Estimating the abundance and diversity of butterflies

Concern about the apparent decline in butterfly populations has led to projects designed to obtain quantitative information on their abundance and diversity. Three methods of sampling communities of butterflies are suggested, and the use of a diversity index, β, is recommended. This index gives an estimate of the probability that an individual sampled at random from a community will be different from the previous individual sampled. Change and stability in diversity can be used as a guide for conservation and management programmes.     

An Experiment to Control Fomes annosus in Second Rotation Pine Crops

Stump removal was found to singnificantly reduce killing byFomes annosus in second rotation crops of pine. Poisoning andgirdling of trees prior to felling and also stump poisoningfailed to control the disease. In this experiment no significantdifferences were detected in the susceptibility of Scots andCorsican pine to attack. Increasing periods of delay beforereplanting resulted in less mortality. An equation is presented,based on factors of the first rotation crop which may be usedto predict losses likely to occur when a site is replanted.Root attack by F. annosus results in reduced growth and yieldas well as mortality. The results from the experiment are discussed in trems of themangement of pine crops attacted by F. annosus in Theford Chase.     

Preliminary observations on the effects of burning on the hemiptera (Heteroptera and Auchenorhyncha) of limestone grassland

Samples of Hemiptera were taken in September 1972, from areas of carboniferous limestone grassland which were burnt in April and May 1972, and from adjacent unburnt areas. Significantly larger numbers of species, of both Heteroptera and Auchenorhyncha, were recorded from the unburnt areas, and the species-diversity of the samples was significantly greater. The effects of burning on individual species are considered in relation to their biology and the effects of other kinds of management. The results are discussed in relation to the management of grassland for the conservation of wildlife, and a short review of the effects of burning on populations of invertebrate animals is made.     

The exploitation of helix pomatia L.

The evidence at present available, although incomplete, gives rise to fears for the future of the edible snail Helix pomatia L. The scale of exploitation is increasing, particularly in Eastern Europe, to meet growing demand, mainly from the West. The growth of legislation to control collecting supports the evidence of declining numbers, but the legislation does not appear to be backed by sufficiently detailed population ecology studies. The need for co-ordinated international action on farming, legislation and ecological study is urged.     

Chemical Control of the Pine Shoot Moth, Rhyacionia buoliana (Denis and SchiffermUller) (Lepidoptera: Tortricidae) in Seed Orchards in Britain

In 1970 and 1971 a high population of Rhyacionia buoliana (Denisand SchiffermÜller), the Pine shoot moth, appeared in aseed orchard of Pinus contorta Douglas ex Loud, in Wiltshire.The opportunity was taken to compare several alternative insecticideswith DDT. Field trials in March and August showed that fenitrothioncan be used as an alternative to DDT to control the Pine shootmoth.     

A comparison of some red and yellow earths in tropical queensland and northeast Brazil

Red and yellow earths are kaolinitic and generally sesquioxidic soils having massive B horizons with porous, earthy fabrics and weak profile differentiation but usually displaying a gradual increase in clay content with depth. They are widespread in tropical Queensland and northeast Brazil where comparable climates prevail although the vegetation is markedly different. Their parent materials are mostly quartzitic sedimentary rocks or unconsolidated sediments and the soils occur in a wide variety of topographic and geomorphic situations. In both regions it is probable that many of the soils have not formed under the present climatic conditions.Profile morphology, drainage, silt and clay contents, clay mineralogy, and soil chemistry have been compared and contrasted between the red and yellow earths within and between the two regions. Canonical variate analysis has shown that, on the basis of surface soil chemical attributes, the red earths can be separated from the yellow earths within each region and that the Queensland soils can be separated from the Brazilian soils.     

Chemisch-mineralogische und mikromorphologische untersuchung einer eutrophen (Ramann-) braunerde des Budapester Hügellandes

In spite of the fact that Ramann's concept of Braunerde was extensively used throughout the world, some pedogenic processes and soil properties which are important for the formation and existence of Brown Forest Soils (eutrophic brown earths) are still not well known. Hence, a soil was investigated which was classified as a “Braunerde” by Ramann in 1909. The main question was, whether there might be soil constituents such as inorganic amorphous substances (allophanes) which are able to stabilize the brown-earth fabric, or to inhibit clay migration. From chemical data as well as from the magnitude of the pH-dependent CEC, it was deduced that there are no appreciable amounts of allophanes within the soil. The fabric, however, seems to be stabilized by colloid-chemical flocculation of the clay particles caused by large amounts of carbonates and silicates deposited with the parent material (loess). The decalcified solum is still rich in silicates, especially sand and coarse-silt-sized micas and feldspars (60–200 and 20–60 μm fractions, respectively). Since - in comparison - loesses and loess-derived soils of the Central German mountain region contain less silicates, mainly in fine and medium silt fractions (2–6 and 6–20 μm diameter, respectively), the coarser-grained silicates were assumed to be important for maintaining the Ca²⁺ and Mg²⁺ saturation of the soil by continuous weathering and thus stabilizing the brown-earth fabric.Although the soil is saturated predominantly with Ca²⁺ and Mg²⁺ ions, clay migration proceeds within the upper horizons. This was shown by calculation of the amounts of clay formed by breakdown of micas originally present in the parent material (“clay formation balance”), as well as by micromorphological studies. Furthermore, micromorphological studies and x-ray diffraction data gave some evidence for the migration of preferably finest grained montmorillonitic clays (smectites) penetrated by organic substances (humus). This kind of “selective clay migration” was assumed to be caused by high Ca²⁺ (or Mg²⁺) concentrations in soil solution required for flocculation of humus-penetrated (humus-coated) smectites. From the occurrence of these “humus-smectites” the possibility was assumed that the soil studied has been developed from a former Chernozem type.Quantitatively, clay migration does not reach the amounts of clay formation (breakdown of micas) accompanied by precipitation of iron oxides on mineral surfaces (“Verbraunung”). Thus, the soil profile visually and macromorphologically clearly exhibits the features of brown earths. On the other hand, however, some clay migration was observed. Hence, the soil was classified as a “brown earth with some clay migration” (“schwach durchschlämmte Braunerde”).Judging from the results of the “clay formation balance” an appreciable pedogenic (autigenic) clay formation from weathering products of feldspars was excluded for the soil studied.