Manual Clearance Research Articles

Status of forest remnants invaded by tradescantia (Tradescantia fluminensis Vell.) following introduction of biocontrol beetles and manual clearance after three years

ABSTRACT We compared biocontrol beetles and manual clearing of tradescantia in forest remnants invaded by tradescantia (Tradescantia fluminensis Vell.) on the agriculturally modified Hikurangi floodplain, northern New Zealand, to inform best practice in enhancing native biodiversity. Four forest remnant study sites were used: two on dairy farms and two protected in a reserve. We assessed tradescantia biomass and cover as indicators of biocontrol effectiveness in the short term, and composition and seedling establishment for effectiveness in the longer term. We found the biocontrol treatment (a combination of tradescantia beetles Neolema ogloblini, Neolema abbreviata, and Lema basicostata) was slow in reducing tradescantia biomass and had little effect in promoting regeneration of native forest species after 3 years. Beetle feeding damage was significantly higher at the biocontrol sites; however, tradescantia biomass or cover was not significantly lower. Although tradescantia biomass in the biocontrol treatment was decreasing, several more years would probably be required for beetle populations to increase and reduce biomass sufficiently to facilitate survival of native seedlings. Results between sites were variable, although dairy farm sites had overall higher nutrient status with higher total potassium levels, and lower nitrogen/phosphorus ratios, and generally higher tradescantia biomass. Manual clearing (‘handclear’) of tradescantia increased vascular species richness but was much more labour intensive and required ongoing management of resprouts. Handclear plots also had lower soil water content than control (means = 36% dry weight, 49% dry weight, respectively), a wider range of daily temperatures, and high species losses (as well as gains). Species losses were probably exacerbated by the greater environmental extremes caused by removal of the tradescantia living mulch, and the incomplete recovery of ground cover vegetation and microclimate suitable for seedling regeneration. Biodiversity benefits are likely to accrue slowly following the introduction of biocontrol agents; longer-term, these should prove more cost-effective than handclear.

Effect of Manual System in Handling Documents Clearance in and Out Ship Service, Loading and Unloading Ship agency by PT. Bahari Eka Nusantara Sangkulirang branch, East Kalimantan

Bulk ship handling activities cannot be separated from the ship handling service plan, namely the arrival and departure of ships. Before the process of arrival and departure of the ship, several activities are carried out which are determined in advance by the shipping company together with the port manager and must be conveyed to the ship's side. The loading and unloading of ships coming and going, loading and unloading coal, requesting ship needs, handling clearance in and clearance out documents through Syahbandar manually whose service hours are limited, starting from 8 o'clock to 10 pm due to the shahbandar class which is still classified as KUPP class III, and also greatly limiting the movement and service of the ship service served. The purpose of this study is to find out how much influence the management of clearance documents in and out becomes longer, limited operating hours and delays in the loading and unloading process of ships, which are agentized by PT. Bahari Eka Nusantara Sangkulirang Branch, East Kalimantan. The approach method used is a descriptive quantitative method, while the data collection technique uses questionnaires, documentation, observations, and literature studies so that the influence / not between the manual clearance in and out system can be found on the service of the ship being inundated. The results of this study show that there is an influence between the manual clearance in and out system on the service of the ship being inundated.

Typha angustifolia L. Grass Hindering against Agricultural Productivity in Aliero River, Kebbi State, Nigeria

This research work tries to examine the socioeconomic impact of Typha angustifolia L. grass in parts of Kebbi state (Aliero, Kashin Zama and Sabiyal), Nigeria. For better understanding of the field conditions with regards to the impact of the grass on the socioeconomic of the area (agriculture, fishing and the livelihood pattern), two hundred (200) questionnaires were designed and administered, out of which only One hundred and forty five (145) were returned. Findings from the questionnaire survey of some communities along river Aliero (Kashin Zama and Sabiyal) show that, there is general reduction in the flow of water in the river channel over the last few years. This was attributed to blockages by Typha angustifolia L. grass and silt deposits within the river channel. There is also reduced or loss of cultivation of some crops particularly irrigated crops such as millet, maize, rice, wheat and vegetables, fishing activities in the area is also affected by the grass. This situation is worst in Kashin Zama area, where many farmers reported that, before the emergence of Typha angustifolia grass in the area, they recorded 225bags of rice in 10hecter, and now only 60-65 bags where recorded in the same piece of land. Moreover, communities have tried communal and individual manual clearance of the Typha, while Aliero Local Government, Kebbi State and Federal Governments are also carrying out mechanical clearance work in the channel. All these efforts have little impact.

