Birth sex ratios in toque macaques and other mammals: integrating the effects of maternal condition and competition

Mammalian life histories suggest that maternal body condition and social dominance (a measure of resource-holding potential) influence the physical and social development of offspring, and thereby their reproductive success. Predictably, a mother should produce that sex of offspring which contributes most to her fitness (as measured by the number of her grandchildren) and that she is best able to raise within the constraints imposed by her condition, social rank, and environment. Such combined effects were investigated by monitoring variations in body condition (weight) and behavior of female toque macaques, Macaca sinica of Sri Lanka, in a changing forest environment over 18 years. Maternal rank, by itself, had no influence on offspring sex, but did affect maternal body condition. The combined effects of rank and condition indicated the following: mothers in robust condition bore more sons, whereas those in moderate condition bore more daughters, but both effects were expressed most strongly among mothers of high rank. Where the consequences of low rank were felt most acutely, as shown by poor condition, mothers underproduced daughters. Environmental quality directly influenced rank and condition interactions, and thus sex ratios. These relationships, and data from other mammals suggest an empirically and theoretically consistent pattern of sex allocation in mammals. New predictions integrate effects, proposed by Trivers and Willard, that are rooted in male mate competition, which is universal among polygynous mammals, with those of local resource competition (and/or female reproductive competition), which are not universal and differ in intensity between the socioecologies and local environments of different species. Received: 30 May 1998 / Accepted after revision: 29 August 1998     

Erprobung und Erfolgskontrolle eines Phytoremediationsverfahrens zur Sanierung Sprengstoff-kontaminierter Böden

The final article of a series of three evaluates the in situ-remediation of TNT(trinitrotoluene)-contaminated soil from ‘Werk Tanne’. The multidisciplinary approach allows a differentiated assessment. Grading with large-scale machinery leads to a depletion of TNT for almost 90% within the first 6 months, while ADNT(amino-dinitrotoluene)-content decreases more or less steadily over 1,5 years. Grading reduces the heterogenous distribution of the contamination only slightly. Results from field-monitoring and biotest-battery indicate residual toxicities of ecotoxicological relevance and a reduced capacity for biological regeneration, in comparison with the uncontamined site. Mycorrhized plants safe-guard the site and improve the soilecological conditions. Their role in reducing lower level residual toxicity requires further investigation. There is need for future research (1) on the dynamics and mechanisms of the initial decrease of TNT followed by stagnation, (2) on the fate of the primary metabolites, (3) on long-term effects of the phytoremediation, and (4) on the establishment of the complex monitoring for routine work.     

Clean development mechanism: an incentive for waste management projects?

The Clean Development Mechanism (CDM) was introduced by the Kyoto Protocol to provide a financial incentive to establish project activities in developing countries for reducing greenhouse gas emissions while also fostering sustainable development. This article shows that waste management project activities play an important role in achieving the aims of the CDM. It describes how these activities have to prove additionality, how the emission reductions must be calculated and monitored in order to be eligible and in order to lead to Certified Emission Reductions (CERs). The article further provides an analysis about the various challenges that are involved in applying the CDM scheme to waste management project activities, which require a new specific set of technical skills and regulatory standards.     

Schwermetalle in Federn

Results from the literature concerning feathers as a matrix for heavy metal accumulation were presented. Especially problems like the differentiation between endo and exogenous contributions, cleaning procedures or the right choice of feather parts were described. The question of the use of feathers for monitoring air, food or bird contamination is also discussed, as well as the advantages or disadvantages of this matrix in comparison to other methods.     

Effects of an Experimental Enrichment of Instream Habitat Heterogeneity on the Stream Bed Morphology and Chironomid Community of a Straightened Section in a Sandy Lowland Stream

A straightened stream stretch with poor habitat heterogeneity was divided into a “control” section with a low amount of submerged woody debris and an experimentally “wood-enriched” downstream section to study the effect of enhanced habitat diversity on the benthic invertebrate community. The downstream section was enriched by fixing 25 wood packages constructed from 9–10 branches on the stream bottom. Succession processes occurring in the two stream sections were compared by chironomid exuviae drift from July to November 2000 and from April to August 2001. During the first sampling period, more drifting chironomid exuviae (medians of control vs. wood-enriched: 446 vs. 331, no significant difference) and total number of taxa (44 vs. 36, Wilcoxon signed-rank test P = 0.019) were recorded for the control section. Although species compositions of both stream sections were highly similar (Sørensen index: 0.83) the diversity in the wood-enriched section was distinctly lower compared to the control section (Shannon–Weaver index: 1.19 vs. 1.50). During the second sampling period, exuviae numbers remained higher in the control section (median: 326 vs. 166), but total numbers of taxa were nearly equal (51 vs. 49), as well as species diversity (Shannon–Weaver index: 1.67 vs. 1.64). The lower chironomid diversity observed during the first sampling period coincided with a gradual but significant change of the streambed morphology in the wood-enriched section. There, the initially more U-shaped profile (V/U = 0.81 ± 0.37) had turned into a pronounced V shape (V/U = 1.14 ± 0.21), whereas the control section retained its unaltered U shape (V/U = 0.62–0.75). This small-scale study on experimental of woody debris in sandy lowland streams showed that the negative impact of increased hydraulic disturbance of the existing streambed more than outweighed any positive impact resulting from the increase in woody debris.     

解关于河流的一维污染物质迁移方程的有限差分法

一、引言 在非稳态的情况下,我们可以写出在河流中进行一级衰变反应的污染物质迁移方程(1): 一般情况下必须求助于数值方法来解方程(1)。我们推荐两个差分体系,在强烈不稳定的边界条件下,这两个体系都被证明是可靠的。我们选择一个均一的河段与一个可以得到解析解的边界条件作为例证。这样的例子可以用来估算示踪研究的参数和确定事故排     

Allergies to molds caused by fungal spores in air conditioning equipment

People suffering from various symptoms while in air-conditioned rooms often show sensitizations to fungi that can be isolated when the fungi are dremoved from air conditioners. By using specific challenge tests it was shown that fungal spores in air conditioners can evoke allergic symptoms. Hyposensitization was the specific therapy prescribed for such allergic reactions. After hyposensitization therapy, more than 70% of the patients so treated could live and work again in air-conditioned rooms without developing specific symptoms.