The re-establishment of the large copper butterfly Lycaena dispar batava obth. on Woodwalton Fen National Nature Reserve,Cambridgeshire, England, 1969–73

The Dutch race of the large copper butterfly (Lycaena dispar Haw.), was introduced to Woodwalton Fen in 1927 and with careful management survived until 1969, following an exceptional July flood in 1968 which submerged the food plants, greatly reducing oviposition. This paper records the re-establishment of the butterfly in 1970 from caged stock and the population growth in the following three years in relation to weather conditions and fen management. It is suggested that the insect is not perfectly adapted to a fen environment because it has specialised requirements in terms of size and situation of the food plant. It is at risk from drowning if floods occur before or after the hibernation period and slight changes in the growth form of fen plants, which may overshade the food plant, can influence egg production. Experimental work suggests that when the fen vegetation is modified by cattle-grazing during June and July egg production increases because the food plants are made more accessible to the female butterflies. The heaviest mortality occurs in the period from oviposition to the beginning of hibernation but there is no known management technique which will reduce this. However, after emergence in the spring, protection in muslin cages significantly increases the survival rate. It is estimated that only about 30 ha of the Fen can be maintained in a suitable condition for the butterfly to breed successfully. It seems likely that this is too small an area for the insect to maintain itself without artificial aid such as protection for some of the larvae, creation of germination conditions for the food plant, continuance of a controlled grazing regime and the maintenance of a reserve stock in case re-introduction becomes necessary.     

Factors maintaining species diversity in satoyama, a traditional agricultural landscape of Japan

Satoyama is a traditional agricultural landscape in Japan. It contains many kinds of organisms, including endangered species. Satoyama is composed of several habitat types, including paddy fields, secondary forests, secondary grasslands, ponds, and streams. High species richness has been sustained in most habitats by anthropogenic disturbances of intermediate impact, mainly activities related to agriculture. The variety of habitats and connectivity among them have contributed to the high species diversity within satoyama. These factors allow organisms to move among habitats and use different habitat types to obtain different resources. The connectivity among habitats is often more vulnerable than the specific habitats themselves under anthropogenic influences. In satoyama, species that require connectivity among habitats (e.g., grey-faced buzzard [Butastur indicus] and Genji firefly [Luciola cruciata]) have tended to decrease. The grey-faced buzzard is categorized as a “vulnerable” species in the Japanese Red List. It usually nests in forest trees and forages in habitats such as paddy fields, grasslands, and forests. Its foraging locations shift seasonally depending on food availability. It is thought that the degradation of either paddy fields or forests in a landscape may result in the disappearance of this species. The Genji firefly spends its larval period in stream water, pupates underground along streams, and flies near streams after emergence. This species requires not only the integrity of streams and nearby areas, but also connectivity between these areas. The ecology of these species suggests that the variety of habitats and connectivity among them are critical factors for their survival.     

Differential reaction of Pinus sylvestris, quercus robur and Q. petraea trees to nitrogen and sulfur pollution

Establishment of the Nitrogen Fertilizer Factory in Pulawy, Poland (NFFP) in 1966 resulted in contamination of the environment with nitrogen and sulfur compounds. As a result, radial stem growth declined in Pinus sylvestris and increased in Quercus robur. In this study we explored possible causal agents responsible for differences in pollution response among P. sylvestris, Q. robur and Q. petraea species, including differential uptake of nitrogen oxide pollutants by foliage and nutrient imbalances. We compared trees growing in the vicinity of the NFFP and a control area and found that Q. robur leaves were characterized by a relatively smaller N increase than those of P. sylvestris. It is possible that relatively high accumulation of N by pine could cause metabolic dysfunction in that species. However, differences in the concentration of nitrogen or activity of nitrate reductase did not sufficiently explain observed growth differences among the studied species. It is likely that among the factors contributing to the increased growth of oaks after the establishment of NFFP there is the rapid decline and mortality of pollution-sensitive Scots pine trees, easing competition for light and nutrients in the remaining Quercus trees.     

Current status of two endangered Caribbean rodents

Living rodents of the genus Geocapromys of the hutia family have been known during this century on three Caribbean islands (Walker, 1968). Visits were made in 1974 to Jamaica and Little Swan Island to check the current status of two of these endangered populations. It appears from these field investigations that the Swan Island hutia, Geocapromys brownii thoracatus, has been exterminated from Little Swan Island. The main cause may have been predation by cats introduced in the late 1950s and after. The Jamaican hutia, G. b. brownii, remains in three remote areas of Jamaica. It exists at low population levels which have been much reduced from those occurring 30 years ago. The Jamaican hutias are shy and secretive in habits compared to the undisturbed Bahamian hutias, G. i. ingrahami, of East Plana Cay, Bahama Islands.     