UXO-AID: A New UXO Classification Application Based on Augmented Reality to Assist Deminers

Unexploded ordnance (UXO) is a worldwide problem and a long-term hazard because of its ability to harm humanity by remaining active and destructive decades after a conflict has concluded. In addition, the current UXO clearance methods mainly involve manual clearance and depend on the deminer’s experience. However, this approach has a high misclassification rate, which increases the likelihood of an explosion ending the deminer’s life. This study proposes a new approach to identifying the UXO based on augmented reality technology. The methodology is presented based on two phases. Firstly, a new dataset of UXO samples is created by printing 3D samples and building a 3D model of the object data file with accurate data for 3D printed samples. Secondly, the development of the UXO-AID mobile application prototype, which is based on augmented reality technology, is provided. The proposed prototype was evaluated and tested with different methods. The prototype’s performance was measured at different light intensities and distances for testing. The testing results revealed that the application could successfully perform in excellent and moderate lighting with a distance of 10 to 30 cm. As for recognition accuracy, the overall recognition success rate of reached 82.5%, as the disparity in the number of features of each object affected the accuracy of object recognition. Additionally, the application’s ability to support deminers was assessed through a usability questionnaire submitted by 20 deminers. The questionnaire was based on three factors: satisfaction, effectiveness, and efficiency. The proposed UXO-AID mobile application prototype supports deminers to classify the UXO accurately and in real time, reducing the cognitive load of complex tasks. UXO-AID is simple to use, requires no prior training, and takes advantage of the wide availability of mobile devices.

Reasons for under-reporting of paraquat poisoning in India.

Background Paraquat is an inexpensive herbicide used in agriculture because it is easily available and the cost of labour for manual clearance of weeds is prohibitive. Paraquat is toxic to human beings and is also used for committing suicide. We studied the reasons for under-reporting of paraquat poisoning including those related to the training of doctors. Methods In this mixed-methods study, we describe a series of patients with paraquat poisoning. We recorded their demographic data, clinical features, treatment and outcome with an intention to explore the reason for an initial misdiagnosis. We also explored whether deficiencies in curricula contributed to the misdiagnosis. Results The patients of paraquat poisoning (n=28) were mostly young illiterate men driven by impulsive behaviour rather than chronic depression. Paraquat was consumed by patients from non-agricultural background as well, implying easy access to the poison. Many patients could not name the agent and so initial treatment was directed at organophosphorus poisoning. The diagnostic signs included paraquat tongue, renal failure and jaundice. Most of the casualty medical officers and residents were unfamiliar with the symptoms and signs of paraquat poisoning as was evident by their answers to the questionnaire. Knowledge of medical students about paraquat poisoning was not assessed in the theory examinations and viva. Conclusion Factors contributing to the limitation in establishing the diagnosis are illiteracy and ignorance of the patients, lack of specific signs and lack of training of medical officers in treating patients with paraquat poisoning.

Effect of Invasive Rhododendron ponticum L. on Natural Regeneration and Structure of Fagus orientalis Lipsky Forests in the Black Sea Region

