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

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    The research within the scope of which the presented data was generated was part of the funding initiative ‘Knowledge for Tomorrow-Cooperative Research Project in sub-Saharan Africa on Resource, their Dynamics, and Sustainability’ funded by the Volkswagen Foundation. The overall study aimed at investigating the uncertainties in the effectiveness of biological control of stem borers under different climate change scenarios in Kenya and Tanzania. Using the species distribution modelling approach MaxEnt, the research predicts the current and future distribution of three important lepidopteran stem borer pests of maize in eastern Africa, i.e., Busseola fusca (Fuller, 1901), Chilo partellus (Swinhoe, 1885) and Sesamia calamistis (Hampson, 1910), and two of their parasitoids used for biological control, i.e., Cotesia flavipes (Cameron, 1891) and Cotesia sesamiae (Cameron, 1906). Based on these potential distributions and data collected during household surveys with local farmers in Kenya and Tanzania, future maize yield losses are predicted considering three different Global Circulation Models (GCMs) for four different Shared Socioeconomic Pathway (SSP) scenarios (SSP1-2.6, SSP2-4.5, SSP 3-7.0, SSP5-8.5) and two time periods, i.e., 2041-2060 and 2081-2100. A raster in which probability of habitat suitability is separately specified for each grid cell is the immediate output from species distribution modelling with MaxEnt. Probability of habitat suitability for the respective species hereby is expressed as probability value ranging between 0 (unsuitable habitat) to 1 (perfectly suitable habitat). Probability of habitat suitability was modelled for five species for current climatic conditions, as well as for four SSPs and two time periods.

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    The productivity and sustainability of the prevailing crop production systems are being challenged throughout the Indo-Gangetic Plains. Limiting water resources, depletion of soil fertility, social changes and economic developments drive the current modification of the crop portfolio, reflected in its spatial-temporal patterns and of cultivation practices. In Nepal, this concerns particularly the 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 results 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). Inclusion of an aerobic soil phase (e.g. maize instead of rice) resulted in declining soil C and N contents and consequently negatively affected dry matter accumulation and wheat grain yield. Concurrently, the shift from wheat to cauliflower and tomato increased the demand for B and Zn, and these vegetables showed deficiency symptoms at both sites and in both soil types. Particularly the B concentrations in the biomass of non- amendments crops were always below the critical limits of <10 (wheat), 21 (cauliflower) and 23 mg B kg-1 (tomato). In wheat, the application of Zn tended to increase yields under field conditions, while a B application showed no significant effect, irrespective of the site or soil type. On the other hand, biomass accumulation, nutrient uptake, and economic yield of cauliflower and tomato increased with B (and Zn) applications, but response attributes were unaffected by changes in soil aeration status. These responses were generally more pronounced in the lowland than the mid-hill sites, while overall yields of wheat and temperate vegetables were higher in the cool mid-hills than in the subtropical lowland. Despite low application rates of 2.2-4.0 kg ha-1 of Zn or B, positive residual effects on subsequent non -fertilized maize were observed with Zn in the Acrisols and with B in both soil types. Soils in larger parts of Nepal are low in available B and Zn. A shift towards aerobic cultivation in the wet season will reduce soil C and N contents and concomitantly the supply of B and Zn. At the same time, the current shift from wheat to vegetables increases the crops’ demand for B and Zn. While the application of B and Zn fertilizers can moderately improve the performance of the traditional rice-wheat rotation, with a shift towards vegetable cropping, B and Zn applications become imperative to sustain production. Both the public and the private sectors will increasingly be challenged to develop and make available B- and Zn-containing fertilizer formulations that respond to the changing needs of the emerging production systems. These findings are also pertinent in other environments and for other farming communities in the Indo-Gangetic Plains and the Himalayan foot-hills beyond Nepal.

