Die Gedankensaat von Forstmeister Dr. h. c. Kieni? im heutigen Waldbau

Ohne Zusammenfassung     

Agricultural practice changes with cultivating genetically modified herbicide-tolerant oilseed rape

To facilitate weed suppression, oilseed rape or canola (Brassica napus) has been genetically modified (GM) over the last two decades to incorporate herbicide tolerance (HT). The introduction of oilseed rape in commercial agriculture raises concerns about potential adverse agronomic and environmental effects linked to both the genetic modification and altered agricultural practice. How will this new crop modify the existing cropping practice? What are the potential agro-environmental implications of its introduction? This paper analyses and schematises recorded and conceivable agricultural practice changes with GMHT oilseed rape introduction and its likely agro-environmental effects. It develops a conceptual systematics of influencing factors, subsequent practice changes and likely agro-environmental effects. The results can be used to design the mandatory monitoring of adverse GM crop effects.     

Development of locally-adapted faba bean cultivars for organic conditions in Germany through a participatory breeding approach

Organic farming requires cultivars that are specifically adapted to this low input cropping system. Hence, organic farmers and scientists joined in a participatory breeding approach to develop region-specific genotypes of spring faba bean for organic conditions in Germany. A set of 49 genotypes with contrasting degrees of heterozygosity and heterogeneity was used in field trials across five locations in Germany during 3 years 2004, 2005 and 2006. The material involved 18 inbred lines, their 18 polycross progenies, one blend of inbred lines, one blend of polycross progenies, one blend of hybrids and ten checks. Inbred lines are uniform, thus giving the option to be specifically adapted; whereas the polycross progenies and synthetics (Syn-1; predicted from the inbred lines and polycross progenies performance) are partly heterogeneous and heterozygous, thus giving the option to evolve. Agronomic performance was assessed and a “personal appreciation” score of the material was assigned to each genotype by each partner. This personal appreciation was strongly influenced by biotic and abiotic constraints faced by the crop in each location and by the expected grain yield of the genotypes. Uniformity was apparently appreciated by organic farmers. In all locations, the highest yielding inbred line yielded slightly better than the predicted highest yielding synthetic. However, this slight disadvantage of the synthetic is very likely to disappear if the synthetic (Syn-1) is propagated during successive generations.     

Diel Foraging Behavior of American White Pelicans Pelecanus erythrorhynchos on Experimental Aquaculture Ponds

Videography and night vision equipment were used to observe the diurnal and nocturnal activities of American white pelicans Pelecanus erythrorhynchos ( N =6) foraging on three experimental (0.04 ha) channel catfish ( Ictalurus punctatus ) aquaculture ponds in March 2001. Captive pelicans spent most time foraging per hour from 1700 through 2300 h (CST). No foraging was observed from 0700 through 0800 h. Fish captures per hour were greatest from 1700 through 1900 h. On average, captive pelicans ( N = 5) consumed 1.0 ± 0.2 kg of catfish per bird per day during the 10-d foraging trial. This consumption corresponds with an average intake of over 60,000 kJ of energy per bird during the trial. Relative to morning hours, the average number of bill dips per min was greater during afternoon foraging bouts. Fish captures per bill dip, however, did not differ among trial hours. Thus, pelicans were observed to increase foraging effort subsequent to 1500 h and thereby consumed 224 to 532 catfish (average = 313 ± 74 fish; N = 4) during the 10-d foraging trial in ponds stocked with approximately 74,000 catfish/ha.     

Acute effects of wood-pulp on sockeye salmon (Oncorhynchus Nerka)

Freshwater suspensions of pulp fiber in concentrations exceeding 1000 ppm at 15°C are acutely lethal to sockeye salmon fingerlings. Limited adaptation of such fish to fiber is possible but injury, at least in the short term, is irreversible. The acute lethality of various toxicants associated with industrial pulps is synergistically enhanced by the presence of fiber, and pulp storage up to 158 days at 15°C had no significant effect on the acute lethality. Highly purified fibers are less toxic in fresh than in sea water. The sensitivity to fiber of fish from two sources did not differ significantly.