Crop residues in corn-wheat rotation in a semi-arid region increase CO2 efflux under conventional tillage but not under no-tillage system

Appropriate management of crop residue plays a key role in mitigating greenhouse gas emissions. However, it has been inadequately implemented in general agricultural management practices. In a field investigation using static chambers, we evaluated the effects of crop residue at three different rates - 100 % (R100), 50 % (R50), and residue removal (R0) - on carbon dioxide (CO2) efflux. The field study was conducted in corn-wheat rotation under conventional (CT) and no-tillage (NT) systems in a semi-arid region. The main results showed that CO2 efflux was positively correlated with higher soil temperature (0.43–0.79) and microbial biomass carbon (0.66–0.89). The crop residue treatments affected these traits. A strong positive relationship between CO2 efflux and the crop residue (R2 = 0.96, CT and R2 = 0.9 for NT) was observed. In the CT system, significant increases were detected among residue rates on cumulative CO2 efflux, where R100 and R50 resulted in 36 % and 25 % higher cumulative CO2 efflux, respectively, than R0. In contrast, there was no significant difference in cumulative CO2 efflux among the crop residue retention (R100 and R50) and removal (R0) treatments under the NT system. Our study revealed that crop residue retention led to increased CO2 efflux under the CT system in semi-arid conditions during the first year of application, while under the NT system, CO2 efflux was not impacted by crop residue. Our results indicate that there is considerable potential for improving soil management practices in the context of soil degradation, climate change, increasing crop productivity, and carbon (C) sequestration

Land Use Changes and Their Perception in the Hinterland of Barranquilla, Colombian Caribbean

The coastal strip of the western peri-urban area of Barranquilla in the Atlántico Department (Colombia) is experiencing changes in human-environment interactions through infrastructure, residential, and tourism projects in a vulnerable landscape. In the hilly area, fragments of biodiverse tropical dry forest still exist in various states of conservation and degradation. To understand the interrelated social, economic, and ecological transformations in the area, we analyzed land use change on the local scale including the local community’s perception, because the local community is a key actor for sustainable land use. For the analysis of the interrelated social, economic, and ecological processes, we combined visual interpretation of high-resolution satellite imagery, on-site field land use mapping, and a spatial statistical analysis of the distribution of land use classes with in-depth interviews and a participatory GIS workshop, thus benefitting from the complementary methodological strengths of these approaches. The case study is the rural community of El Morro, which exhibits the typical social, economic, and ecological changes of the coastal strip of the western peri-urban area of Barranquilla. The local community perceives a continuous loss of forest area, but observations from on-site field mapping cannot confirm this linear trend. We observed a gradual replacement of traditional land uses such as smallholder agriculture, charcoal production, and cattle breeding by services for tourism, gated community projects for urban dwellers, and infrastructure projects; these spatial developments have several characteristics of rural gentrification. We conclude that the drivers of environmental degradation have changed and the degradation increased. The development projects of external companies have been rejected by the local community and have induced environmental consciousness among community members. Thus, the local community has become an advocate for sustainable land use in the study area

Environmental impacts of corn silage production: influence of wheat residues under contrasting tillage management types

Acknowledgements The authors gratefully acknowledge the financial support provided by Iran National Science Foundation (INSF). Funding for open access charge: Universidad de Granada / CBUA.Funding Funding for open access charge: Universidad de Granada / CBUA. This study received financial support provided by the Iran National Science Foundation (INSF).Data Availability The data that support the findings of this study are available from the corresponding author, (A. C. C.), upon reasonable request.The intensification of specific land management operations (tillage, herbicide, etc.) is increasing land degradation and contributing to ecosystem pollution. Mulches can be a sustainable tool to counter these processes. This is particularly relevant for rural areas in low-income countries where agriculture is a vital sector. In this research, the environmental impact of different rates of wheat residues (no residues, 25, 50, 75, and 100%) in corn silage cultivation was evaluated using the life cycle assessment (LCA) method under conventional tillage (CT) and no-tillage (NT) systems in a semi-arid region in Karaj, Iran. Results showed that in both tillage systems, marine aquatic ecotoxicity (ME) and global warming potential (GWP) had the highest levels of pollution among the environmental impact indicators. In CT systems, the minimum (17,730.70 kg 1,4-dichlorobenzene (DB) eq.) and maximum (33,683.97 kg 1,4-DB eq.) amounts of ME were related to 0 and 100% wheat residue rates, respectively. Also, in the CT system, 0 and 100% wheat residue rates resulted in minimum (176.72 kg CO2 eq.) and maximum (324.95 kg CO2 eq.) amounts of GWP, respectively. However, in the NT system, the 100% wheat residue rate showed the minimum amounts of ME (11,442.39 kg 1,4-DB eq.) and GWP (120.21 kg CO2 eq.). Also, in the NT system, maximum amounts of ME (17,174 kg 1,4-DB eq.) and GWP (175.60 kg CO2 eq.) were observed with a zero wheat residue rate. On-farm emissions and nitrogen fertilizers were the two factors with the highest contribution to the degradation related to environmental parameters at all rates of wheat residues. Moreover, in the CT system, the number of environmental pollutants increased with the addition of a higher wheat residue rate, while in the NT system, increasing residue rates decreased the amount of environmental pollutants. In conclusion, this LCA demonstrates that the NT system with the full retention of wheat residues (100%) is a more environmentally sustainable practice for corn silage production. Therefore, it may be considered one of the most adequate management strategies in this region and similar semi-arid conditions. Further long-term research and considering more environmental impact categories are required to assess the real potential of crop residues and tillage management for sustainable corn silage production.Funding for open access charge: Universidad de Granada/CBUAIran National Science Foundation (INSF

