness, vegetation cover and soil erodibility factor (K) of the catchments. The erodibility of soil particles was determined using the comparison of GSD between sediment and original soil. Clay was the most erodible soil particle which showed 2.05 times more percentage in sediment than the original soil. The erodibility of soil particles were strongly affected by the rainfall erosivity (EI30). Check dams showed more effectiveness in trapping coarse particles (sand and gravel). The effectiveness of check dams in trapping coarse particles enhanced with increase in the remaining capacity of check dams

Characterizing rainfall erosivity by kinetic power-Median volume diameter relationship

Kinetic power, i.e. kinetic energy per unit time and area, is the variable widely used to represent the rainfall erosivity which affects soil loss and sediment yield. This paper shows the results of an experimental investigation using the raindrop size distributions (DSDs) measured by an optical disdrometer installed at the Department of Agricultural, Food and Forestry Sciences of University of Palermo in Italy (June 2006-March 2014) and at the El Teularet experimental station in Spain (July 2015-May 2016). At first an analysis of the DSDs aggregated into intensity classes is carried out, then the measured kinetic power values are determined. The aggregated DSDs allowed to establish that the median volume diameter of the distribution is affected by raindrops characterized by the greatest values of the diameters that composes precipitation. The measured kinetic power values allowed to verify the reliability of kinetic power-rainfall intensity relationships proposed by Wischmeier and Smith and Kinnell. Finally, using all the available measurements of kinetic power, rainfall intensity and median volume diameter obtained in different climatic contexts and by different measurement techniques, this paper demonstrates that the ratio between kinetic power and rainfall intensity depends strictly only on median volume diameter of the distribution according to a single site-independent relationship. Therefore the estimate of the kinetic energy per unit volume of rainfall does not require the knowledge of the whole drop size distribution. The reliability of a theoretical relationship relating the kinetic power per unit volume of rainfall to median volume diameter is also positively verified using all available measurements

The Contrasted Impact of Land Abandonment on Soil Erosion in Mediterranean Agriculture Fields

Abandonment of agricultural land results in on- and off-site consequences on soil system and there is a need to evaluate the impact on soil erosion to understand the ecosystem's changes. The aim of this research is to assess the impact of abandonment in four Mediterranean crops (vineyards, almonds, citrus and olives) on soil and water losses. To achieve this goal, 105 rainfall simulation experiments were conducted in agriculture fields (vineyards in Málaga, almonds in Murcia, and citrus and olive in Valencia) and on the paired abandoned plots. After abandonment, soil detachment decreased drastically in the olive and citrus orchards, meanwhile vineyards did not show any difference and almonds registered higher erosion rates after the abandonment. Terraced orchards of citrus and olives recovered a dense vegetation cover after the abandonment, meanwhile the sloping terrain of almonds and vineyards enhanced the development of crusts and rills and a negligible plant cover that resulted in high erosion rates. The contrasted response of the abandonment is discussed

An economic, perception and biophysical approach to the use of oat straw as mulch in Mediterranean rainfed agriculture land

Soil erosion is a key cause of land degradation in agriculture lands; and it is a worldwide threat that must be solved by means of nature-based strategies to be able to achieve sustainability. The use of mulches can be a solution, but there is a lack of information on long-term effects of the use of straw. Furthermore, little is known about the perception of farmers and the economic cost on the implantation of straw as a conservation measure. Eight paired plots were selected in Sierra de Enguera on an agriculture field to determine the effect of straw cover on soil erosion. Four plots were tilled three times per year (Control) and four plots were not ploughed and 0.125 kg m−2 y−1 of oat straw cover was applied yearly (Straw). The plots were established in 2002, and runoff and sediment was continuously collected after each rainfall event from 2004 till 2014 when the two managements were applied. The results show an immediate effect of the straw mulches as in these plots the runoff (from 7.7 till 5.9%) and soil erosion (from 47 till 26 Mg ha−1 y−1) was reduced already in the first year. The combined effect of the use of straw yearly and the no-tillage strategy resulted in a reduction of the sediment yield, and 11 years later soil erosion rates were two orders of magnitude lower than in the control plot. However, the perception of the farmers on the use of straw is very negative and they claim that subsidies need to be implemented, as the cost of straw mulch is 1.9 times more expensive than traditional tillage