Organic-geochemical Differentiation of Petroleum-type Pollutants and Study of Their Fate in Danube Alluvial Sediments and Corresponding Water (Pančevo Oil Refinery, Serbia)

A review is given in this paper of the up-to-date results observed in differentiation and transformation studies on petroleum-type pollutants in underground and surface waters. Water and particulate matter derived from the locality of Pan?evo Petroleum Refinery, Serbia (River Danube alluvial formations). It was shown that distributions of n-alkanes, steranes and triterpanes, and δ¹³C_PDB values of n-alkanes may successfully be used for qualitatively differentiating the petroleum-type pollutants from native organic matter in recent sedimentary formations. In underground waters, a petroleum-type pollutant is exposed to microbiological degradation which is manifested through relatively fast degradation of n-alkanes. Following an almost complete degradation of crude oil n-alkanes in underground water, the biosynthesis of novel, even carbon-number C₁₆–C₃₀ n-alkanes may be observed. It is shown that the n-alkane distribution observed in a petroleum-type pollutant may depend on the intensity of its previous interaction with water. The fate of petroleum-type pollutants in environmental waters may be predicted through laboratory simulative microbiological degradation experiments by using microorganism consortiums similar to those observed under relevant natural conditions, as well as on corresponding nutrient base.     

Effect of microcrustaceans on blue-green algae in flooded soil

The ostracod Cypris sp., when present in large numbers, prevented the development of inocula of Tolypothrix tenuis and suppressed inocula of Anabaena sp. added to flooded soil. The waterflea Daphnia magna, when present in large numbers, only had a minor influence on the growth rate or extent of development of these algae. Anabaena sp. was less susceptible than T. tenuis to the two microcrustaceans. It is suggested that grazing by certain microcrustaceans may limit nitrogen fixation by algae in flooded rice fields.     

Avoidance response of different collembolan species to Betanal

Laboratory avoidance tests were conducted to assess the behavioural reactions of five common collembolan species (Isotoma anglicana, Heteromurus nitidus, Lepidocyrtus violaceus, Folsomia candida, Onychiurus armatus) towards the herbicide Betanal (active ingredient: phenmedipham) in soil. Betanal exerted a dose-dependent repellent action on all tested species. In the case of O. armatus, the sensitivity of the avoidance test exceeded that of mortality and reproduction tests. It is concluded that, in addition to ecotoxicological tests on mortality and reproduction, a test system for assessing behavioural responses could provide more detailed information on the impact of pesticides and other harmful substances on Collembola.     

Nickel induced hyperglycemia in the freshwater fish,Colisa fasciatus

Effect of nickel sulphate at the sublethal dose of 64 ppm (0.8 of LC50 96 hr) on the blood glucose levels of the freshwater fish, Colisa fasciatus, has been estimated from 3 to 96 hr. The blood glucose level exhibits a steady increase due to Ni toxicity. A maximum increase of 85.08% is observed at 96 hr (P < 0.001). It is suggested that the hyperglycemia in C. fasciatus, caused by exposure to nickel sulphate, is possibly a reflection of stress-induced hormone mediated response. It appears that the blood glucose level is a reliable indicator of Ni toxicity to fish.     

Build up of patches caused by Rhizoctonia solani

Rhizoctonia solani is a complex species that is composed of different anastomosis groups (AG). Although these different AGs show differences in their host ranges, generally R. solani is a phytopathogenic species with a wide spectrum of hosts. It has the ability to grow as a saprotroph, which further complicates its behaviour as a parasite. The losses caused by R. solani are very important and need a sustainable management strategy. The patchy appearance of the disease caused by this pathogen is well-known. The patches show within and between season dynamics. The factors which affect the spread of the disease can be grouped into three main categories: host plant, pathogen and environment. However, each of the categories in its detail may depend on or react with the other categories. There are a number of factors that may be involved in dynamics of patches. These potential mechanisms are discussed. It is essential to know about the mechanisms involved to develop an effective control strategy. Although more work is needed to investigate different mechanisms of parasitism deployed by different AGs in different hosts, it seems that many mechanisms external to the host are operating at the same time which necessitates an integrative research approach to study and control the diseases caused by R. solani.     

Crassula helmsii (T. Kirk) cockayne: Is it an aggressive alien aquatic plant in Britain?

The occurrence of this alien aquatic macrophyte has rapidly increased during the last decade reaching c. 100 sites mainly in England; these range from shallow acidic seasonal pools to small, more alkaline, nutrient-rich lakes. It is frequently dominant and can grow in an emergent form from 0·7m above the water to a submerged form 1·3m in length, to depths of c. 3m. Plant bimass is generally high with little seasonal cessation of growth. The habit is frequently a dense sward growth which smothers out other flora; it is present in c. ten reserves and is causing concern. It is widely available from aquatic suppliers, it has an enormous potential to propagate from small fragments and has a high growth rate. It is associated with soft sediments and possibly iron-rich areas; this is confirmed by growth trials in static water tanks. In flowing water trials, growth was even faster in water velocities up to 0·32 m s⁻¹, indicating its potential—although no river sites in Britain are yet known. Control by physical removal, often recommended, results in numerous propagules and should be combined with a secondary technique. This initial study suggests that this plant will remain a problem and caution is required to prevent its further spread. Studies of techniques for its control are needed.     