Soil Nitrous Oxide Emissions Following Crop Residues Management in Corn-Wheat Rotation Under Conventional and No-Tillage Systems

Agricultural activity is the major anthropogenic source of nitrous oxide (N2O) emissions from terrestrial ecosystems. Conservation agriculture including crop residue management can play a key role in enhancing soil resilience to climate change and mitigating N2O emissions. We investigated the effects of crop residue rates, including 100 % (R100), 50 % (R50), and residue removal (R0), on N2O emissions in corn-wheat rotation under conventional (CT) and no-tillage (NT) systems. The key factors evaluated affecting N2O emissions included soil temperature, soil moisture, soil ammonium, and soil nitrate concentrations. Results showed that the N2O emissions increased with the increasing rate of residue under both CT and NT systems. Both R100 and R50 significantly (p < .05) increased the N2O emissions compared to R0 during the annual rotation cycle. Soil moisture and mineral nitrogen (ammonium and nitrate) were the main driving factors that stimulated N2O emission in both CT and NT systems. In the NT and CT systems, cumulative N2O emissions showed a significant increase with R50 (+75.5 % in NT, +36.5 % in CT) and R100 (+134 % in NT, +40 % in CT) as compared to R0. Furthermore, no significant differences were found between R100 and R50 in the CT system, while in the NT system significant increases were observed for R100 compared to R50. Overall, our study justified as a first approach only during the first year that crop residue removal led to decreased N2O emissions under semi-arid conditions. However, due to the deteriorating impact of crop residue removal on crop productivity and soil C sequestration, this management method cannot be considered a sustainable agronomic practice. We suggest long-term studies to determine the appropriate rate of postharvest crop residue to achieve less N2O emissions and climate-friendly agricultural practices.Iran National Science Foundation (INSF)National Research, Development & Innovation Office (NRDIO) - Hungary TNN 12345

Crop residues in corn-wheat rotation in a semi-arid region increase CO2 efflux under conventional tillage but not in a no-tillage system

Appropriate management of crop residue plays a key role in mitigating greenhouse gas emissions. However, it has been inadequately implemented in general agricultural management practices. In a field investigation using static chambers, we evaluated the effects of crop residue at three different rates - 100 % (R100), 50 % (R50), and residue removal (R0) - on carbon dioxide (CO2) efflux. The field study was conducted in corn-wheat rotation under conventional (CT) and no-tillage (NT) systems in a semi-arid region. The main results showed that CO2 efflux was positively correlated with higher soil temperature (0.43–0.79) and microbial biomass carbon (0.66–0.89). The crop residue treatments affected these traits. A strong positive relationship between CO2 efflux and the crop residue (R2 = 0.96, CT and R2 = 0.9 for NT) was observed. In the CT system, significant increases were detected among residue rates on cumulative CO2 efflux, where R100 and R50 resulted in 36 % and 25 % higher cumulative CO2 efflux, respectively, than R0. In contrast, there was no significant difference in cumulative CO2 efflux among the crop residue retention (R100 and R50) and removal (R0) treatments under the NT system. Our study revealed that crop residue retention led to increased CO2 efflux under the CT system in semi-arid conditions during the first year of application, while under the NT system, CO2 efflux was not impacted by crop residue. Our results indicate that there is considerable potential for improving soil management practices in the context of soil degradation, climate change, increasing crop productivity, and carbon (C) sequestration.Universidad de Granada/CBUAIran National Science Foundation (INSF

Influence of Logos on Social Attitudes toward the Landscape of Protected Areas: The Case of National and Natural Parks in Spain

This study is the first analysis of the influence of the design of the logos of the National and Natural Parks of Spain on social attitudes toward these protected areas (PAs). The effect of certain elements in the logo of a PA on its attractiveness and on support for its conservation was explored through a questionnaire survey of groups of university students. The respondents were asked to choose between different park logos, using three main criteria: tourist interest, conservation priority, and willingness to pay for conservation. The results showed a higher preference for PAs whose logos include animals and a lower preference for those with heritage elements. No significant differences were found in terms of types of university programs. The results suggest that greater attention should be paid to the role of iconographic elements in considerations of the protection and management of landscapes. This study adds to our understanding of the social mechanisms that influence the interest of the public in Natural and National Parks. These results can be used to increase the involvement of the general population in conservation goals, contributing to the social, economic, and environmental sustainability of PAs

Replacing chemical fertilizers with organic and biological ones in transition to organic farming systems in saffron (Crocus sativus) cultivation

