ALBERT

Description: This data set describes a survey in which 150 smallholder farming households participated in Karagwe and Kyerwa districts, Kagera region, Tanzania at the beginning of the rainy season between September and November 2017. The survey aimed to identify current uses of farm waste (including crop residues, food and kitchen waste, livestock manure and urine, cooking ash, animal bones, and human urine and faeces) and relate them to the agricultural production. Besides, this holistic survey encompasses gender-based household data. The data refers to two cropping seasons from September 2016 to August 2017 (12 months). The households have been selected after discussion with eight agricultural experts from Tanzania. All households were smallholder farming families in banana-coffee-based farming systems. All farms were affected by the degradation of vegetation and soil resources. They all reported that the productivity of their soils had been declined since they had started farming. None of the farmers applied mineral fertilizer to the soils, and none had received training in sustainable land use management yet, e.g., from a local farmer field school or governmental organization. The data set bases on a questionnaire that contained open and closed questions, a total of 54 questions, on household data, agricultural production and the use of organic farm waste. The original language of the survey was Swahili. If some farmers answered in local Haya languages, the answers were directly translated into Swahili and noted. After surveying, the answers were digitalized and translated into English. The dataset contains 130 quantitative/ qualitative variables. The original survey is attached to this data set. -- The study area is located between 1.0° to 2.1° S and 30.4° to 31.4° E in the Kagera region in NW Tanzania and covers seven wards of the Karagwe district (Kayanga, Nyakahanga, and Ndama wards in the Bugene division; Kituntu, Chanika, and Kihanga wards in the Kituntu division; and Nyaishozi ward in the Nyaishozi division), and six wards of the Kyerwa district (Isingiro ward in the Kaisho division; Kamuli, Kikukuru, and Kimuli wards in the Mabira division; and Nkwenda and Rukuraijo wards in the Nkwenda division). On the hilly terrain of the Karagwe Ankolean System, altitudes vary between 1,200 and 1,650 m above sea level. -- The study region is characterized by a bimodal rain pattern with annual rainfall between 716 and 1,286 mm (on average 982 mm ± 127 mm), and moderate temperatures with minimum mean temperatures between 11.6° C and 16.2° C and maximum between 24.6° C and 28.3 °C (Touber and Kanani, 1996; TMA, 2017). The rain falls during the Masika rainy season from March to May and the Vuli rainy season from October to January.

Description: The water use by short rotation coppices (SRC) has been a focus of ongoing research in the last decades. Nevertheless, investigations that consider site factors and present long-term monitoring of the components of the water balance are rare. This research quantified the tree-based transpiration in the 4th growing season of uncoppiced 1st rotational hybrid poplar stands (Populus deltoides Bart. ex Marsh × P. nigra L. “AF2”) in western Slovakia. The aim of the study was to determine the influence of meteorological and soil-related site conditions on transpiration rates. Three experimental plots were located in the Morava River floodplains, on loamy sand-textured soils with different groundwater accessibilities: higher, low, and fluctuating groundwater level. We measured sap flow (Heat Ratio Method), volumetric water content, matric potential, groundwater level, and meteorological variables throughout the growing season in 2019. The results indicated that transpiration in the three sites was almost constant during that period, which was characterized by distinct conditions. The average cumulative transpiration at the site with a higher groundwater level (1105 mm) was larger than at the site with a lower groundwater level (632 mm) and the site with fluctuating groundwater (863 mm). A principal component analysis (PCA) and correlation analysis identified that the contribution of meteorological and soil-related site variables to transpiration differed among the sites. Soil water availability and groundwater accessibility are critical variables for the water use of poplar SRC. We concluded that the combination of site conditions needs to be reconsidered for the expansion of sustainable short rotation plantations in Europe.

