The expected impact of the “Peace Conduit” project (the Red Sea - Dead Sea pipeline) on the Dead Sea

The Dead Sea is a severely disturbed ecosystem, greatly damaged by anthropogenic intervention in its water balance. During the 20th century, the Dead Sea level dropped by more than 25 meters, and presently (2003) it is at about 416 meters below mean sea level. This negative water balance is mainly due to the diversion of water from the catchment area of the lake by Israel, Jordan and Syria. During the 2002 World Summit on Sustainable Development Israel and Jordan jointly announced their interest in saving the Dead Sea by constructing the “Peace Conduit” that will pipe water from the Red Sea to the Dead Sea. The inflow of seawater (or reject brine after desalinization) into the Dead Sea will have a major impact on its limnology, geochemistry and biology. During the filling stage, relatively diluted surface water will form and the rate of evaporation will therefore increase. Dilution of the surface water will most likely result in microbial blooming whose duration is not known, while the lower water layer is likely to develop reducing conditions, including bacterial sulfate reduction and presence of hydrogen sulfide (H₂S). Mixing between the calcium-rich Dead Sea brine and the sulfate-rich seawater will result in gypsum precipitation (CaSO₄⋅ 2H₂O). Once the target level is reached, inflow will be outbalanced by evaporation and salinity of the surface water will increase due to accumulation of seawater-salts. The water column will re-mix when the density of the surface water will equal that of the lower water column. In spite of its large volume and high salinity relative to that of the inflowing water, over the long run the composition of this unique lake will change. Before a decision is made on the planning and construction of the Conduit, it is essential that the long term evolution and characteristics of the “renewed” Dead Sea be known and anticipated changes examined. Once decided upon, the planning and construction of the Conduit should be conducted so as to minimize possible negative impacts of seawater introduction on the Dead Sea. This can only be achieved through a thorough understanding of the expected changes in the limnological physical/chemical characteristics of the Dead Sea and its unique brine.     

The Expected Impact of the Peace Conduit Project (The Red Sea – Dead Sea Pipeline) on the Dead Sea

The Dead Sea of Israel, Jordan and Syria is a severely disturbed ecosystem, greatly damaged by anthropogenic intervention in its water balance. During the 20 th century, the Dead Sea level dropped by more than 25 meters, and presently (2003) it is at about 416 meters below mean sea level. This negative water balance is mainly due to the diversion of water from the catchment area of the lake by Israel, Jordan and Syria. During the 2002 World Summit on Sustainable Development Israel and Jordan jointly announced their interest in saving the Dead Sea by constructing the ‘Peace Conduit’ that will pipe water from the Red Sea to the Dead Sea. The inflow of seawater (or reject brine after desalinization) into the Dead Sea will have a major impact on its limnology, geochemistry and biology. During the filling stage, relatively diluted surface water will form and the rate of evaporation will therefore increase. Dilution of the surface water will most likely result in microbial blooming whose duration is not known, while the lower water layer is likely to develop reducing conditions, including bacterial sulfate reduction and presence of hydrogen sulfide (H₂S). Mixing between the calcium-rich Dead Sea brine and the sulfate-rich seawater will result in gypsum precipitation (CaSO₄·2H₂O). Once the target level is reached, inflow will be outbalanced by evaporation and salinity of the surface water will increase due to accumulation of sea water-salts. The water column will remix when the density of the surface water will equal that of the lower water column. In spite of its large volume and high salinity relative to that of the inflowing water, over the long run the composition of this unique lake will change. Before a decision is made on the planning and construction of the Conduit, it is essential that the long term evolution and characteristics of the ‘renewed’ Dead Sea be known and anticipated changes examined. Once decided upon, the planning and construction of the Conduit should be conducted so as to minimize possible negative impacts of seawater introduction on the Dead Sea. This can only be achieved through a thorough understanding of the expected changes in the limnological physical/chemical characteristics of the Dead Sea and its unique brine.     

Viable engineering options to enhance the NaCl quality from the Dead Sea in Jordan

The Dilemma of the Dead Sea is briefly addressed. The Dead Sea is a major source for the production of food grade Sodium Chloride (NaCl) through the use of traditional salt grinding, multiple washing stages and then evaporation. But there have been problems in producing industrial grade NaCl due to the high percentage of Ca⁺² and Mg⁺² ion concentrations. Pilot plant experiments were conducted to simulate a sodium chloride recovery from the Dead Sea brines. Viable engineering options were examined and tested. These options are classified either by adding certain chemicals such as the use of Sodium Stearate and Sodium Carbonate or implementing and modifying process conditions. The changes in operating conditions involve; reducing the particle size and changing both water type and contact time in the washing stages, adding a low 45 rpm agitator and finally investigating the appropriate water type scheme to be used in a double washing system. These changes have significant impact in enhancing NaCl recovery especially when brackish water is used. Also brine/brackish scheme is the best choice to be used in a double washing operation.     