Biological invasions threaten global biodiversity and forest ecosystems; therefore, it is necessary to use appropriate strategies for combating the spread of invasive species. Natural regeneration of eastern beech (Fagus orientalis Lipsky) is considerably limited by an aggressive invasive shrub, pontic rhododendron (Rhododendron ponticum L.), in the Black Sea Region of Turkey. Therefore, the future character of the region’s forests is uncertain. The aim of this research was to evaluate the structure of beech forests with different management regimes of rhododedron and to determine the interaction among tree layer, rhododendron cover, and natural regeneration in Düzce Province using the FieldMap technology. The following variants of forests were compared: without intervention (control) and three and six years after rhododendron clearance. The results showed that tree density ranged between 175–381 trees ha−1 and stand volume between 331–589 m3 ha−1. The horizontal structure of the tree layer was mostly random, and the spatial pattern of natural regeneration was aggregated. Recruit density and height in the beech stands were significantly differentiated due to the influence of presence or absence of invasive rhododendron. Rhododendron cover ranged between 81%–97%, and woody stems amounted to 72,178–86,884 ha−1 in unmanaged forests. Canopy in the overstory did not have a significant effect on the density of regeneration and rhododendron cover. Tree layer had a significant negative influence on natural regeneration within a 4 m radius on the plots without rhododendron. However, on the plots with dense rhododendron cover, tree layer had a positive influence on regeneration within a 1.5 m radius. Natural regeneration density was significantly higher when rhododendron was cleared than the plots without intervention. On the plots without woody clearance, there was an insufficient regeneration (113–619 recruits ha−1); however, they had higher mean height compared to the sites without rhododendron. After three and six years of rhododendron clearance, the numbers of recruits in natural regeneration were 63,981 ha−1 and 105,075 ha−1, respectively. In conclusion, invasive spread of rhododendron was a limiting factor of the prosperous regeneration and tree species diversity, and manual clearance of rhododendron is recommended in managed beech forests of the study region.

Automated assessment of vertical clearance on highways scanned using mobile LiDAR technology

Abstract Assessing vertical clearance at bridges is a preliminary step in most routine bridge inspections. This information is critical when assessing the structural integrity of bridges. Furthermore, clearance information at bridges and other overhead assets on a highway network is also extremely important when routing oversized vehicles on a highway network. Efficient clearance assessment makes critical information readily available to asset owners. As a result, asset owners and transportation agencies are able to address concerns in a timely manner, which would help them avoid prohibitive maintenance costs sustained in case of collisions. Unfortunately, manual clearance assessment using conventional surveying tools is unsafe, time consuming, labour intensive. To overcome these challenges, this paper proposes a novel algorithm whereby mobile LiDAR data could be used to efficiently assess clearance at overhead objects on highways. The proposed algorithm first detects and classifies all overhead objects on a highway segment. The clearance is then assessed at each of those objects and minimum clearance is identified. Detection involves voxel-based segmentation of the point cloud followed by a nearest-neighbour search to locate overhead structures. After detecting the structures and identifying their locations, points representing the same object are clustered and classify into bridges and non-bridges. Furthermore, an estimate of the clearance at each object is also obtained. For objects of long span such as bridges, detailed clearance assessment is performed. The developed algorithm was tested on three highway segments in Alberta, Canada including a 242 km highway corridor. Testing revealed that the method was successful in detecting and classifying all overhead structures at an accuracy level of 97.8% and 96.2%, respectively. The algorithm was also successful in accurately measuring the clearance at those structures with the differences in measurement between ground truth data and the extracted results ranging between 0.03 and 0.47%.

Forest clearance and land use by early farmers in Europe: Insights from north Greek oral history

European prehistorians have long debated whether Neolithic farmers, especially in temperate central and northern Europe, exploited cleared woodland for short-term ‘slash-and-burn’ crop husbandry or for cultivation of ‘permanent’ gardens/fields. Because empirical evidence was scarce and rather indirect, circumstantial arguments based on the relative costs and benefits of the two rival regimes have hitherto dominated this debate, but more direct archaeobotanical proxies for Neolithic crop husbandry (based on weed ecology and crop isotopes) now favour the predominance of intensively cultivated permanent plots. At the same time, it is argued from ongoing experimental cultivation at Forchtenberg in southern Germany that short-term slash-and-burn husbandry offers much better returns on both land and labour, at least on poor soils marginal for Neolithic cereals. This paper presents oral historical evidence for mid-twentieth century clearance and subsequent long-term cultivation of mixed deciduous woodland in the Pieria region of northern Greece. These data extend the sparse European ethnographic and historical record of manual clearance for crop husbandry to deciduous woodland of the northern Mediterranean, while also providing comparative material against which to evaluate experimental results. Pierian farmers achieved good cereal yields for many years on cleared woodland, with very limited use of fire, demonstrating the viability of a permanent-cultivation regime for early farmers in the north Mediterranean, but suitable land was scarce in Pieria and informants had no experience of the alternative slash-and-burn regime. Conversely, the Forchtenberg experiments have effectively tested only the slash-and-burn regime under soil pH conditions hostile to successful long-term cultivation. Evaluation of these experiments in the light of the Pierian data suggests that long-term cultivation of cleared woodland would have offered Neolithic famers better returns than slash and burn under good or neutral soil conditions. Comparison of the likely returns of the two rival regimes thus offers no grounds for questioning archaeobotanical indications of Neolithic permanent cultivation. The Pierian and Forchtenberg data agree, however, in suggesting that the time elapsed between clearance and reliable grain harvests, under either regime, may have been long enough to pose a significant challenge to the survival of pioneer Neolithic farmers, especially if these were colonists settling beyond ‘commuting’ distance from their previous homes.