Description: This dataset contains measurements of soil moisture, soil matric potential, soil temperature, groundwater depth, and throughfall from the study area of the project Dendromass4Europe. Three poplar SRC stands were selected according to a gradient of groundwater accessibility: S5-N (higher groundwater level), S4-D (low groundwater level), and S2-F (fluctuating groundwater level). On each of the selected sites one soil profile was excavated and prepared for the installation of soil sensors. The aim of the study was to determine the influence of meteorological and soil-related site conditions on tree transpiration rates in poplar SRC stands. Soil moisture was measured with frequency domain reflectometry (FDR) sensors, with 51 mm rods. Soil matric potential and soil temperature were measured with Tensiomark sensors of a length of 125 mm, with a ceramic head. The soil profiles were excavated on May 2018 and sensors were installed as follows: four pairs of sensors of soil moisture and matric potential at 0.3 m soil depth, three pairs at 0.6 m soil depth, and two pairs at 0.9 m soil depth. In the horizontal plane, the distance between sensors was 0.15 m; the distance between pairs was 0.3 m. At the site with fluctuating groundwater level (S2-F), at 0.9 m soil depth, high gravel content prevented the installation of matric potential sensors. On each site, a groundwater well was excavated at a distance of three meters from the soil pit. The fluctuations in groundwater level were recorded with a KELLER pressure sensor. Throughfall collectors were built at 1 m height above ground. The measurements started in June 2018 (in the case of fluctuations of groundwater level: December 2018) with a resolution of 15 minutes until middle of March 2020 (16.03.2020) and after that with a resolution of 60 minutes until end of May 2022 (31.05.2022).

Description: This dataset contains measurements of sap velocity and sap flow from the study area of the project Dendromass4Europe. Three poplar SRC stands were selected according to a gradient of groundwater accessibility: S5-N (higher groundwater level), S4-D (low groundwater level), and S2-F (fluctuating groundwater level). On each of the selected sites four trees were selected according to the tree diameter at breast height distribution.The aim of the study was to quantify the water use of clone "AF2" on sites with contrasting groundwater conditions. For the sap measurements a SFM1 sap device (Heat Ratio Method) was used at 20-minutes resolution in 2019 and 30-minutes resolution in 2021. In 2019 the sensors were installed in April and the measurements were conducted throughout the growing season until end of September. In 2021, measurements started in July and concluded in September. No measurements were conducted in growing season 2020.

Description: This dataset contains measurements of sap flow from the study area of the project Dendromass4Europe. Three poplar SRC stands were selected according to a gradient of groundwater accessibility: S5-N (higher groundwater level), S4-D (low groundwater level), and S2-F (fluctuating groundwater level). On each of the selected sites four trees were selected according to the tree diameter at breast height distribution.The aim of the study was to quantify the water use of clone "AF2" on sites with contrasting groundwater conditions. For the sap measurements a SFM1 sap device (Heat Ratio Method) was used at 20-minutes resolution in 2019 and 30-minutes resolution in 2021. In 2019 the sensors were installed in April and the measurements were conducted throughout the growing season until end of September. In 2021, measurements started in July and concluded in September. No measurements were conducted in growing season 2020.

Description: This dataset contains measurements of global radiation, precipitation, air temperature, relative humidity, air pressure, wind speed and wind direction from the study area of the project Dendromass4Europe. The aim of the study was to determine the influence of meteorological and soil-related site conditions on tree transpiration rates in poplar short rotation coppices plantations. In June 2018 a meteorological station was installed. The measurements started in June 2018 with a resolution of 30 minutes until end of May 2022 (31.05.2022). Three poplar SRC stands were selected according to a gradient of groundwater accessibility: S5-N (higher groundwater level), S4-D (low groundwater level), and S2-F (fluctuating groundwater level). On each of the selected sites one soil profile was excavated and prepared for the installation of soil sensors. The meteorological station was located southwest from the experimental sites. The distance from the meteorological station to the experimental sites was: 9.56 km to site S5-N (higher groundwater table), 9.82 km to site S4-D (low groundwater level), and 6.57 km to site S2-F (fluctuating groundwater table).