Sustainable forest management practice in Central African States and customary law

Sustainable forest management (SFM) has become a major focus for the international community. This is because of the multifunctional importance of forest resources for the entire planet, namely ecological, socio-economic, cultural and climatic balance. General awareness of forest importance unfortunately coincides with the observed increase in threats, especially anthropogenic, to this world heritage. To tackle the continuing deforestation and degradation, the international community, through the United Nations Forum on Forests (UNFF) and its predecessors, has attempted to adopt an international convention on SFM based on the 15 Rio Declaration principles. The limited success of international negotiations aimed at the adoption of such an instrument leads us to seek an alternative within international law theories, through analysis of the relationship between states practice in SFM and customary international law. To this end, this paper focuses on the practice of Central African States in sustainable forest management, especially statement of principles, sub-regional treaty and domestic legislation. The analysis shows that their practice fulfils all the requirements in order to be regarded as regional custom. Therefore, principles and state practices of SFM can thus be considered legally binding for this sub-region, despite some major implementation shortcomings.     

Land-cover changes in an urban lake watershed in a mega-city, Central China

Urbanization can exert a profound influence on land covers and landscape characteristics. In this study, we characterize the impact of urbanization on land cover and lacustrine landscape and their consequences in a large urban lake watershed, Donghu Lake watershed (the largest urban lake in China), Central China, by using Landsat TM satellite images of three periods of 1987, 1993 and 1999 and ground-based information. We grouped the land covers into six categories: water body, vegetable land, forested land, shrub-grass land, open area and urban land, and calculated patch-related landscape indices to analyze the effects of urbanization on landscape features. We overlaid the land cover maps of the three periods to track the land cover change processes. The results indicated that urban land continuously expanded from 9.1% of the total watershed area in 1987, to 19.4% in 1993, and to 29.6% in 1999. The vegetable land increased from 7.0% in 1987, 11.9% in 1993, to 13.9% in 1999 to sustain the demands of vegetable for increased urban population. Concurrently, continuous reduction of other land cover types occurred between 1987 and 1999: water body decreased from 30.4% to 23.8%, and forested land from 33.6% to 24.3%. We found that the expansion of urban land has at least in part caused a decrease in relatively wild habitats, such as urban forest and lake water area. These alterations had resulted in significant negative environmental consequences, including decline of lakes, deterioration of water and air quality, and loss of biodiversity.     

近50年华中地区霾污染的特征

基于1962~2011年霾日观测资料,使用线性回归、聚类分析及相关分析等统计方法分析了近50年华中地区霾污染的时空变化特征及其成因.结果表明,华中地区的霾高发中心位于河南中北部、湖北中西部和湖南中部人口集中的气溶胶浓度高值区,其中霾日数最多的站点为河南新乡,年均达到79.1d.霾的季节性变化表现为冬季霾日数最多,夏季最少,霾污染是典型的冬季大气环境事件.但随着近年春夏秋三季霾日的增加,华中地区霾污染的季节性差异减小.城市地区是华中霾污染严重的区域.近50年污染地区霾发生频率增多,而相对清洁地区霾污染发生频率减少.华中地区大气环境呈现出两极分化的变化特征.近50年来华中地区霾日增加受人为污染物排放加强和东亚季风减弱的共同影响.     

Fine root decomposition and nutrient release in Toona sinensis plantation under the reconstruction mode of low-efficiency cypress forest gaps北大核心CSCD

Fine root decomposition is an important way in which nutrients are returned to plantation soil; thus, further study of this process will be helpful for understanding material cycling in forest ecosystems. We investigated a Toona sinensis plantation in the central Sichuan hilly region using litter bags containing T. sinensis fine roots to evaluate the dynamics of fine root decomposition and nutrient release for one year in forest gaps of 50 m2 (L1), 100 m2 (L2), and 150 m2 (L3). The results showed that T. sinensis fine root decomposition was fastest in the first 90 days. As time passed, the decomposition rate slowed. One year later, the residue rate was 75.44%, 73.92%, and 72.07%, respectively. The fine root decomposition rate of L3 was greater than that of L2, which was greater than that of L1. During fine root decomposition, the dynamics of the fine root nutrient concentrations changed. C, P, and K concentrations of the fine roots declined in forest gaps, while N, Ca, and Mg concentrations increased overall in the fine roots. In conclusion, forest gaps had effects on the fine root decomposition and nutrient release of T. sinensis, and different sized forest gaps produced different results. © 2018 Science Press. All rights reserved.     

