Environmental Geochemistry and Health - Several essential nutrients such as Fe, Co, Cu, I, Se, and Zn are vital to grazing cattle as they play a significant role in intracellular enzyme systems,... 相似文献
Regional Environmental Change - This article provides a review of recent scientific literature on social vulnerability to climate change, aiming to determine which social and demographic groups,... 相似文献
In lekking species, females may become sperm-limited when mating with sexually successful males, and this may be exacerbated
by a poor male diet. Polygynous males may also be limited by the amount of accessory gland products (AGPs) they can transmit
to females, which in turn may influence the females’ refractory period and longevity. Here, we tested the effect of male mating
history, larval and adult diet on copula duration, mating intervals, female fecundity, fertilisation success, life span and
likelihood to remate using sexually successful males of the lekking tephritid fly Anastrepha obliqua. Flies originated from either a native or exotic host fruit and were protein-fed or deprived. Male diet and larval host influenced
copula duration, while the time elapsed between matings was affected by the interaction of mating order and male adult diet.
Female fecundity was not influenced by female position in mating order or protein inclusion into the male diet. However, mating
order and male larval diet influenced female fertilisation success. Importantly, as males mated successively they were less
able to induce a refractory period on females, as the last females to mate with a male were more likely to remate and had
slightly longer life spans than the first females to mate with males. These results might be attributed to a decrease in male
AGPs with increasing male mating frequency. We discuss the role of conditional expression of male mating frequency with respect
to A. obliqua’s life history, the trade-off that females face when mating with a successful male, the effect of larval diet on adult sexual
performance and the possibility for sexual conflict to occur due to high male mating rates and fitness costs to females. 相似文献
The acid-base properties of humic acids (HAs) and fulvic acids (FAs) isolated from liquid swine manure (LSM), soils amended with either 90 or 150 m(3)ha(-1)year(-1) of LSM for 7 years, and the corresponding unamended control soil were investigated by a current potentiometric titration method. The non-ideal competitive adsorption (NICA)-Donnan model for proton binding by two classes of binding sites (i.e., carboxylic- and phenolic-type groups) was fit to titration data, and a set of fitting parameters was obtained for each HA and FA sample. The NICA-Donnan model was shown to describe with a great degree of accuracy the behavior of experimental titration datasets, and highlighted important differences in the acid-base properties of the HAs and FAs examined. When compared to the unamended soil HA and FA, LSM-HA and LSM-FA, had smaller acidic functional group contents, larger proton binding affinities of both carboxylic- and phenolic-type groups, smaller heterogeneity of carboxylic-type groups, and smaller, in the case of HA, or similar, in the case of FA, heterogeneity of phenolic-type groups. Amendment with LSM caused a decrease of acidic functional group contents and a slight increase of proton binding affinities of carboxylic- and phenolic-type groups of soil HAs and FAs. Further, LSM application induced a decrease of the heterogeneity of carboxylic-type groups, whereas appeared not to affect substantially the heterogeneity of phenolic-type groups of LSM-amended soil HAs and FAs. These effects were more evident for HAs than for FAs and tended to slightly increase with increasing LSM amendment rate. 相似文献
This paper identifies the literature that deals with adaptation to climate change in the transport sector. It presents a systematic
review of the adaptations suggested in the literature. Although it is frequently claimed that this socially and economically
important sector is particularly vulnerable to climate change, there is comparatively little research into its adaptation.
The 63 sources we found are analysed following an action framework of adaptation. This distinguishes different adaptational
functions and means of adaptation. By an open coding procedure, a total of 245 adaptations are found and classified. The paper
shows a broad diversity of interdependent actors to be relevant—ranging from transportation providers to public and private
actors and households. Crucial actors are hybrid in terms of being public or private. A substantial share of the identified
adaptations follows a top-down adaptation policy pattern where a public or hybrid operator initiates action that affects private
actors. Most of the exceptions from this pattern are technical or engineering measures. Identified adaptations mostly require
institutional means, followed by technical means, and knowledge. Generally, knowledge on adapting transport to climate change
is still in a stage of infancy. The existing literature either focuses on overly general adaptations, or on detailed technical
measures. Further research is needed on the actual implementation of adaptation, and on more precise institutional instruments
that fill the gap between too vague and too site-specific adaptations. 相似文献
The presence of man-made gamma emitting radionuclides in the region within 32km radius of the Ignalina NPP/Lithuania has been investigated during the period 2001-2004, prior to the closure of the first of the two operating RBMK 1500-type reactors. Gamma spectrometric measurements of various terrestrial and aquatic plants as well as of soil samples showed moderate environmental contamination with the fission product (137)Cs and with the neutron activation products (60)Co and (54)Mn. Traces of the activation products (65)Zn and (110m)Ag were found in the nearest vicinity of the NPP. Activity concentrations were inhomogeneously distributed in the area of interest. Moss and algae samples showed the highest uptake of radionuclides. In addition to the gamma spectrometric measurements, the levels of (14)C were determined in the same bio-indicator samples using accelerator mass spectrometry. 相似文献
This paper presents a method for the analysis of socio-ecological patterns of vulnerability of people being at risk of losing their livelihoods as a consequence of global environmental change. This method fills a gap in methodologies for vulnerability analysis by providing generalizations of the factors that shape vulnerability in specific socio-ecological systems and showing their spatial occurrence. The proposed method consists of four steps that include both quantitative and qualitative analyses. To start, the socio-ecological system exposed to global environmental changes that will be studied needs to be determined. This could, for example, be farmers in drylands, urban populations in coastal areas and forest-dependent people in the tropics. Next, the core dimensions that shape vulnerability in the socio-ecological system of interest need to be defined. Subsequently, a set of spatially explicit indicators that reflect these core dimensions is selected. Cluster analysis is used for grouping the indicator data. The clusters found, referred to as vulnerability profiles, describe different typical groupings of conditions and processes that create vulnerability in the socio-ecological system under study, and their spatial distribution is provided. Interpretation and verification of these profiles is the last step in the analysis. We illustrate the application of this method by analysing the patterns of vulnerability of (smallholder) farmers in drylands. We identify eight distinct vulnerability profiles in drylands that together provide a global overview of different processes taking place and sub-national detail of their distribution. By overlaying the spatial distribution of these profiles with specific outcome indicators such as conflict occurrence or migration, the method can also be used to understand these phenomena better. Analysis of vulnerability profiles will in a next step be used as a basis for identifying responses to reduce vulnerability, for example, to facilitate the transfer of best practices to reduce vulnerability between different places. 相似文献
Mapping social vulnerability is a prominent way to identify regions in which the lack of capacity to cope with the impacts of weather extremes is nested in the social setting, aiding climate change adaptation for vulnerable residents, neighborhoods, or localities. Calculating social vulnerability usually involves the construction of a composite index, for which several construction methods have been suggested. However, thorough investigation of results across methods or applied weighting of vulnerability factors is largely missing. This study investigates the outcome of the variable addition—both with and without weighting of single vulnerability factors—and the variable reduction approach/model on social vulnerability indices calculated for New York City. Weighting is based on scientific assessment reports on climate change impacts in New York City. Additionally, the study calculates the outcome on social vulnerability when using either area-based (person/km2) or population-based (%) input data. The study reveals remarkable differences between indices particularly when using different methods but also when using different metrics as input data. The variable addition model has deductive advantages, whereas the variable reduction model is useful when the strength of factors of social vulnerability is unknown. The use of area-based data seems preferable to population-based data when differences are taken as a measure of credibility and quality. Results are important for all forms of vulnerability mapping using index construction techniques.