References of "Environmental Monitoring & Assessment"
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See detailGame over! Wildlife collapse in northern Central African Republic
Bouché, Philippe ULg; Nzapa Mbeti Mange, Roland; Tankalet, Floride et al

in Environmental Monitoring & Assessment (2012), 184(11), 7001-7011

The wildlife populations of northern Central African Republic (CAR) have long suffered intense uncontrolled hunting. Socio-political turmoil in northern CAR that started in 2002 resulted in a rebellion in ... [more ▼]

The wildlife populations of northern Central African Republic (CAR) have long suffered intense uncontrolled hunting. Socio-political turmoil in northern CAR that started in 2002 resulted in a rebellion in 2006. An aerial sample count was carried out in northern CAR after the cease-fire to assess the impact of this troubled period on wildlife. The survey was flown at the end of the dry season in February-March 2010. It covered a landscape complex of 95 000 km² comprising national parks, hunting reserves and community hunting areas. Comparison with earlier surveys reveal a dramatic decline of wildlife: the numbers of large mammals fell by 94% in 30 years, probably due to poaching, loss of habitat and diseases brought by illegal movements of cattle. Elephant (Loxodonta africana), reduncini and topi (Damaliscus lunatus) populations showed the greatest decline (each over 90%). Other species declined by 70 to 80% during the same period. The future of the rest of the wildlife in this area is dark without a strong commitment to provide adequate funding and quickly implement determined field management. Reinforced cooperation with neighbouring Chad and Sudan is required since they are facing similar problems. [less ▲]

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See detailA Regional Inventory and Monitoring Setup to Evaluate Bark Peeling Damage by Red Deer (Cervus Elaphus) in Coniferous Plantations in Southern Belgium
Gheysen, Thibaut; Brostaux, Yves ULg; Hebert, Jacques ULg et al

in Environmental Monitoring & Assessment (2011), 181(1-4), 335-45

Bark peeling by red deer (Cervus elaphus L.) has become a serious issue for productive forests in western Europe. The damage is particularly severe on species such as spruce, as these become vulnerable to ... [more ▼]

Bark peeling by red deer (Cervus elaphus L.) has become a serious issue for productive forests in western Europe. The damage is particularly severe on species such as spruce, as these become vulnerable to fungus attacks that result in considerably depreciated timber. This article presents a monitoring setup for recent bark peeling damage in spruce plantings in Wallonia (southern part of Belgium). This setup implies to collect data annually from a survey involving cluster sampling. It has been employed since 2004 in coniferous stands amounting to 165,000 ha of land, where Norway spruce is the predominant species. The study area was divided into blocks delineated along features preventing deer migrations. A set of indicators was computed either at the whole study area level or at block level. The resulting set of indicators enabled forest managers to follow up debarking intensity in productive forests. Additional analyses were carried out in order to assess the relationship between the social position of trees in the stand and the debarking probability on the one hand, and the relationship between the variation in damage magnitude and seasonality, namely summer versus winter, on the other hand. [less ▲]

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See detailReview of indicators and field methods for monitoring biodiversity within national forest inventories. Core variable : Deadwood
Rondeux, Jacques ULg; Sanchez, Christine

in Environmental Monitoring & Assessment (2009)

Deadwood is one of the four elements taken into account in this review of indicators and field methods and is often considered as a key indicator of forest biodiversity. We have analysed the main types of ... [more ▼]

Deadwood is one of the four elements taken into account in this review of indicators and field methods and is often considered as a key indicator of forest biodiversity. We have analysed the main types of surveys and have realised how greatly the needs and constraints used to monitor deadwood can vary among them. For instance, classical National Forest Inventories usually tend to avoid time-consuming collecting methods. In the wide variety of existing definitions of deadwood, such inventories require simple and clear definitions, especially in terms of quantified thresholds. Thus, deadwood is properly described by characterising several components, such as snags, logs, stumps, branches and fine woody debris. Deadwood sampling methods alter depending on the different components and dimensions considered (standing dead trees, lying dead trees and branches, etc. assessed quantitatively). Attributes such as tree species and stage of decay are used mainly to qualify the deadwood components. The deadwood volume estimations are usually based on classical approaches already applied to living or felled trees: volume equations and/or formulas giving the volumes of common geometric solids. The purpose of this paper is to focus on different deadwood assessment techniques and to provide the information necessary to identify the most relevant methods for collecting deadwood data. The latter is used to build indicators that characterise the evolution of forest biodiversity at the scale of large forest territories. [less ▲]

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See detailDesign of a watercourse and riparian strip monitoring system for environmental management
Debruxelles, N.; Claessens, Hugues ULg; Lejeune, Philippe ULg et al

in Environmental Monitoring & Assessment (2009), 156

Watercourses are complex ecosystems where numerous economic, ecological and heritage issues converge. To ensure their efficient management it is essential to have a full description of these ... [more ▼]

Watercourses are complex ecosystems where numerous economic, ecological and heritage issues converge. To ensure their efficient management it is essential to have a full description of these multifunctional ecosystems and to know their evolution over time. This paper describes a method for monitoring watercourses and their riparian strips developed in Wallonia (southern Belgium). It is based on an inventory constructed by stratified random sampling comprising 1,071 sampling plots distributed over a total length of 24,600 km of watercourses covered from their source. Each sampling plot is surveyed and measurements and fine observations are made on watercourse segments 50 m long. The method developed, which was applied on a regional scale, could easily be transposed to other entities, from large river basins, to an entire country. Examples of results obtained from a first inventory phase demonstrate the utility of this tool designed to supply qualitative and quantitative information to assist watercourse management. [less ▲]

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See detailMonitoring of the atmospheric burdens of CH4, N2O, CO, CHCIF2 and CF2Cl2 above Central Europe during the last decade
Zander, Rodolphe ULg; Demoulin, Philippe ULg; Mahieu, Emmanuel ULg

in Environmental Monitoring & Assessment (1994, May), 31(1-2), 203-209

Based on high spectral resolution infrared solar observations made at the International Scientific Station of the Jungfraujoch, Switzerland, total vertical column abundances of 18 atmospheric gases have ... [more ▼]

Based on high spectral resolution infrared solar observations made at the International Scientific Station of the Jungfraujoch, Switzerland, total vertical column abundances of 18 atmospheric gases have been monitored routinely since 1984. The observed temporal evolutions in the columns of CH4, N2O, CO, CHClF2 (HCFC-22) and CF2Cl2 (CFC-12) are reported here as typical examples of this monitoring effort which is conducted within the frame of ''Global Change'' and ''Network for the Detection of Stratospheric Change'' programs. [less ▲]

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