The livestock production system in a village ecosystem in the Rawain Valley,Uttarakhand, Central Himalaya

Animals in the Himalayan region are reared basically to supplement the family income and sustain crop production, and constitute an important component of the rural economy of the region. Given the ecological importance of the livestock production system in terms of intrinsic values as a life support system for local people and a contribution towards sustainable agriculture through its role in the maintenance of soil fertility, the present study was conducted. This paper describes and assesses the current status of livestock production systems, monetary input/output, status of available forest resources, current level of pressure on the livestock production system and recommends strategies for sustainable development of a livestock production system in the Rawain Valley of Central Himalaya.     

The imperiled fish fauna in the Nicaragua Canal zone

Large‐scale infrastructure projects commonly have large effects on the environment. The planned construction of the Nicaragua Canal will irreversibly alter the aquatic environment of Nicaragua in many ways. Two distinct drainage basins (San Juan and Punta Gorda) will be connected and numerous ecosystems will be altered. Considering the project's far‐reaching environmental effects, too few studies on biodiversity have been performed to date. This limits provision of robust environmental impact assessments. We explored the geographic distribution of taxonomic and genetic diversity of freshwater fish species (Poecilia spp., Amatitlania siquia, Hypsophrys nematopus, Brycon guatemalensis, and Roeboides bouchellei) across the Nicaragua Canal zone. We collected population samples in affected areas (San Juan, Punta Gorda, and Escondido drainage basins), investigated species composition of 2 drainage basins and performed genetic analyses (genetic diversity, analysis of molecular variance) based on mitochondrial cytb. Freshwater fish faunas differed substantially between drainage basins (Jaccard similarity = 0.33). Most populations from distinct drainage basins were genetically differentiated. Removing the geographic barrier between these basins will promote biotic homogenization and the loss of unique genetic diversity. We found species in areas where they were not known to exist, including an undescribed, highly distinct clade of live bearing fish (Poecilia). Our results indicate that the Nicaragua Canal likely will have strong impacts on Nicaragua's freshwater biodiversity. However, knowledge about the extent of these impacts is lacking, which highlights the need for more thorough investigations before the environment is altered irreversibly.     

A survey of lead pollution in Chhattisgarh State, central India

Lead (Pb) is of major environmental concern due to its toxicological importance. The anthropogenic emission of Pb is at least 100 times higher than natural emissions. Soil and dust are significant sources of Pb exposure. Lead is generally immobile in soil and accumulates in the upper layers. Lead particles may enter homes via shoes, clothes, pets, and windows. Central India is rich in deposits of natural resource materials such as coal, pyrite, dolomite, and alumina that contain Pb and other heavy metals at the trace levels, and the substantial exploitation of these materials has tended to increased contamination of water and geological formations. Here we present data on Pb concentrations in the water, soil and sediment samples (n=158) collected from 70 locations in Chhattisgarh state, Raipur region. Lead concentrations in the surface water (n=44), groundwater (n=44), soils (n=60) and sediments (n=10) ranged from 6 to 1410, 3 to 52, 12.8 to 545, and 31 to 423 μg g⁻¹, with mean values of 305, 16, 102 and 190 μg g⁻¹, respectively. Most of the Pb fractions of >80% can be leached out with the chemical extractants EDTA, acetic acid, and hydroxylamine hydrochloride. Lead has accumulated in the soil clay fraction due to its relatively large surface area and decreases with increasing depth in the soil profile.     

Comments on “turbulent velocity profile in fully-developed open channel flows”

In a recent paper published in this journal, Bonakdari et al. (Environ Fluid Mech 8:1–17, 2008) presented a new formulation of the vertical velocity profile in the central portion of steady fully developed turbulent open-channel flows which is based on an analysis of the Navier–Stokes equations. The predicted mean streamwise velocity profiles presented by the authors represent dip phenomenon (maximum velocity below the free surface). The discusser would like to point out some contradictions and an error in the main demonstration. This error appears in the right-hand side term of the main Eq. 22 (Environ Fluid Mech 8:1–17, 2008) in the parameter α. Our corrected demonstration shows that α is equal to and not to as obtained by the authors (Environ Fluid Mech 8:1–17, 2008). The values of α used by the authors are under-estimated by 1, this difference has a significant effect on velocities and therefore will involve a difference between measured and predicted velocity profiles. Finally, the assumption of at the free surface is in contradiction with predicted velocity profiles.     

Fetal curarization for prenatal magnetic resonance imaging

Fetal magnetic resonance (MR) imaging was performed at 33 weeks of gestation for investigation of a posterior fossa abnormality found at ultrasound screening. Fetal movements were abolished by vecuronium injected under ultrasound guidance into the umbilical vein. MR images showed atrophy of the left cerebellar lobe with cisternal dilatation. These were confirmed postnatally by CT scan.