The Slope Association Type as a Comparative Index for the Evaluation of Environmental Risks

The topography is one of the determining site characteristics, of which the slope inclination is significant for natural science aspects, including the estimation of water erosion risk and as a criterion for agricultural subsidies. The slopes within an area vary greatly and occupy very different proportions of the area. Algorithms that take this heterogeneity into account were developed in the 1970s with the medium-scale agricultural site mapping (MMK). It also contains the slope association types (SAT, in German: “Hangneigungsflächentyp”), which classifies different slopes and summarizes them as one value per reference area. The SAT can be used across various scales and different targets. Applicability is given to soil and water conservation tasks, administrative tasks as field selection or agricultural subsidies, and over a wide range of scales from small catchments areas to whole landscape analyses. Thus, one value on an area basis characterizes an important topographic factor.

Arbuscular Mycorrhizal Fungi : Diversity and Its Impact with Abiotic Factors in Phoenix dactylifera L. of Kachchh Region, Gujarat, India

Mycorrhizal diversity of non-agricultural sites from Madhapar, Reladi and Anjar region of Kachchh regions were studied. Date palm is an economically important plant in dry lands of the world approach towards an investigation of AM fungi diversity and their association with the date palm in Kachchh. This is important to understand the root colonization, spore analysis and spore density in the study. The study is about the composition of AM fungi at an agricultural site. Also to understand the relevance of species composition and their relationship with abiotic factors. In the present work soil of agricultural field has been taken into consideration to understand the relevance.

Wet Deposition Fluxes of Nitrate and Ammonium at a Rural Agricultural Site in north India

<p>The chemical composition of rainwater is an indicator of the air quality and sources of influence. In this study, pH and ionic concentrations were measured in rain samples collected during monsoon season of 2018 at a rural agricultural site located in northern part of India. Wet deposition fluxes of reactive nitrogen species NH<sub>4</sub><sup>+</sup> over NO<sub>3</sub><sup>-</sup> were calculated to estimate their annual deposition. The pH of samples varied between 5.2 and 6.14, with an average value of 5.72 which is in alkaline range considering 5.6 as the neutral pH of cloud water with atmospheric CO<sub>2</sub> equilibrium. These relatively high pH values indicate the neutralisation of acidity in precipitation. Samples were analysed for their cationic and anionic content using ion chromatography. The results showed that NH<sub>4</sub><sup>+</sup> concentrations were higher than NO<sub>3</sub><sup>- </sup>with the VWM concentrations of 187.23 μeql<sup>-1</sup> and 26.79 μeql<sup>-1</sup> respectively. Furthermore, wet deposition flux of NH<sub>4</sub><sup>+</sup>-N was calculated as 4.25 kg ha<sup>-1</sup> yr<sup>-1</sup> while that of NO<sub>3</sub><sup>-</sup>-N was as 2.10 kg ha<sup>-1</sup> yr<sup>-1</sup>. VWM concentrations of major ions decreased in the following order NH<sub>4</sub><sup>+</sup> > Ca<sup>2+</sup> > SO<sub>4</sub><sup>2-</sup> > NO<sub>3</sub><sup>-</sup> > K<sup>+</sup> > Cl<sup>-</sup> > Na<sup>+</sup> > Mg<sup>2+</sup>. In this study, relatively high NH<sub>4</sub><sup>+</sup> concentrations in rainwater can be attributed to nearby agricultural activities, excreta and biomass burning.</p><p><strong>Keywords:</strong> Rainwater, Neutralisation, VWM concentration, Agricultural site, Reactive Nitrogen.</p>

Measurement report: Chemical characteristics of PM_2.5 during typical biomass burning season at an agricultural site of the North China Plain

