Agroecosystem energy transitions: exploring the energy-land nexus in the course of industrialization

Regional Environmental Change -     

Methodological Development of an Index of Coastal Water Quality: Application in a Tourist Area

With the aim of obtaining an index of coastal water quality, a methodological procedure based on numerical classification and discriminant analysis is presented. The procedure was applied to nutrient data (ammonia, nitrite, nitrate, and phosphate) analyzed along the coastal waters of a Spanish tourist area. Using numerical classification, three levels of nutrient loading were revealed, characterizing oligotrophic, mesotrophic, and potentially eutrophic waters. Discriminant analysis was shown to be an effective methodological tool in the discrimination between trophic groups. For every group, the discriminant procedure generated the centroids. The centroids representing oligotrophic and potentially eutrophic conditions were used to establish the two extremes of the continuum of mesotrophic conditions in these coastal waters: Standardizing values from -1 to 1, the centroids for oligotrophic and potentially eutrophic waters yielded an interval that defined the range of mesotrophic conditions. This interval is proposed as a water quality index. The ability of the coastal water quality index to successfully predict mesotrophic conditions was proved with random samples.     

Assessment of Metal Contamination in Doñana National Park (Spain) using Crayfish (Procamburus Clarkii)

Water quality assessment in the Aznalcollar area was attempted using multivariate methods based on heavy metal concentrations in red swamp crayfish (Procamburus clarkii). Trace levels of four heavy metals, copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), were detected in crayfish from eleven different stations. Principal component analysis (PCA) highlighted a gradient of contamination between the sampling stations. Cluster analysis (CA) distinguished three groups of stations. Discriminant analysis also differentiated three groups. The group centroids of the first discriminant function were used to devise an index that varies according to the source of the crayfish. These standardized values are proposed for use as a water quality index. The ability of this index to successfully predict environmental quality was proved with random samples.     

Analysis and residue levels of forchlorfenuron (CPPU) in watermelons

This paper describes the application of liquid chromatography-tandem mass spectrometry (LC/MS-MS) for analysis of residues of forchlorfenuron (CPPU), a new plant growth regulator, in watermelons, after a sample preparation step based on the buffered Quick, Easy, Cheap, Effective, Rugged and Safe extraction method. Analytical determinations were carried out in a triple quadrupole system fitted with an electrospray interphase operating in the positive ionisation mode (ESI+). Three simultaneous MS-MS transitions of the quasi-molecular ion m/z 248 (precursor ion) were monitored for data acquisition (248 > 129, 248 > 155, and 248 > 248), using the transition 248 > 129 for quantitation. Recovery studies on watermelons at levels of 1-200 microg/kg, performing five replicates at each level and using bracketing single-level calibration with matrix-matched standards for quantitation, gave forchlorfenuron mean recoveries ranging from 82 to 106% with relative standard deviations (RSD) lower than 18%. The limit of determination was established at 1 microg/kg. The method was applied to evaluate the persistence of forchlorfenuron residues in watermelons grown in plastic greenhouses, after applying an individual spray treatment to the flower ovary at the anthesis stage (45 mu g/flower and 60 mu g/flower for cv "Extazy" and cv "reina de corazones" watermelons, respectively). One month after treatment, 20 "Extazy" watermelon units (1.5-2 kg/unit) and 20 "Reina de corazones" watermelon units (4-5 kg/unit) were collected and analyzed individually. None of the samples contained forchlorfenuron residues higher than 1 microg/kg.     

How changes in diet and trade patterns have shaped the N cycle at the national scale: Spain (1961–2009)

During the last five decades (1961–2009), Spain has experienced a considerable expansion in the nutrient cycle of its agricultural sector and, in particular, a threefold increase in anthropogenic reactive nitrogen inputs, from 536 Gg N year^?1 in 1961–1965 to 1673 Gg N year^?1 in 2005–2009. Import of feed (soybean, cereals, and cakes) from America and Europe to supply a growing livestock population constitutes the largest share of this increase, along with intensification of synthetic fertilizer use. While in the early 1960s, Spain was nearly self-sufficient in terms of food and feed supply, the net import of agricultural products presently equals domestic crop production, when expressed in terms of nitrogen content (ca. 650 Gg N year^?1). The most important driver of this shift appears to be the rapid change in domestic consumption patterns, which evolved from a typical Mediterranean diet to an animal-protein-rich diet similar to the North European and American diets. Besides livestock production mostly for national consumption, the Spanish agricultural system has specialized in vegetal products with low N content such as olive oil, wine, vegetables, and citrus fruit, which are for the most part exported. The nitrogen load exported outside the Spanish borders by rivers is very low (6.5 % of the total net N input). As a result of the high import and low export of reactive nitrogen, the Spanish mainland is suffering from considerable pollution by local emissions of reactive nitrogen forms to air and water.     

An interdisciplinary assessment of private conservation areas in the Western United States

Conservation easements are the fastest growing private conservation strategy in the United States. However, mechanisms to assess private land conservation as well as their support by the general public are not well understood. This study uses the ecosystem services framework for assessing existing private lands in Idaho and identifies areas for future conservation easements. Using conservation targets of the land trust as a guide for selecting ecosystem services, we (a) mapped the spatial delivery of conservation targets across public and private lands, (b) explored public awareness in terms of social importance and vulnerability, and (c) mapped future priority areas by characterizing conservation bundles. We found that public lands provided the highest levels of conservation targets, and we found no difference in conservation target provision between private areas and conservation easements. The spatial characterization of conservation target bundles identified potential future priority areas for conservation easements, which can guide planning of land trust conservation efforts.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01323-x) contains supplementary material, which is available to authorized users.     

Analysis and residue levels of forchlorfenuron (CPPU) in watermelons

This paper describes the application of liquid chromatography-tandem mass spectrometry (LC/MS-MS) for analysis of residues of forchlorfenuron (CPPU), a new plant growth regulator, in watermelons, after a sample preparation step based on the buffered Quick, Easy, Cheap, Effective, Rugged and Safe extraction method. Analytical determinations were carried out in a triple quadrupole system fitted with an electrospray interphase operating in the positive ionisation mode (ESI+). Three simultaneous MS-MS transitions of the quasi-molecular ion m/z 248 (precursor ion) were monitored for data adquisition (248 > 129, 248 > 155, and 248 > 248), using the transition 248 > 129 for quantitation. Recovery studies on watermelons at levels of 1–200 μ g/kg, performing five replicates at each level and using bracketing single-level calibration with matrix-matched standards for quantitation, gave forchlorfenuron mean recoveries ranging from 82 to 106% with relative standard deviations (RSD) lower than 18%. The limit of determination was established at 1 μ g/kg. The method was applied to evaluate the persistence of forchlorfenuron residues in watermelons grown in plastic greenhouses, after applying an individual spray treatment to the flower ovary at the anthesis stage (45 μ g/flower and 60 μ g/flower for cv “Extazy” and cv “reina de corazones” watermelons, respectively). One month after treatment, 20 “Extazy” watermelon units (1.5–2 kg/unit) and 20 “Reina de corazones” watermelon units (4–5 kg/unit) were collected and analyzed individually. None of the samples contained forchlorfenuron residues higher than 1 μ g/kg.