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Organic carbon performs essential functions in soils, which act as sources or sinks of atmospheric organic carbon. Agricultural management affects the carbon cycle in the soil, with effects on climate change. One of the crops most vulnerable to climate change is coffee. Brazil is the world’s largest coffee producer, with a predominance of management under a conventional system, with sloping terrain and the absence of conservationist practices. The absence of conservationist practices increases in soil loss rates due to water management and carbon emissions, as well as a reduction in coffee production. This paper intended to estimate soil and organic carbon losses by RUSLE in coffee farms in southern Minas Gerais, south-eastern Brazil. Data were obtained from fieldwork, laboratory analysis, and cartographic products. The results indicated, exclusively for coffee crops, soil and carbon losses between 7 and 32 Mg ha−1 year−1 and 87 and 460kg ha−1 year−1, respectively. However, the highest soil losses occurred on sloping terrains with eucalyptus plantations located downhill, and the lowest losses occurred on flat land with native forests. Organic carbon losses were linked directly to soil losses, as a result from the land practices, slope and agricultural management adopted. These results can be used for the planning and priority definition of areas needing conservationist practices, such as green manuring, planting in contour and maintaining of vegetation between coffee rows, which are already used in some sites of the study area. [ABSTRACT FROM AUTHOR]

Agriculture encompasses both plant growing (agronomy, horticulture, and forestry) and animal husbandry. Aquaculture is the aquatic embodiment of agriculture. Lagoons are the main sources of aquaculture in various countries around the world which especially yield shrimp, finfish, macrophytes, and mollusk. Agricultural effluents are highly affecting the lagoon water quality parameters in Sri Lanka since most of the agricultural farmlands in the country are on coastal landmasses. It leads to the increased risks of lagoon water contamination. Therefore, it is essential to identify the water quality parameters affected by anthropogenic agricultural activities and establish their threshold limits for ensuring the sustainability of lagoons. This study has identified the influential lagoon water quality parameters associated with agricultural effluents using bibliographic references, tested the existing values of the most influential parameters in five Sri Lankan lagoons, and briefly discussed their fate and transport. The lagoon water quality was classified into biological, physical, and chemical parameters and studied for their importance in enhancing the water quality. The overall experimental findings on temperature, turbidity, pH, salinity, DO, BOD, COD, phosphates, nitrates, ammonia content, and faecal coliforms in water specimens suggest that the selected Sri Lankan lagoons are heavily polluted because of the accumulation over the decades from the agricultural lands which worsens even more with this salinity from the seawater when the tide comes in. This paper concludes that there is a growing need for mechanisms that can be used to monitor and apply control measures to effectively manage lagoon water quality not only for the integrity of the lagoon itself but also for the dependent ecosystems both in and out of the lagoon. [ABSTRACT FROM AUTHOR]

Understanding the processes of displacement and redistribution of soil particles caused by different erosion types is considered an efficient sediment management tool in various scales from the field plot to the watershed. The rainfed agriculture practices on high gradient slopes are one of the main sources of accelerated soil erosion due to the disturbance of soil structure by tillage processes. Therefore, the present study aimed to investigate the synergistic effect of rainfed agriculture practices and slope gradient on soil erosion using the activity concentrations of 137Cs fallout in Khamsan experimental watershed, western Iran. The diffusion and migration model was used for undisturbed soils and mass balance equation type II was used for agricultural lands. The distribution map of soil erosion and deposition of the watershed was prepared using 137Cs method and the interactions between rainfed agriculture and slope gradient (as the most effective geomorphological factor) on erosion rate and sediment redistribution were evaluated. The results indicated that the highest rates of soil erosion in rainfed agriculture (11.46 t ha-1 year-1) and rangeland (1.27 t ha-1 year-1) were recorded in the slope gradient classes of 20%-30% and >60%, respectively. In addition, the maximum sedimentation in rainfed agriculture (5.78 t ha-1 year-1) and rangeland (0.89 t ha-1 year-1) occurred in the slope classes of 30%-60% and in >60%, respectively. [ABSTRACT FROM AUTHOR]

Biogradska Gora National Park in Montenegro is part of the Dinaric Mountains mixed forest, which belongs to the montane region of the Dinaric Alps. This paper presents some of the main structural and ecological characteristics of the mixed broadleaved old-growth forest with beech [Fagus moesiaca (Domin, Maly) Czecz.], sycamore maple (Acer pseudoplatanus L.) and European ash (Fraxinus excelsior L.) from the preserve area of the Biogradska Gora. These forest ecosystems are characterized by the high species richness and potential productivity. In the study area, 58 vascular plant species were recorded in 4 sample plots of 0.25 ha each. The average timber volume found in the sample plots was 814 m3/ha. This value is twice as high as that of similar pure beech forests in the same preserve area. The results are confirmed the biodiversity and production potential of mixed broadleaved forests, which rarely occur spontaneously. A better understanding of the processes of the pristine forest ecosystems could form a realistic basis for close-tonature management of similar stands. The obtained data provides overview of the structural characteristics of these forests, which have developed without anthropogenic influence. Exploring the structure of forests in permanent preservation areas could be an excellent basis for close-to-nature forest management. [ABSTRACT FROM AUTHOR]