Biomass burning activities are ubiquitous in China, especially in northern China, where there is a large rural population and winter heating custom. Biomass burning tracers (i.e., levoglucosan, mannosan and potassium (K+)), as well as other chemical components, were quantified at a rural site (Gucheng, GC) in northern China from 15 October to 30 November, during a transition heating season, when the field burning of agricultural residue was becoming intense. The measured daily average concentrations of levoglucosan, mannosan and K+ in PM2.5 (particulate matter with aerodynamic diameters less than 2.5 µm) during this study were 0.79 ± 0.75, 0.03 ± 0.03 and 1.52 ± 0.62 µg m−3, respectively. Carbonaceous components and biomass burning tracers showed higher levels during nighttime than daytime, while secondary inorganic ions were enhanced during daytime. An episode with high levels of biomass burning tracers was encountered at the end of October 2016, with high levoglucosan at 4.37 µg m−3. Based on the comparison of chemical components during different biomass burning pollution periods, it appeared that biomass combustion can obviously elevate carbonaceous component levels, whereas there was essentially no effect on secondary inorganic aerosols in the ambient air. Moreover, the levoglucosan / mannosan ratios during different biomass burning pollution periods remained at high values (in the range of 18.3–24.9); however, the levoglucosan / K+ ratio was significantly elevated during the intensive biomass burning pollution period (1.67) when air temperatures were decreasing, which was substantially higher than in other biomass burning periods (averaged at 0.47).

Dissolved organic carbon and nitrate flows in two micro-watersheds with different land uses

he impacts of human activities on watersheds can change the quality and possible uses of water resources. In this context, we evaluated the flows of dissolved organic carbon (DOC) and nitrate (NO3) in the surface waters of two micro-watersheds with different anthropic impacts. Water samples were collected from two micro-watersheds with different land uses (regenerated savanna and an agricultural site) from January 2014 to April 2015. In the rainy season, the samples were collected every 15 days, while in the dry season, samples were collected every 30 days. An automatic sampler in the stream collected the composed samples. Water flow was monitored with a sensor that measured the hydraulic load on the sill of the triangular spillway installed in each micro-watershed. The DOC and NO3 contents were analyze via UV-Vis spectrophotometry. The flow was estimated based on the DOC and NO3 flows and concentrations. The DOC concentrations were higher in the Cerrado micro-watershed; however, there was no difference in NO3 concentrations. In both watersheds, there was a significant increase in the concentrations of DOC and NO3 on rainy days, with was more pronounced in the agricultural watershed. The DOC and NO3 flows were higher in the micro-watershed with Cerrado vegetation on days with rain; while on days without rain, there was no difference.

Different Human–Dog Interactions in Early Agricultural Societies of China, Revealed by Coprolite

Dogs served in a variety of capacities in prehistory. After their domestication in Paleolithic hunter-gatherer societies, the emergence of agriculture shifted their partnerships with people. However, the associations between dogs and early farmers are not readily visible in the archaeological record. In the present study, dog coprolites, uncovered from two groups of early agricultural societies in China during the Neolithic Age, the early rice agricultural site of Tianluoshan in the lower Yangtze River, and three early millet-rice mixed agricultural sites of Shuangdun, Yuhuicun, and Houtieying along the middle Huai River, were examined based on the comparisons of lipid and palynological results to reveal different relationships of dogs and humans. The Tianluoshan dogs showed a plant-dominated diet with higher contents of plant sterols and fatty alcohols with longer chain lengths. Dogs may have lived on foraging or been provisioned with refuse for the cleanness purpose. On the contrary, dogs from the sites of Shuangdun, Yuhuicun, and Houtieying showed a meat-dominated diet with higher proportions of animal sterols and short-chain fatty alcohols. It most probably referred to their assistance in hunting and thus being provisioned with meat. Furthermore, activity areas of the dogs also reflect different deployment strategies and agricultural systems, evidenced by pollen spectra from the coprolites. Dogs at Tianluoshan mostly appeared in the rice field area, in correspondence with the labor-consuming rice cultivation as the main targeted resource, showing their participation in daily agricultural activities. On the other hand, high concentrations of pollen from forest and grassland revealed that hunting dogs played a regular role in the early millet-rice mixed farming societies, probably related to the importance of hunting activities in the daily subsistence.