Energy Consumption, Carbon Emissions and Global Warming Potential of Wolfberry Production in Jingtai Oasis, Gansu Province, China

During the last decade, China's agro-food production has increased rapidly and been accompanied by the challenge of increasing greenhouse gas (GHG) emissions and other environmental pollutants from fertilizers, pesticides, and intensive energy use. Understanding the energy use and environmental impacts of crop production will help identify environmentally damaging hotspots of agro-production, allowing environmental impacts to be assessed and crop management strategies optimized. Conventional farming has been widely employed in wolfberry (Lycium barbarum) cultivation in China, which is an important cash tree crop not only for the rural economy but also from an ecological standpoint. Energy use and global warming potential (GWP) were investigated in a wolfberry production system in the Yellow River irrigated Jingtai region of Gansu. In total, 52 household farms were randomly selected to conduct the investigation using questionnaires. Total energy input and output were 321,800.73 and 166,888.80 MJ ha−1, respectively, in the production system. The highest share of energy inputs was found to be electricity consumption for lifting irrigation water, accounting for 68.52%, followed by chemical fertilizer application (11.37%). Energy use efficiency was 0.52 when considering both fruit and pruned wood. Nonrenewable energy use (88.52%) was far larger than the renewable energy input. The share of GWP of different inputs were 64.52% electricity, 27.72% nitrogen (N) fertilizer, 5.07% phosphate, 2.32% diesel, and 0.37% potassium, respectively. The highest share was related to electricity consumption for irrigation, followed by N fertilizer use. Total GWP in the wolfberry planting system was 26,018.64 kg CO2 eq ha−1 and the share of CO2, N2O, and CH4 were 99.47%, 0.48%, and negligible respectively with CO2 being dominant. Pathways for reducing energy use and GHG emission mitigation include: conversion to low carbon farming to establish a sustainable and cleaner production system with options of raising water use efficiency by adopting a seasonal gradient water pricing system and advanced irrigation techniques; reducing synthetic fertilizer use; and policy support: smallholder farmland transfer (concentration) for scale production, credit (small- and low-interest credit) and tax breaks

LCA applied to perennial cropping systems: a review focused on the farm stage

International audienc

Energy flow for integrated apple production in Greece

Integrated production requires constant improvement of methods employed to achieve high fruit quality and yield with minimal inputs. This work was undertaken to evaluate the energy inputs for apple production, to identify the highest energy consuming operations and propose ways to improve them. Integrated production methods were employed during 1999 and 2000 at 26 apple (Malus domestica Borkh.) orchards in Zagora Pelion (Central Greece). The inputs and outputs of major nutrients (only five farms) as well as energy were calculated and mean values are presented. N inputs were five times higher than outputs and reduction in N fertilization can be considered. Total energy inputs were 50.7 GJ ha(-1) and outputs 118.5 GJ ha(-1) (51.6 GJ ha(-1) from fruit). Chemicals (pesticides, fertilizers), use of machinery and fuel were the most important inputs for apple production, while human labor, although intensively used, accounted for small energy inputs due to conversion factor used. Energy outputs could be improved, as the potential for fruit production is higher compared to fruit production of the study years. Energy productivity was calculated (average of the 2 years) as 0.42 kg MJ(-1), energy intensity as 2.50 MJ kg(-1) and energy efficiency (only fruit considered) as 1.0. Thus, energy savings could be obtained without significant yield reduction, mainly through reducing fertilizer inputs (especially N), diminishing pest control applications through proper techniques and improving the farm road network. (c) 2006 Elsevier B.V. All rights reserved