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    As people change their livelihood preferences, they change the way they relate to the natural resources around them. Anticipating and managing these changes, where possible, is a major challenge for sustainable land-use planning and natural resource management. This is most evident in the Amazon, a region of immense biological and cultural diversity but also a region of rapid change and transformation, quickly integrating through transportation infrastructure (roads, harbors, airports, etc.) with other South American regions and the rest of the world. This project analyzes social and ecological change taking place in indigenous settlements of the Amazon region, as they transform their subsistence economies to fit into a western model of living. It uses social ecological systems as a framework to identify and explore the linkages between changes in these two domains, and aims at understanding natural resource management from the perspective of the user and the utilized resource. This, we argue, requires an understanding of collective decision making (governance) of the variations in land and resource use in a community governed in a specific way, and of the response of forests to small-scale human intervention. The way decisions are taken and the way a group of people structure their governance system will affect the ecological system in different ways. We observed fast transformation and diversification of formerly indigenous communities and fast-track integration into western systems of organization resulting in hybrid governance systems with different combinations of traditional and western ways of social organization and resource management. Palms are an ideal study group because their use and ecology is well documented throughout the region and have more recently become an important source of income for many Amazonian populations. Changes in the management of three utilized palm species served as indicators of change in the social ecological system. We investigated palm abundance and management in the three land-use categories: cultivation areas, moderately disturbed forest, and low disturbance forest. Palms are not sown from seed or transplanted into cultivation areas rather they are passively cultivated (protected from fire, weeds, pests, falling branches, etc.). Although palm species are appreciated either for commercial or domestic purposes, seldom did we observe or document active cultivation taking place. In forested areas the most abundant of the three, Socratea exorrhiza, recognized as a generalist or oligarchic species, showed a positive response to moderate levels of human intervention. The second most abundant species, Astrocaryum chambira, is a near generalist, with more restrictions for its dispersion and establishment than S. exorrhiza, and therefore a less favorable response to moderate levels of intervention. Abundance of Phytelephas macrocarpa was the lowest; as a soil specialist its distribution is uneven and its overall response to intervention most difficult to assess. Changes in palm management betrayed a general shift from a view of cultivation areas as the community’s pantry to a view of cultivation areas as the sum of individually owned plots where only commercially valued species are harvested. The distinction between the three zones was blurred in the community with greater access to the west, there was a pressure towards privatization, to erase the traditional zoning regulations, since both palms and land are seen as a commodity. Indiscriminate extraction is taking place in forested areas and in cultivation areas pressure and conflicts are increasing and leading to formalization of property rights and new forms of representation, thus pushing integration further. Transportation infrastructure will continue its expansion, the pressure for oil and mineral extraction will increase in the Amazon and it will be necessary to accept and understand these paths of change in order to minimize the negative consequences that they might have for the social ecological system as a whole.

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    This part project gathered information on the abundance and structure of three utilized palm species populations around two human settlements in North-west Amazonia, the southern Colombian Amazon region. We collected information on the size of all palm individuals in 3ha of low disturbed forest and 3ha of moderately disturbed forest around each community. These two forest categories were defined using satellite image analysis distinguishing areas with high soil humidity and vegetation cover (low disturbed areas) which were furthest away from the human settlement and used occasionally for hunting. Areas with lower soil humidity and vegetation cover (moderately disturbed areas) were closer to the community and were often used for selective timber extraction.

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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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    The data was collected for doctoral research on sustainable agricultural sustainability in Ntcheu district of Malawi. The data was collected from 238 farming households and from their 450 plots. Data includes livelihood assets, agronomic practices and productivity. A Land productivity potential was estimated using soil fertility and topography. Soil data was extracted from digital soil map by Mponela P., Snapp S., Villamor G. B., Tamene L. D., Le Q. B., & Borgemeister C. (2020). Digital soil mapping of nitrogen, phosphorus, potassium, organic carbon and their crop response thresholds in smallholder managed escarpments of Malawi. Applied Geography. The topographic layers were extracted the STRM-DEM 30m resolution. The data is used in the thesis to estimate the impact of agricultural subsidy policy on farmer behaviour, productivity and nutrient balances and simulations of alternative subsidy policies are projected for the 20-year period from 2017.

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    A total of four field experiments was conducted in farmers'fields in 2013 and 2014 at Tram Kak and Prey Kabas district, Takeo province of Cambodia.

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    To support farmer’s decision making regarding soil management, the main objective of this study is to understand the patterns of spatial variability of the soil properties of the deposit areas that might affect plant growth and crop productivity. For this purpose, soil samples were taken from 310 locations distributed in four reclamation areas of 50 ha each established in 2014, 2010, 2006 and 2002 in El Bagre, Antioquia.

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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.

