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Center for Development Research, Department Ecology and Natural Resources Management (ZEF C), University of Bonn

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    The vegetation survey was performed in 21 circular plots of 10-m radius (250 m2) distributed as follows: 2 plots located in the area undergoing revegetation since 2014, 2 plots on the area undergoing revegetation since 2010, 6 plots on the area undergoing revegetation since 2006, and 11 plots on the area undergoing revegetation since 2002. Trees with diameter at breast height in the range of 2.5 – 10 cm were measured within the plots. In total, 717 trees were selected for measurement of diameter at breast height, wood density, total height and species identification. The coordinates of the center of each plot were recorded using a portable GPS (Garmin eTrex 10, Germany). The angle and distance of each tree from the center of the plot were measured, and its coordinates estimated. Stem diameters of all trees within the plot were measured using a calliper. Tree height was measured using a Vertex IV (Haglöf, Sweden). Crown diameter was measured in north-south and east-west directions. For species identification, a preliminary analysis of the flora of the area was performed following the guidelines developed by Idárraga-Piedrahita et al. (2011), Cardona et al. (2010) and Cardona et al. (2011). For the identification of the trees, leaf samples were collected from all individuals. The samples were preserved in alcohol for transportation to the laboratory, and subsequently dried and visually matched with species of the herbarium of the National University of Colombia. Some species could only be classified by genus because their reproductive morphology could not be determined, which is specifically relevant for the identification of Vismia sp. (Hypericaceae), Casearia sp. (Salicaceae), Cordia sp. (Boraginaceae) and Licania sp. (Chrysobalanaceae). Due to the complexity of their morphological and reproductive characteristics, genera Inga sp. (Fabaceae), Citrus sp. (Rutaceae), Ficus sp. (Moraceae) and Piper sp. (Piperaceae) were not classified at the species level. Herbaceous aboveground biomass growing spontaneously within the area and that was located outside of areas with forest cover was harvested at ground level in 120 plots (4 m2 each) with 30 plots per area undergoing restoration since 2014, 2010, 2006 and 2002. The total fresh weight of the biomass was determined in the field, and a subsample of 500 g was oven-dried for 24 – 48 hours for determination of dry weight.

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    Household surveys were conducted in 251 households to ascertain the local knowledge and practices of indigenous Tagbanua non-honey hunter gatherers. Majority of the 251 households we interviewed use honey as food, medicine, and material. In addition, NDVI values of the household and nesting areas were analyzed in relation to the natural resource management practices of the community.

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    In Nepal, rice-wheat annual double cropping system, which is the dominant food crop rotation in both the subtropical lowland as well as the temperate Himalayan mid-hills of Nepal. As a result of continuing urbanisation and shifting consumer preferences, a drive to replace of wheat with high-value vegetables during the cold dry season is gaining momentum, in the peri-urban fringes; simultaneously, emerging water shortages are preventing permanent soil flooding during the monsoon season, leading to partial substitution of lowland rice by less water-consuming upland crops. Such system shifts and associated changes in soil aeration status are altering the nutrient availability, while increasing the crop demand for the critically limiting micronutrients boron (B) and zinc (Zn). Therefore, compared the B and Zn levels in the traditional rice- based system (under anaerobic condition), in the water-saving maize-based system (aerobic conditions) with both conventional winter wheat and the emerging vegetables as rotation crops. Under controlled conditions in a dysfunctional greenhouse and under field conditions at two representative production sites and soil types (e.g. Acrisols in Kavre in the mid-hills of Nepal and a Fluvisols in Chitwan in the lowland), determined were(1) differential effects of system shifts on the soil supply and crop demand of B and Zn (diagnosis trials), (2) the effects of applying mineral B and Zn fertilizers on yields and economic returns of wheat vs. cauliflower and tomato (response trials), and (3) longer-term carry-over effects of a one-time application of soil B and Zn on biomass accumulation and nutrient uptake by maize (residual effect trials). Plant and soil nutrient was analyzed by Stata version 14.2.