Growth promotion of the freshwater microalga Chlorella vulgaris by the nitrogen-fixing,plant growth-promoting bacterium Bacillus pumilus from arid zone soils

Immobilization of Bacillus pumilus ES4 from arid land soils, a plant growth-promoting bacterium and the freshwater, green microalga Chlorella vulgaris enhanced microalgal growth only in the absence of combined nitrogen in synthetic growth medium (SGM), but not in medium with combined nitrogen. B. pumilus was able to fix nitrogen in N-free SGM and its growth yielded an accumulation of ammonium in the medium. On its own, B. pumilus is a poor agent for removing nitrogen and phosphorus from wastewater, while C. vulgaris is a capable microorganism. By jointly immobilizing the two microorganisms, the capacity to remove nitrogen and phosphorus from the medium by the microalgae culture was not enhanced, but, at the cell level, removal of these nutrients was significantly enhanced. It appears that growth promotion induced by B. pumilus on C. vulgaris is related to nitrogen fixation.     

Effect of sodium fluoroacetate (“compound 1080”) on the soil microflora

A range of New Zealand soils, many contaminated by sodium fluoroacetate (“Compound 1080” or NaFA) were examined for micro-organisms capable of defluorinating this animal poison. Species of Pseudomonas and Fusurium capable of growth on NaFA were isolated whilst many other soil bacteria and fungi exhibited defluorinating activity when grown on an alternative organic C source. It was concluded that NaFA has a short biological half-life in the soils investigated.Some NaFA-contaminated soils also contained species of the algae Chlorella and Chlamydomonas which were unaffected by NaFA but growth of a duck weed, Spirodela oligorrhiza, was inhibited 73% in the presence of 5 μM-NaFA.     

Abundance of biogenic structures of earthworms and termites in a mango orchard

A comparative study of the spatial distributions and the quantity of biogenic structures produced by earthworms and termites (Odontotermes nilensis and Ancistrotermes guineensis) has been conducted in a mango orchard at Thiès (Senegal).This study showed that surface biogenic structures may represent a large amount of modified soil (up to 536.5 g m⁻²) which vary depending upon the seasons and the species. Whilst the quantity of casts was independent on the season (178.6 g m⁻²), O. nilensis sheetings fluctuated with the seasons. In addition, we show that the spatial organisation of surface biogenic structures fluctuates with seasons. It displays patches ranging from 5 to 15 m. There is a link between the distribution of earthworm casts and the vegetation. In addition, spatial distribution was also linked to the biology of constructing species. We observed that the A. guineensis’ filling structures were mainly located under the mango trees during the dry season where the stems and the brushwoods were abundant. It appears that the spatio-temporal distribution of the biogenic structures under study depended upon two main factors: season and vegetation. However, depending upon the biology of the engineer, these two factors influenced the spatial distribution of structures in different ways.     

Factors influencing pH in lake water

Using an improved titration technique, Lee and Brosset (1978) have established the presence in a number of lake waters of an acid withk _a = 3 × 10^?4. It is shown that higher concentrations of this acid, which seems to correspond to a functional group of humus, may under certain conditions drastically contribute to the lowering of pH of lake water.     

The effect of Arbuscular Mycorrhizal Fungi (AMF) applications on the silage maize (Zea mays L.) yield in different irrigation regimes

In this study the effect of AMF (Arbuscular Mycorrhizal Fungi) Glomus intraradices on the silage yield of maize (Zea mays L.) under five different irrigation regimes was studied. Plant height, green herbage yield, dry matter yield, leaf, stem and ear ratios were evaluated as yield criteria in the study. It was found that AMF inoculation increased the silage yield in the whole irrigation when compared to those which were not applied with AMF. In addition, it was particularly established that AMF application brought about significant increase even in restricted irrigation conditions in green and dry matter yield. It was also realised that, with AMF application, there was an increase in leaf and stem ratios but a decrease in ear ratios.     

New Zealand's first marine reserve,Cape Rodney to Okakari point,Leigh

New Zealand's first marine reserve, Cape Rodney to Okakari Point, with an area of 500 ha, occupies a portion of the north-eastern coastline centred on a small island. The physical and biological characteristics of the reserve are outlined. It was opened in 1977, twelve years after it was first proposed. The problems encountered and lessons learned from trying to establish a nation's first marine reserve are discussed.     

An Expert Support Model for In Situ Soil Remediation

This article presents an expert support model for in situ soil remediation. It combines knowledge andexperiences obtained from previous in situ soilremediations. The aim of this model is to optimiseknowledge transfer among the various parties involvedin contaminated site management. Structured KnowledgeEngineering (SKE) has been used as a framework formodel development. This approach requires scrutinisingall relevant data to answer questions related to anin situ soil remediation operation. Moreover, itclarifies the roles of the different involved parties.The approach was applied to a chlorinated hydrocarbonpollution at a dry cleaner's. Use of the expertsupport model resulted in the development andselection of a new remediation technique.