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The harvested biomass of switchgrass (Panicum virgatum L.) is generally much lower than its potential; this may be due to several factors including not recovering all the biomass at harvest, weed competition, pests, disease and spatial variation of soil features. The objective of this research was to quantify the yield spatial variation of switchgrass and relate it to soil parameters, in a field of about 5 ha, in 2004 and 2005. Several thematic maps of soil parameters and biomass yield were produced using GIS and geostatistical methods. Soil parameters changed consistently within very short distances and biomass yield varied from 3 to more than 20 Mg ha-1. This remarkable variation indicates that the potential for increasing switchgrass productivity is a real prospect. Furthermore, spatial variation of yield showed similar patterns in the 2 years (r = 0.38**), and therefore a major influence of site characteristics on switchgrass yield can be assumed to occur. Significant correlations were found between biomass yield and soil N, P, moisture and pH as well as between soil parameters. Some soil parameters such as sand content showed patchy spatial distribution. Conversely, a reliable spatial dependence could not be identified for other parameters such as P. Further research is needed.

The drought prone North-West Bangladesh is vulnerable to the impacts of climate change, particularly because of less water availability in the dry period and high water requirement for crop production. Improved understanding of recent changes in crop water demand in the dry season is important for the water resources management in the region. A study was carried out to determine the potential impacts of recent climate change during last three decades on trends of water requirements of Boro rice. The reference crop evapotranspiration (ETo), potential crop water requirement (∑ETC), effective rainfall during the crop growing period (ER), potential irrigation requirement for crop evapotranspiration (∑ETC − ER) and net irrigation requirement of Boro rice were estimated using observed daily climate data in the CropWat model for the period of 1980 to 2013 for four North-West districts. Significant decreasing trends of ETo were observed in most of the dry months due to increasing relative humidity and decreasing wind-speed and sun-shine hours. The results showed decreasing trends of potential crop water requirement, i.e. the total crop evapotranspiration (∑ETC), of Boro rice due to decreasing reference crop evapotranspiration and shorter crop growing periods. The variations in trends of potential irrigation requirement for crop evapotranspiration (∑ETC − ER) found among different districts, are mainly linked to variations in trends of changes in effective rainfall. The net irrigation requirement of Boro rice has decreased, by 11% during the last three decades at an average rate of −4.4 mm year−1, instead of decreasing effective rainfall, mainly because of high rate of decrease of crop evapotranspiration (−5.9 mm year−1). Results indicate that a warming climate does not always result in higher agricultural water use and that climate change can also result in reduced water demands because of changes in humidity, wind-speed and sun-shine hours.

The transition to a low carbon future is starting to affect landscapes around the world. In order for this landscape transformation to be sustainable, renewable energy technologies should not cause critical trade-offs between the provision of energy and that of other ecosystem services such as food production. This literature review advances the body of knowledge on sustainable energy transition with special focus on ecosystem services-based approaches and methods. Two key issues emerge from this review: only one sixth of the published applications on the relation between renewable energy and landscape make use of the ecosystem service framework. Secondly, the applications that do address ecosystem services for landscape planning and design lack efficient methods and spatial reference systems that accommodate both cultural and regulating ecosystem services. Future research efforts should be directed to further advancing the spatial reference systems, the use of participatory mapping and landscape visualizations tools for cultural ecosystem services and the elaboration of landscape design principles.

Since 2007, a range of new modeling approaches and tools have been developed for sustainability impact assessment (SIA), but a lack of universal acceptance of SIA tools in applied policy making is observed. The current article gives an overview of experiences from several European and international projects, critically reviews the selected SIA tools and then discusses a number of reasons for the observed disconnect of the tools with the potential users. Largely based on the experiences of the presented SIA tools focusing land use policy advice, a decision tree is designed, which may facilitate an adequate, region and developmental phase specific selection of tool-box components for the development of SIA tools in future. Elements to ensure end-user participation are also integrated in the decision tree in order to increase the likelihood of the tool in applied land use policy advice. In addition, the Challenges in SIA tool development and use are further discussed.

This paper compares the quantity and quality of solid waste obtained from traditional ponds and recirculating aquaculture systems (RAS) for striped catfish and evaluates methane and compost production from these wastes. Striped catfish sludge was collected from four commercial ponds along the Mekong river and from three indoor RAS. The amount of sludge dry matter produced per kilogram of fish in ponds was 6 times higher than that in RAS. However, the concentration of nutrients in solid waste from RAS was much higher, with better compost quality and higher methane yield than that of sludge from ponds. Out of the collected 381 L biogas, the methane yield of striped catfish's solid waste in RAS systems was 201 L per kg chemical oxygen demand (COD). In ponds, the collected 267 L biogas yielded 125 L CH4 per kg COD. The higher methane production from RAS sludge concurred with higher digestibility of COD: 58% for RAS versus 38% for ponds. The quality and quantity of methane from striped catfish sludge were lower than that for other animal manures, and the resulting electricity yield was low. Considering the higher nutrient concentration in RAS-sludge, we recommend the combination RAS and composting in reusing sludge, which is presently the best option for a more sustainable and cleaner striped catfish production system.