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    Alluvial gold mining generates a vast amount of extractive waste that completely covers the natural soil, destroys riparian ecosystems, and negatively impacts river beds and valleys. Since 2002, a gold mining company has striven to create agroforestry plots in the waste deposits as a post-mining management approach, where agricultural crops and livestock are combined to complement reforestation in the area. This research aims at supporting reclamation of waste deposits by providing a comprehensive understanding of processes to manage the transition of nutrient-poor and acidic deposition sites towards productive agroforestry-based systems. Major components of this research comprise (i) an analysis of environmental and social challenges of the gold mining sector in Colombia, and its potential opportunities to add value to affected communities, (ii) an assessment of management practices and decision-making processes of the farmers working on reclamation areas, (iii) an analysis of the sources of variability of waste deposits from the perspective of soil development and vegetation succession, (iv) an analysis of spatial variability of the physicochemical properties of waste deposits with a spatially explicit management scheme, and (v) an assessment of vegetation recovery in terms of biomass and plant community composition. Farmers who are currently working on areas undergoing reclamation rely mostly on their own local knowledge to respond to the challenges that the heavily disturbed conditions of the area pose to crop establishment. Therefore, increasing their awareness of the inherent heterogeneity of their fields, as well as the interdependencies between management practices and improvement of soil fertility, may increase the productivity of their farms. The analysis of sources of variability of the waste deposits generated by alluvial gold mining revealed that these deposits are primarily influenced by the parent material of the alluvial gold deposits and by the technology used for gold mining (bucket or suction dredges), which define the type of deposit formed (gravel or sand). Waste deposits can provide essential functions for rural areas such as woody biomass production and crop establishment if deposits are managed according to a specific purpose, and crop selection for each deposit is done based on physicochemical and structural soil properties. This finding is echoed by the spatial assessment of vegetation reestablishment through the combination of remote sensing with machine-learning techniques that show a high spatial variability of textural properties and nutrient contents of the deposits. A management approach is proposed with the use of delineated management zones, which can lead to an overall increased productivity by developing strategies suitable to the characteristics of each field and its potential uses.

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    Trees inside one-heactare plots in Bolgatanga Municipal and Bongo districts were measured and identified. Selection of the plots was done randomly trying to spread them over the different parts of the region and represent the main land use types. Allometric measurements of trees - DBH - Crown diameter - Height Specie identification - Local name - Botanical name - English name Location - GPS record

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    Aldwaik and Pontius developed the intensity analysis, a type of change detection, to quantify the behavior of a categorical variable across several time intervals to measure the degree to which changes are non-uniform at three levels: interval, category, and transition. The data input values for the intensity analysis were obtained from landuse and land cover classification of Lagos. For the landuse maps check "Landuse Map Old Lagos (Nigeria) 2009 and 2015"

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    The survey was disseminated to the global practitioners of Citizen Science using the online application Google Forms, and responses were collected between March and July 2019. The survey was designed to collect data from a wide audience, including practitioners from diverse disciplines, citizen scientists, policy makers and researchers. It explored collaboration of Citizen Science with SDGs regarding organized networks, education, data, and policy cycle.

  • Mineral analysis Dried Black Soldier Fly prepupae and pre-experiment substrates, were crushed using a laboratory blender and then ashed and digested in 6 N HCl. An Atomic Absorption Spectrophotometer (Model AA6300, Shimadu, Japan) was used to analyze the following minerals: phosphorus, potassium, calcium, magnesium, sodium, iron, copper, manganese, cobalt and zinc.

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    In our research we assess the sustainability performance of 400 smallholder farms practicing organic (i.e. certified or non-certified) and non-organic agriculture (i.e. conventional or other) using the Sustainability Monitoring and Assessment RouTine (SMART)-Farm Tool and examine differences between these farm categories using multivariate analyses. We also identify general gaps in sustainability performance for all farms.

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    The Data was collected by an online google form survey between April-July 2018, sent to the network of Regional Centers of Expertise on Education for Sustainable Development. The data were used to analyze the role of these networks for implementation of SDGs, in different levels such as local, national and international. Data were analyses through descriptive statistics and Network Analyses.