FIRST EXPERIMENTAL PROTOTYPE OF A MECHANISM FOR POULTRY HARVESTING

Recent study aimed to investigate the poultry harvesting period with engineering approach in an attempt to provide a mechanical prototype for moving poultry from the surface and convey it with belts technique to packing facility without any dangerous or injuries. The study also focused on determine some important dimensional, mechanical and physiological properties for birds under investigation to be as assistant data-bases in design, manufacture and test the proposed prototype. Research work was carried out at two poultry farms, farm of Agric. Fac., Cairo Univ., farm of El-Rabie Poultry Company. Proposed prototype’s dimensions were 210 (cm) length, 90 (cm) width and 100 (cm) high which fit with the entries dimensions of the farms and also able to work inside the houses and to deal with their obstacles. The general manual clearance rate for the crew (CRcrew) was approximately 1540 (bird/hour) and the general manual clearance rate for one man (CRman) was approximately 72 (bird/hour). The bucket’s maximum rate was 525 (bird/min) with respect to definite conditions which are the bucket stay in continues and constant forward movement and with full load condition, also the belt’s maximum rate was 480 (bird/min) with respect to same conditions. The actual packing rate was indicated by 1.5 (drawer/min) and the prototype’s actual overall rate was calculated by an average value of 1350 (bird/hour). The number of heartbeats for birds’ sample was measured in several situations; it was 42-55 (beat/min) before the manual harvesting process, 75-90 (beat/min) after the manual harvesting process and finally it was 69-85 (beat/min) after using the suggested automated prototype. The obvious result was the excellence of the automated method according to the physiological point of view which reflects small stress value. Finally, the overall prototype’s cost (operating and manufacturing cost) indicated by 6450 (LE) and finally the payback period of the investment cost was indicated by approximately 18 (month) depending on savings from labor.

The diversity and abundance of ants in relation to forest disturbance and plantation establishment in southern Cameroon

Summary Tropical biodiversity is seriously threatened by deforestation but few studies have quantified its impact. We aimed to measure the impact of forest clearance and different methods of establishing Terminalia ivorensis (Combretaceae) forest plantations on the abundance, richness and composition of ants, the most abundant group of arthropods in tropical forest canopies, in the Mblamayo Forest Reserve in Cameroon. For canopy ants, we quantified the effects of different methods of plantation establishment by sampling two sets of plots subjected to complete clearance, partial mechanical clearance and partial manual clearance relative to uncleared forest reference plots. For leaf‐litter ants, we quantified the impacts of different levels of forest disturbance along a gradient from near primary forest to complete forest clearance. A total of 97 ant species was recorded from the canopy (from approximately 48 500 individuals), at an average of 213 (±45) ants m−2. Jack‐knife estimates of species richness showed that at one site, Bilik, 87% more species occurred in the partial manual clearance plot than the complete clearance plot, with the partial mechanical clearance plot intermediate. At the other site, Ebogo, ant richness did not vary between treatments. Ants were 20 times more abundant in the partial manual clearance plot in Ebogo than the partial manual clearance plot in Bilik, largely due to a numerous Technomyrmex species that might have reduced ant richness on this plot. Cluster analysis of the similarities in ant species composition between plots, calculated by the Morisita index, showed that site and treatment affected species composition. Neither treatment nor site affected the relative number of species in different nesting categories. A total of 111 ant species (from 3650 individuals) was recorded from the leaf litter, at an average of 52 (±4·6) ants m−2. Species numbers were greatest in the two partial clearance plots in Ebogo (52–53 species), lowest in the two complete clearance plots (37), and intermediate and most variable in the three uncleared forest plots (40–52). Cluster analysis showed that species composition was not affected by treatment, while neither treatment nor site affected the relative number of ant species in different feeding categories. Despite some local effects by dominant species, our results support the view that deforestation can reduce arthropod species richness. This study is unique in showing that reforestation methods (using a single tree species) can have a marked effect on arthropod species richness and composition. Specifically, it reveals that ant species richness can be greater in plantations established after partial manual clearance than complete clearance.

