Validating Landsat-based landscape metrics with fine-grained land cover data

ContextModerate-grained data may not always represent landscape structure in adequate detail which could cause misleading results. Certain metrics have been shown to be predictable with changes in scale; however, no studies have verified such predictions using independent fine-grained data.ObjectivesOur objective was to use independently derived land cover datasets to assess relationships between metrics based on fine- and moderate-grained data for a range of analysis extents. We focus on metrics that previous literature has shown to have predictable relationships across scales.MethodsThe study area was located in eastern Connecticut. We compared a 1 m land cover dataset to a 30 m resampled dataset, derived from the 1 m data, as well as two Landsat-based datasets. We examined 11 metrics which included cover areas and patch metrics. Metrics were analyzed using analysis extents ranging from 100 to 1400 m in radius.ResultsThe resampled data had very strong linear relationships to the 1 m data, from which it was derived, for all metrics regardless of the analysis extent size. Landsat-based data had strong correlations for most cover area metrics but had little or no correlation for patch metrics. Increasing analysis areas improved correlations.ConclusionsRelationships between coarse- and fine-grained data tend to be much weaker when comparing independent land cover datasets. Thus, trends across scales that are found by resampling land cover are likely to be unsuitable for predicting the effects of finer-scale elements in the landscape. Nevertheless, coarser data shows promise in predicting fine-grained for cover area metrics provided the analysis area used is sufficiently large.     

Resolving the Conflicts Between Biodiversity Conservation and Socioeconomic Development in China: Fuzzy Clustering Approach

Resolving the conflicts between biodiversity conservation and socioeconomic development is a global pursuit for the long-run prospects of the human species. Based on Wenchuan County, a typical county in southwestern China, a group of 20 indicators quantifying regional biodiversity and socioeconomic development was established to classify and evaluate the county area spatially. A fuzzy c-means clustering (FCM) algorithm was used as the classification method. Three indices including BD, DL and DR characterizing the value of biodiversity, the level and rate of socioeconomic development of the delineated regions were formulated. The results indicated that Wenchuan County was optimally classified into 4 types of regions (region I to IV). The area percentages of the regions vary widely from 4.3 to 65.7%. The sequences of the regions on biodiversity, socioeconomic development level, and socioeconomic development rate were, respectively, IV > II > III > I, I > III > II > IV and III >I >II >IV. The spatial strategy on coordinating biodiversity conservation and regional development is to develop mainly from the east(I, II, III) and to conserve mainly in the west(IV). Eco-industry, such as eco-tourism and eco-agriculture, need to be emphasized in the process of regional development. The quantitative methods used here may have a wide applicability.     

Ants resort to majority concession to reach democratic consensus in the presence of a persistent minority

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Effects of emergence phenology, taxa tolerances and taxonomic resolution on the use of the Chironomid Pupal Exuvial Technique in river biomonitoring

1. We studied chironomid communities of four rivers in south‐eastern Finland, differing in their water quality, during summer 2004 using the Chironomid Pupal Exuvial Technique, CPET. The aims of the study were to (i) test the adequacy of the generic‐level identification in the CPET method, (ii) define the emergence patterns of chironomid taxa classified as intolerant to organic pollution, (iii) assess the tolerance levels of intolerant chironomids and (iv) identify taxa most indicative of good water quality. 2. Procrustean rotation analysis indicated very strong concordance between the ordinations using either species or genus‐level data, suggesting that generic‐level identification of chironomids is adequate for biomonitoring based on CPET. However, when only a few taxa occur in great numbers, it may be advisable to identify these to the species level, especially if these taxa are important indicators of the impact in question. 3. The detection of a particular species may require accurate timing of sampling, whereas a species‐rich genus might be detected throughout a season. Given that the emergence of chironomid species may vary from year‐to‐year and between sampling sites, community differences detected at the species level may be related to between‐site variation in species’ emergence patterns rather than true differences in species composition. 4. Indicator species analysis (IndVal) showed that the distribution and abundance of intolerant chironomid taxa differed strongly among the studied rivers. Some of the intolerant taxa were restricted to unimpacted conditions, whereas others occurred mainly in impacted rivers. Thus, the indicator status of some genera (e.g. Eukiefferiella, Parametriocnemus, Stempellinella and Tvetenia) needs reassessment.     

The influence of the spectral composition of irradiance on primary production in the Eastern Scheldt (The Netherlands)

The error inin vivo ¹⁴C incubator measurements of primary production in the Eastern Scheldt when neutral density filters were used and the error obtained when no account was taken of the spectral changes in submarine irradiance that occur with increasing depth, were evaluated theoretically. By multiplying the photosynthetic action spectra of two marine algae by calculated irradiance in the euphotic layer using Kd and Kd() respectively, the gross primary production P[Ed(400–700)] and P[Ed()] was computed. In the green-brown waters of the Eastern Scheldt estuary the use of neutral density filters was sufficient to simulate the underwater light conditions. In clear waters it can cause an overestimation of the gross production.     

Ecology and community dynamics of Kubo people in the tropical lowlands of Papua New Guinea

Kubo producer-units (families and independent bachelors) could have been self-sufficient in the production of bananas but chose not to be. Nor did they seek self-sufficiency in the production of any combination of staple carbohydrate foods (bananas, tubers, sago flour) or, in the long term, strive for balance in the exchange of food with other producer-units. Despite the fact that bananas, which provided 50% of people's energy needs, were a delayed-return crop Kubo communities were very unstable. This instability and the failure to choose the option of self-sufficiency were connected and were mediated through intense intracommunity sharing that, ultimately, served to negotiate a concern with sorcery. The people grew bananas in the way they did, not out of environmental necessity, but to accommodate the crop to the needs of sharing and, thereby, facilitate community living.     

Cyclic behavior of plum curculio,Conotrachelus nenuphar (Herbst) (Coleoptera: Curculionidae), within caged dwarf apple trees in spring

From 12 to 19 May 1987, during Morspur apple bloom, 21 radioactively labeled (⁶⁵ Zn) adult plum curculios, Conotrachelus nenuphar (Herbst), were released within a field cage containing four dwarf apple trees and located three times a day. A technique was developed for quickly obtaining (x, y, z)coordinates of location for adults foraging within apple trees. Cyclic patterns of behavior were detected using spectral analysis procedures. Over 70% of plum curculios exhibited diel periodicity with respect to activity and rate of movement, 36% exhibited such periodicity with respect to presence in the trees, and 27% with respect to movements from the center to the periphery of the canopy. Presence in fruit clusters, height in the trees, and movements along east-west and north-south axes showed little or no periodicity. Factors triggering cyclic behavior and practical implications of the results are discussed.