No abstract

Conservation tillage is expected to have a positive effect on soil physical properties, soil Carbon (C) storage, while reducing fuel, labour and machinery costs. However, reduced tillage could increase soil nitrous oxide (N2O) emissions and offset the expected gains from increased C sequestration. To date, conservation tillage is barely practiced or studied in Bosnia and Herzegovina (BH). Here, we report a field study on the short-term effects of reduced (RT) and no tillage (NT) on N2O emission dynamics, yield-scaled N2O emissions, soil structure and the economics of cereal production, as compared with conventional tillage (CT). The field experiment was conducted in the Sarajevo region on a clayey loam under typical climatic conditions for humid, continental BH. N2O emissions were monitored in a Maize-Barley rotation over two cropping seasons. Soil structure was studied at the end of the second season. In the much wetter 2014, N2O emission were in the order of CT > RT > NT, while in the drier 2015, the order was RT > CT > NT. The emission factors were within or slightly above the uncertainty range of the IPCC Tier 1 factor, if taking account for the N input from the cover crop (alfalfa) preceding the first experimental year. Saturated soils in spring, formation of soil crusts and occasional droughts adversely affected yields, particularly in the second year (barley). In 2014, yield-scaled N2O emissions ranged from 83.2 to 161.7 g N Mg-1 grain (corn) but were much greater in the second year due to crop failure (barley). RT had the smallest yield-scaled N2O emission in both years. NT resulted in economically inacceptable returns, due to the increased costs of weed control and low yields in both years. The reduced number of operations in RT reduced production costs and generated positive net returns. Therefore, RT could potentially provide agronomic and environmental benefits in crop production in BH.

The present study addresses the short-term effects of different harvest intensities under close-to-nature selective management on the upper soil layers in Slovenian and Bosnian Dinaric karst fir-beech forests. The different harvest intensities coincided with the single-tree and irregular shelterwood management, common in the region. The effect of harvesting intensity on the upper soil layers (Ol, Of, Ol and 0–10 cm mineral soil) was investigated by a repeated measurements experiment in Slovenia on 27 research plots in close-to nature managed forests. The properties of the upper layers (concentration of SOC and TN, C/N ratio, weights, BD and SOC stocks) were analyzed twice, before (2011) and after (2014) treatment of 50% and 100% harvest intensity in relation to the total standing growing stock of trees. As a control, we used no-treatment <20% harvesting intensity plots. To extend this experiment, we added three comparable plots from the Bosnian site: one in an old-growth forest with 0% harvest intensity and two in the managed forest with <20% harvest intensity. The results of the assessment of mean differences indicated a significant influence of harvesting intensity on the decrease in SOC, TN concentrations, weights and SOC stocks in the organic layers and the increase in BD and SOC stocks in the 0–10 cm mineral soil. The highest relative decreases in Ol, Of and Oh SOC stocks occurred in 50% (−10 and −38%) and 100% (−16 and −49%) harvest intensities. Negligible relative differences in both organic and 0–10 cm mineral layers were found for the <20% harvest intensity in the region. The change in forest light conditions resulting from differences in canopy openness as a function of applied harvest intensity explained the significant difference in the properties of the upper soil layers. The impact of the short-term losses in SOC stocks, in terms of overall soil productivity, may depend on the regeneration dynamics and melioration methods.

No abstract

In Bosnia and Herzegovina (BiH) there are no available data on permanent losses of agricultural land and it is evident that all the research and professional and scientific literature still uses the information of annual land loss in the amount of 3,000 ha which, according to the available references, has been in use since 1977 (Resulović, 1977-2010). The subject of this scientific research is to investigate changes in the use of agricultural land in BiH, sectoral policies and factors affecting these changes as well as the quality of official data on land and land use change. Analyzed as part of this research were three sets of data: statistical data (1961-1991), cadastral records (1973-1991) and CORINE data on land cover changes (2000-2018). Researches have shown that trends in changes in total agricultural land by all categories of use were not linear and were considerably affected by the socioeconomic development and sectoral policies. This study has shown that total agricultural land, according to statistical records from 1961-1991, was reduced by 101,222 ha (3,374 ha/yr). Within the category of arable land, the biggest permanent losses were recorded in cropland and gardens, amounting to 207,823 ha or 6,927 ha/yr, while in some other categories within the arable land an increase was recorded. According to cadastral records for the period 1973-1991, the total decrease of agricultural land amounts to 58,186 ha (3,232 ha/yr). According to CORINE data, the reduction of agricultural land in the period 2000-2018 is 14,152 ha or 786 ha/yr.