Several dairy farms in the Netherlands aim at reducing their environmental impact by improving the internal nutrient cycle (INC) at farm level. Practices to improve nutrient cycling at these INC farms, however, might not only reduce the environmental impact on-farm, but alter also the off-farm environmental impact associated with supply chain processes (production and transport) related to inputs entering the farm, such as purchased feed or fertilizer or the economic or societal performance of these farms. We compared, therefore, a set of sustainability indicators of nine INC farms with a group of benchmark farms, comparable in terms of farm size, intensity and site-specific circumstances. This benchmark group was composed using statistical matching to exclude the effect of these characteristics on economic, environmental and societal performance. Economic indicators used were: farm income per unpaid annual working unit and the costs to revenues ratio. Environmental indicators used were derived from a cradle-to-farm-gate life cycle assessment: land occupation (LO), non-renewable energy use (NREU), global warming potential (GWP), acidification potential (AP) and eutrophication potential (EP), expressed per kg fat-and-protein-corrected milk (FPCM). In addition, we quantified the soil content of organic carbon and phosphorus, and the soil nitrogen supply. Societal indicators used were: payments for agri-environmental measures, grazing hours and penalties for aberrant milk composition. Results showed that INC farms had a lower non-renewable energy use per kg FPCM, higher soil organic carbon content and received higher annual payments for agri-environmental measures, whereas economic and other environmental, societal indicators did not differed. Furthermore, we demonstrated the need for a sound benchmark to assess the effect of INC-farming on the economic, environmental and societal performance. Statistical matching enabled us to define, for each INC farm, a benchmark group with similar farm characteristics, which are known to affect sustainability indicators. Observed differences in sustainability indicators between both farm groups, therefore, truly resulted from aiming at internal nutrient cycling, and not from differences in other farm characteristics.

Abstract The Mediterranean region is one of the most vulnerable regions to climate change. The majority of climate models forecast a rise in temperatures and less rainfall, which have been observed in recent decades. These changes will affect several vegetation properties, especially phenological dynamics and traits, by increasing drought intensity and recurrence. In this climate change context, the present study aims to assess the evolution of vegetation state and its relation with the climate dynamics in the Mediterranean forest region of northeast Tunisia using Land Surface Phenology (LSP) metrics and the vegetation index (NDVI) analysis from 2000 to 2017. To conduct this work, we used precipitation and temperature data from the two closest weather stations and 16-day NDVI composite images from the MODIS satellite source, with 250-m spatial resolution. Three phenological metrics— start of season (SOS), end of season (EOS), and length of season (LOS) — were obtained and compared for different vegetation types. The LSP variation in response to climatic metrics was also analyzed. The results showed that the LSP in our study area changed significantly during the 2000–2017 period, which includes an average 7.8 days delay in the SOS, an average advance in the EOS by 5 days, and LOS shortened by an average 12.8 days. Autumn (Pr_9) and spring (Pr_3 and P3_4) precipitations, as well as maximum temperature (Tx9+10), represent the best climate parameters to explain the changes in LSP. Both the NDVI and SPEI showed a significant high correlation (p

The Vietnamese Mekong Delta (VMD) is one of the world’s most vulnerable deltas to climate change and sea level rise. Adequate understandings of future hydrological changes are crucial for effective water management and risk-proofing, however, this knowledge body is currently very limited. This study quantifies the responses of the VMD’s river flow regime to multiple stimuli, namely future upstream inflow variation, local climate change, and sea level rise. The one-dimensional hydrodynamic model MIKE 11 was used to simulate discharges and water levels across the delta. We developed four scenarios to represent changes in the upstream discharges, precipitation changes and sea level rise, covering the 2036–2065 period. We downscaled climate data and applied three bias-correction methods for five General Circulation Models (GCM), and two Representative Concentration Pathways (RCPs). The climate change projections show similar trends of increasing wet season precipitation and decreasing dry season precipitation. However, cross-scenario variations are sometimes large, depending on the individual GCMs, the RCPs and specific locations. The hydraulic simulation results indicate that, under discharge changes between −20% and +10%, combined with in-delta precipitation variations during the dry season, river discharges at the four representative stations could reduce substantially from −2.5% to −100.2%. During the wet season, the calculated river discharges show increase between 7.3% and 46.7% under four considered scenarios. Substantial changes in the VMD’s river flow regime could have potentially serious implications for water management, especially saltwater intrusion, and therefore calling for timely adaptation measures.