Impact of Forest Management on Insect Abundance and Damage in a Lowland Tropical Forest in Southern Cameroon

The rate of deforestation in West Africa was around 2% (12 000 km 2 ) per annum during the 1980s, and recent evidence from Cameroon suggests that the rate of deforestation there has increased during the 1990s. In contrast, only 360 km 2 of plantation forests were established annually during the mid-1980s in West African countries. Recent research in the Mbalmayo Forest Reserve in southern Cameroon has examined contrasting silvicultural techniques for regenerating degraded forest with West African tree species such as Terminalia ivorensis. These techniques included complete clearance, where all existing trees were felled and these and all other vegetation removed from the plots; and partial clearance methods (partial manual clearance, partial mechanical clearance and line planting), where tree-felling resulted in a reduction of 50% of the canopy cover. This paper describes a study of the impact of these techniques on arthropod abundance and the damage caused to T. ivorensis by insect pests within the Mbalmayo Forest Reserve. The amount of damage caused by leaf-mining insects, the abundance of gall-forming mites, and the number of trees affected by shoot borers were not affected by silvicultural practice. The amount of damage caused by leaf-chewing insects was greater in the line planting plots than the complete clearance plots, but the leaf area removed by insects rarely exceeded 6%. It is concluded that the degree of forest clearance before establishing plantations of T. ivorensis. does not markedly affect the amount of damage caused by arthropod pests at the spatial scale at which this study was carried out. Arthropod abundance was assessed by insecticide knockdown fogging in two study sites within the Mbalmayo Forest Reserve. A mean total of 196 arthropods m -2 was recorded, ants being the most common arthropod group (63%), followed by adult Diptera (10%) and then Hymenoptera other than ants (4%), Homoptera (4%), Thysanoptera (4%), adult Coleoptera (3%) and other groups (13%). Ants, Diptera, Araneae, Thysanoptera, Homoptera, Coleoptera and Orthoptera were significantly more abundant in the partial manual clearance plot than the complete clearance plot in one or both of the study sites. Because several of these groups are composed mainly of predatory and parasitic species, it is possible that, despite the pest damage results summarized above, the long-term likelihood of pest outbreaks occurring on T. ivorensis is lower in partial clearance than complete clearance plantations. However, our current lack of knowledge of the species composition of different arthropod groups limits the relevance of these findings.

Surface passivation by human albumin of plasmaperesis circuits reduces platelet accumulation and thrombus formation. Experimental and clinical studies

The contact of flowing blood with an artificial surface leads to adsorption of plasma proteins, followed by platelet adhesion and aggregation and thrombus formation. This phenomenon is enhanced by turbulent flow at joints, bifurcations, and constrictions. In therapeutic plasmapheresis using an IBM blood cell separator, blockage of the extracorporeal circulation system by platelet-fibrin thrombi imposed a halt in treatment for manual clearance of the circuit for 66 in 149 cases (44%). Thus it was decided to passivate the surface of the extracorporeal circuit by filling the tubing with 4% human serum albumin 15-20 min before the treatment session and then displacing the albumin solution with the patient's blood without creating an air-liquid interface. After introduction of this technique, a blockage was observed for only 11 in 239 cases (5%). In vitro measurements of platelet accumulation on the internal surface of the circulation system were carried out using washed human platelets labeled with 111In-oxine in the presence of a 40% hematocrit. Preadsorption of the surface with albumin reduced platelet deposition to 4-5% that observed for an equivalent pretreatment with physiological saline.

Observations on control ofPistia stratiotes linn. In fish ponds by “Gramoxone”

An account is given of the yard and field trials conducted at Cuttack which showed that ‘Gramoxone’ (20% paraquat) at 0·1 to 0·2 kg/ha. (a.i.) gave complete control ofPistia stratiotes in one to two weeks’ time. The cost of clearance by the weedicide worked out to Rs. 64–93/ha as against Rs. 168–178/ha. for manual clearance. Treatment in instalments is recommended to avoid oxygen depletion due to rotting of treated weed mass and consequent fish mortality.