Assessing land condition as a first step to achieving land degradation neutrality: A case study of the Republic of Srpska

Land Degradation Neutrality (LDN) is a key voluntary and aspirational target of Sustainable Development Goal (SDG) 15 which urges countries to protect, restore and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss. A first and critical important step in the implementation of LDN is assessing the current land condition using not only active restoration of degraded land, but also targeting land degradation drivers behind the land degradation process. In a first step to achieve these goals, countries were provided a global dataset for three sub-indicators of land degradation: land cover (LC), land productivity dynamics (LPD) and soil organic carbon (SOC). Here, we report on trends in these sub-indicators for the Entity Republic of Srpska (RS) as a part of Bosnia and Herzegovina, which is a key analysis to inform the frame of reference or baseline conditions for the region to evaluate LDN across this region. Global data for LC for the RS indicates a 0.5% loss of forests (6400 ha) over the time period from 2000 to 2010. Of this area, 5000 ha were converted to cropland and an additional 1400 ha was converted to shrubs, grasslands and sparsely vegetated areas. LPD declined over 2.5% (63,500 ha) of the region. SOC declined on land use changed areas by 15.6% (74,609 Mg ha−1) over the same time period. Based on global data, we estimated that 3% of the country is in a degraded state. Based on interviews with local stakeholders in 31 local communities, the primary land degradation drivers were identified and validated by team experts. Depopulation and migration to urban centers were identified as the important underlying drivers of land degradation that most municipalities are facing. The most frequent direct drivers of land degradation across this region were land abandonment, floods, drought, erosion and urbanization. Land abandonment, more specifically, has resulted in conversion of agriculturally productive lands to lands dominated by a wide range of invasive species over the last 25 years. Continued land degradation is underpinned by the lack of understanding by stakeholders of the importance of land as a resource. In evaluating the status, trends and drivers of land degradation for this region, we have identified key areas or 'hot spots' that may be targeted for restoration options and may be used to achieve LDN targets by 2030

Effects of parent material on soil erosion within Mediterranean new vineyard plantations

Parent material can determine specific physical and chemical soil properties and, therefore, soil erosion rates. However, for new vine plantations, there is not enough research on soil erosion assessment on different parent materials which could be helpful for agricultural management plans. The main aim of this research was to quantify soil erosion rates of two recent vineyard plantations under similar climate and land use management conditions, but on different parent materials, namely colluvium (2 years old) and marls (8 years old), located within the Les Alcusses valley vineyards in Eastern Spain. To achieve this goal, the ISUM (improved stock unearthing method) was applied. ISUM involves measurements of vertical distances from a horizontally stretched meter band attached to opposite pair vine plants to the topsoil surface at 5 sampling points along the cross sections of the pair vine rows. The original surface level was determined from the fixed distance of 2 cm of the graft unions from the soil surface. Digital elevation modelling of the vertical measurements was used to infer the erosion rates. Annual total soil erosion rates were 87.7 Mg ha−1 year−1 and 4.35 Mg ha−1 year−1 in the marls and colluvium plots, respectively. For the marls plot, 67% of the depletion occurred in the inter-row areas, whereas for the colluvium plot the inter-row areas registered 4.78 Mg ha−1 year−1 depletion and the row areas showed only a deposition of 0.44 Mg ha−1 year−1. We hypothesised that the inter-row areas registered the highest erosion rates due to the tillage practices. In the row areas, the cover of the vines possibly reduced soil erosion rates and acted as sinks for sediments. This behaviour of the inter-row areas acting as sources and the row areas as sinks for sediments was more evident on the colluvium plot, while most sections on the marls plot showed intense erosion features. It is suggested that more attention should be paid by policymakers and stakeholders to these differences when new plantations are introduced on marls and colluvium vineyards. We claim that initial soil erosion control measures should be applied during the first few years of plantations instead of when the vineyards are much older and soil has already been mobilised