To evaluate the response of saffron to animal manure, and biological and chemical fertilizer in an arid climate, an experiment was performed as split plots based on a randomized complete blocks design with three replications during three consecutive crop growth seasons (2015-2018) at the Research Farm of University of Gonabad, Iran. The experimental treatments included application (60 t ha(-1)) and non-application (control) of manure as the main plot and the use of biosulfur (5 kg ha(-1)), biophosphate (3 L ha(-1)), nitroxin (3 L ha(-1)), chemical fertilizer (150, 100, and 100 kg ha(-1) of urea, triple superphosphate, and potassium sulfate, respectively), and no fertilizer application (control) as the sub-plot. The results showed a highly significant response of the quantitative traits of saffron to the application of manure, which increased the leaf, flower, and corm indices of saffron by a mean of 15.1-35.7% than control. The interaction effect of manure with biological and chemical fertilizers for leaf, flower, and weeds indices of saffron was significant. There was no significant difference between the interaction treatments of manure and chemical fertilizer with nitroxin and biophosphorus fertilizers in most of the mentioned traits in the three experiment years. The simultaneous application of these fertilizers increased the average by about 60, 105, 135, 110, 165, and 55% of the leaf dry weight, the number of flowers, fresh flower yield, dry flower yield, dry stigma yield, and weed dry weight of saffron, respectively as compared to control. There was no significant difference between the chemical fertilizer with nitroxin or biophosphate in terms of the effect on the traits related to saffron corm so the use of these fertilizers, as compared to control, increased replacement corm weight, replacement corm size, and bud number per corm by, respectively, about 35, 60, and 40% on average. The chemical and biological fertilizers improved the content of crocin, picrocrocin, and safranal of saffron stigma. The best results were obtained from the use of chemical fertilizers, although no significant difference was observed between this treatment and the nitroxin and biophosphate treatments. Overall, the results of this three-year experiment show a very high response of the saffron plant to the simultaneous use of manure and biological fertilizers and, therefore, it is possible to replace chemical fertilizers with organic and biological fertilizers in saffron cultivation to implement organic agriculture and achieve acceptable quantitative and qualitative yields in areas similar to the experiment location.University of Gona-badUniversidad de Granada/CBU

Estimation of soil mobilization rates by a rainy period and intense tillage practices in vineyards—A case study in the Maule region (Chile)

Winemaking in Chile is a long tradition that is recognized around the world. It is especially important in the Maule region where more than 40% of the total wine in the country is produced. However, there is a lack of studies related to soil erosion in vineyards in Chile, especially considering the extreme rainfall events that occur in the country. This research estimates soil erosion mobilization rates before and after a rainy season between April 2020 and May 2020 using the "improved stock unearthing method" on two inter-row plots in a vineyard located in the Maule region of Chile. This method relies on the graft union as a bioindicator for assessing soil surface-level changes. Maps of the soil surface were obtained to show how soil depletion and accumulation points within the inter-row areas could be detected. It has been estimated that a total soil mobilization of 85.7 and 130 Mg ha yr(-1) had occurred in the inter-row areas 1 and 2, respectively, since the establishment of the plantation. However, a single rain event mobilized soil at rates of 5.5 and 3.5 Mg ha yr(-1), respectively, in the inter-row areas 1 and 2. We have demonstrated that erosive processes present in the study area exceed the rates of soil formation and the tolerable rates of erosion on a global scale. The results allow re-thinking of agricultural practices and management of soil systems to improve the sustainability of conventional Chilean vineyards and their soils.Universidad de Granada/CBUAComunidad de MadridBBVA Foundatio

Physicochemical and mineral properties of suspended sediments of the Tigris and Euphrates rivers in the Mesopotamian Plain

Most of the suspended river load from the Tigris and Euphrates rivers is deposited in the Mesopotamian Plain in Iraq. This suspended river load comprises sediments consisting of minerals and organic particles generated from weathering, erosion, transport, and sedimentation. Therefore, it is crucial to analyze, either quantitative or qualitatively, the types of minerals in the sediment particles transported by the suspended river load, in addition to the potential value they may add to the agricultural lands irrigated by the Tigris and Euphrates rivers. Herein, samples of suspended sediments were collected from both rivers for physical, chemical, and mineral assessments. The results revealed the predominance of silt particles, followed by clay, and then sand. The presence of clay particles increased while that of silt and sand decreased with further travel into the rivers. The pH values ranged from 7.39 to 7.70 and the electrical conductivity ranged from 1.39 to 2.16 ds m����� 1. The values of the total and active calcium carbonate minerals were 352.87–336.12 and 172.64–194.56 g kg����� 1 for the Tigris and Euphrates rivers, respectively. The mineral analysis identified the presence of non-clay minerals at a rate of 83 %, including calcite, quartz, albite, dolomite, and gypsum. Clay minerals, including chlorite, illite, montmorillonite, palygorskite, vermiculite, and kaolinite, were found at a rate of 17 %. Both rivers exhibited distributions of clay and non-clay minerals that vary as they move along the rivers