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    The Upper Kharun Catchment (UKC) is one of the most important, economically sound and highly populated watersheds of Chhattisgarh state in India. It covers diverse land use types: urban, rural, agricultural, forest and industrial areas. The study area is a part of the newly formed state, which was established in 2000 and is characterized by considerable population growth and expansion of urban areas, industrialization, and irrigation areas and facilities for meeting the increasing food demand. Furthermore, the government has planned the formation of the new capital city. The planning unit is partly in the study area, and hence there is an urgent need to estimate the impact of future land use change on the water resources of UKC, and to consider whether and to which degree the intensification of irrigated agriculture is putting the groundwater resources of the UKC at risk of over-exploitation that might lead to a major water crisis in near future. Climate change is likely to severely affect the surface and groundwater resources due to changes in precipitation and evapotranspiration and their spatio-temporal distribution. The impact of future climate change may be felt more severely in the study area, which is already under stress due to the current population increase and associated demands for energy, freshwater and food. In spite of the uncertainties about the precise magnitude of climate change and its possible impacts, particularly on regional scales, measures must be taken to anticipate, mitigate and/or adapt to its adverse effects on surface and ground-water availability. There is no research documented in literature related to climate change and land use change impacts on water resources of the UKC. Hence, an attempt is made to overcome these shortcomings and to run the model SWAT with high resolution input data taking irrigation issues relevant in the UKC explicitly into account. For this purpose, the climate scenarios of the PRECIS regional climate model were bias corrected to station level, and land use maps of 1991, 2001, 2011 and 2021 were prepared with details of surface and groundwater-irrigated areas. The results of the study provide the base for framing strategies for water resource management in the study area. The main findings show that the overall rainfall trend for the UKC increased at a rate of 1.94 mm per annum at p=0.033 level of significance from 1961-2011. No statistically significant change in rainfall in the month of peak rainfall was observed. Mid July remains the period of peak rainfall over the years (1961-2011). There was no significant trend for mean annual temperature. However, slight increase in temperature was detected in specific months. The bias-corrected PRECIS RCM scenarios show an increasing trend for both mean annual rainfall and temperature (except for the q0 and q1 scenarios for the 2020s, where there is a decrease in annual rainfall compared to the baseline). The mean monthly rainfall increases for all scenarios, except for the month of June, where a significant decrease in rainfall is predicted. The main land use change pattern between 1991 and 2011 shows a significant increase in urban areas by 4.67%, decrease in wasteland by 3.76%, increase in area under two-season crops by 5.43 %, while 5.67% of the area is under more than two-season crops with paddy as a summer crop. The two and more than two-season crops are irrigated by groundwater sources. The land use scenario of 2021 shows a further increase in built-up area by 2.6% compared to 2011. Also, the groundwater-irrigated area with two-season crops is expected to increase by 24.25% and the area with more than two-season crops with summer paddy by 12.57%, which indicates an excessive increase in groundwater irrigation for some villages in the UKC and unsustainable use of the precious groundwater resources. On the UKC scale, the impact of land use change on different water balance components is small. There is a decreasing trend of annual discharge, water yield and groundwater contribution to streamflow, and an increasing trend of annual surface runoff and actual evapotranspiration over the decades. The impact on water resources is significant and clearly visible at sub-catchment level, where an increasing trend for urban areas can be observed. Based on the bias-corrected climate scenarios q0, q1 and q14, changes in the main water balance components were simulated with the SWAT model. The simulated annual discharge for the 2020s ranged between 25.9% decrease to 23.6% increase depending on the PRECIS scenario. For the 2050s, discharged ranges between 17.6% decrease to 39.4% increase, and for the 2080s an increase in the range of 16.3% to 63.7% is simulated. The annual surface runoff for the 2020s ranges between 28.8% decrease to 26.8% increase. For the 2050s, predictions vary between 17.9% decrease to 44.1% increase, whereas for the 2080s an increase in the range of 19.5% to 69.6% is expected. The annual percolation for the 2020s is estimated to range between 12.8% decrease to 8.7% increase. Predictions for the 2050s range between 10.3% decrease to 15.4% increase, and for the 2080s between 0.3% decrease and 13.7% increase. The annual groundwater contribution to streamflow for the 2020s is expected in the range of 7.0% decrease to 14.7% increase. Predictions for the 2050s range from 13.3% decrease to 64.7% increase, and for the 2080s between 10.4% decrease and 59.1% increase. Scenario Q1 shows a decrease in annual groundwater quantity in all time steps.