Schwermetallmonitoring mit der Standardisierten Graskultur im Untersuchungsgebiet München

For the pilotproject ?Effect Monitoring — Biomonitoring of Immission Effects in the Testing Area of Munich”, standardized grass cultures were exposed at 19 locations during 10 series for two weeks each. The grass was analyzed for the accumulation of lead, antimony arsenic, cadmium, and copper. Highest accumulation was observed with antimony near traffic situations. The comparison of the results from the different sampling points identifies motor vehicle traffic as the source of antimony. First examinations of brake linings support this conclusion. Lead is only slightly increased near traffic. Immission-caused copper contents in the grass were found near the overhead tramway cables. The accumulation detection limits for arsenic and cadmium were not exceeded at any of the measuring points.     

Reproductive cycle and seasonal feeding activity of the neogastropod Buccinum undatum

The whelk Buccinum undatum L. in the northern Gulf of St. Lawrence has a distinct annual reproductive cycle. The ovary and pallial oviduct of the female, and the seminal vesicle of the male, show parallel development, whereas the testis has an inverse cycle. Thus, at the end of winter when the ovary, pallial oviduct and seminal vesicle reach maximal size, the testis is small and undeveloped, whereas the reverse situation occurs in summer. This is the first report of a totally inverse relationship between the ovary and testis for a marine invertebrate. This unusual pattern is due to the long-term storage of sperm in the seminal vesicle of the male prior to copulation. There is no resting period at the end of oogenesis, but rather renewed ovarian development starts shortly after gamete release. By contrast, in the testis after transfer of sperm to the seminal vesicle at the end of spermatogenesis, there is a distinct period of phagocytosis. Mating begins in mid-May, reaches a peak during June and terminates prior to July. Egg laying begins in late May, reaches a peak in mid-June to mid-July and can continue until late August. Examination of the incidence of individuals with food in their stomachs showed that feeding activity is maximal in late autumn through to early spring and decreases sharply coincident with the onset of breeding in late May.     

The effect of male calling on female locomotor activity of Teleogryllus commodus

Summary The calling song of the -cricket, Teleogryllus commodus, attracts for mating. Both calling and -locomotor activity are under circadian control and the behaviors occur approximately at the same time. Daily playback of calling songs for 3–12 h in constant light failed to entrain -running. Instead, calling acts as an external stimulus which can release -locomotion at any time of the 24-h period, while the clock-induced activity continues to run freely. The stimulatory effect of the calling song causes flexible extension of -locomotor activity, but a subsequent restorative period is necessary. The ecological consequences of acoustical stimulation are discussed.     

Anwendung der Hasse-Diagrammtechnik

Using four dynamic criteria, the following environmental changes were evaluated: Global warming; destruction, of the stratospheric ozone layer; eutrophication and acidification of aquatic ecosystems; photochemical smog; reduction of the available area of agricultural soils; loss of species diversity; consumption of resources; reduction of crop yield; forest decline; noise, and smell. These ecosystem changes, or negative effects, were characterized by four dynamic criteria: 1) Regional importance, 2) extent of alteration, 3) resilience and 4) irreversibility. A multi-criteria assessment, accounting simultaneously for all four criteria, requires a generalized concept of order. Here, the concept of partially ordered sets, visualized by Hasse diagrams, was used to derive a priority list of environmental changes. Highest priority was equally assigned to the loss of species diversity, the consumption of resources and the destruction of the ozone layer. However, these ecosystem changes are incomparable to each other concerning the four criteria used and thus require different management strategies.     

Influence of cultivation and food concentration on body length of calanoid copepods

The cephalothorax length of the marine pelagic Copepoda Acartia clausi Giesbrecht, Temora longicornis (Müller), Centropages hamatus (Lilljeborg) and Pseudocalanus sp. was monitored at 15°C during prolonged cultivation through up to 55 filial generations and at different concentrations of food. The length of T. longicornis decreased considerably during the first 15 generations and remained rather constant thereafter. In the other species, body length increased slightly or remained almost constant. Genetic changes are probably involved. Food concentration influenced body size of all species, particularly C. hamatus, in which 80% of the natural size range may be explained by differences in food concentration. The idea that temperature is a dominant factor in determining the length of copepods should be reconsidered.     

Ecosystem development and natural succession in surface coal mine reclamation

Biotic and abiotic factors involved in surface coal mine reclamation were evaluated on 81 mine sites in Mercer County, Pennsylvania, USA. Soil moisture and organic content were the two most important factors in determining the establishment and growth of vegetation on mined lands. Soil bacteria and fungi populations were also related to these soil conditions, and soil micro-organisms were important in the decomposition of organic materials as well as factors in the rate and type of natural succession occurring on these lands. The succession of native plant species increases the density and stability of plant communities on mined lands. The importance of natural succession in mined-land reclamation and the use of these lands by wildlife is discussed.Supported by Grant-In-Aid, Natural Geographic Society.