近30年来高邮湖(含邵伯湖)自然水域面积变化及其影响因素

湖泊水域面积变化特征反映气候与人类活动对湖泊生态系统结构与功能的影响,对湖泊健康评价与水生态修复有重要指导价值.以1988-2015年8期Landsat TM/ETM+遥感影像为数据源,综合运用目视解译法与比值阈值法提取了研究区高邮湖（含邵伯湖）及其围网养殖区的边界信息,分析了研究区水域面积变化特征及其影响因素.结果表明:①1988-2015年研究区自然水域面积呈现前期持续缩小、近期部分恢复的阶段性变化趋势.其中,1988-2000年自然水域面积缓慢缩减,平均减小速率为4.08 km2/a;2000-2011年迅速缩减,平均减小速率为12 km2/a;2011-2015年迅速增长,自然水域面积增加108 km2;1988年自然水域面积最大（716 km2）,2011年最小（535 km2）,2015年部分恢复（643 km2）.②1988-2015年流域内年均降水量先减后增,年均气温逐渐升高.年均气温升高与自然水域面积变化具有相关性（R2=0.472）;年均降水量则与自然水域面积变化无明显关联（R2=0.118）.③1988年和1992年研究区内未见明显的围网养殖,2000年围网养殖区面积仅为45 km2,2011年最大,达199 km2.2000-2009年和2009-2015年围网养殖区面积平均增长速率分别为15.56和9.00 km2/a;北部湖区围网养殖集中,自然水域面积变化最为显著,东西湖区次之.研究显示,1988年以来,年均气温和围网养殖对高邮湖自然水域产生了显著影响,湖区北部湿地侵占严重,湿地生态屏障功能下降.      

Forest policies and programs affecting vulnerability and adaptation to climate change

Due to large scale afforestation programs and forest conservation legislations, India’s total forest area seems to have stabilized or even increased. In spite of such efforts, forest fragmentation and degradation continues, with forests being subject to increased pressure due to anthropogenic factors. Such fragmentation and degradation is leading to the forest cover to change from very dense to moderately dense and open forest and 253 km² of very dense forest has been converted to moderately dense forest, open forest, scrub and non-forest (during 2005–2007). Similarly, there has been a degradation of 4,120 km² of moderately dense forest to open forest, scrub and non-forest resulting in a net loss of 936 km² of moderately dense forest. Additionally, 4,335 km² of open forest have degraded to scrub and non-forest. Coupled with pressure due to anthropogenic factors, climate change is likely to be an added stress on forests. Forest sector programs and policies are major factors that determine the status of forests and potentially resilience to projected impacts of climate change. An attempt is made to review the forest policies and programs and their implications for the status of forests and for vulnerability of forests to projected climate change. The study concludes that forest conservation and development policies and programs need to be oriented to incorporate climate change impacts, vulnerability and adaptation.     

Vulnerability assessment and adaptation to the impacts of sea level rise on the Kingdom of Bahrain

This paper assesses quantitatively the impact of sea level rise (SLR) at the global and regional scale as a result of climate change (CC) on the coastal areas of the Kingdom of Bahrain’s islands (36 Islands). The standard Intergovernmental Panel on Climate Change (IPCC) guidelines was modified as appropriate for the situation of the study area. Geographic Information Systems (GIS) coupled with Remote Sensing (RS) were used as the main techniques of collecting, analyzing, modeling simulating and disseminating information to build SLR scenarios in a geographically referenced context. Also, these tools were used to assess vulnerability and risk of the coastal area of the islands with the expectation that coastal planner and government authorities will profit from integrating these knowledge into a broad based environmental decision making. Three SLR scenarios: low, moderate and high were developed to examine the impacts from SLR on all islands. The low SLR scenario (Optimistic) assumes a 0.5-m rise above current sea level, the moderate scenario (Intermediate) assumes a one meter rise, and the high scenario (Pessimistic) assumes a 1.5 m rise in sea level. Two more SLR scenarios were assumed to perform risk analysis, a 2 and 5 meter rise above current sea level. The simulation of SLR are quite straightforward, emphasizing on the uses of both of the data that are incorporated from the satellite images and the created Digital Elevation Model (DEM) to estimate SLR scenarios that are adapted in the study. These data were used to predict consequences of the possibility of the rise in sea level at different scenarios which may alter the landuse and patterns of human communities. Results indicate that low-lying coastal areas of Bahrain islands are at risk from the effects of any SLR resulting from CC. These islands are vulnerable under different SLR Scenarios. More than 17% of the country total area may be inundated under 1.5 m SLR in 2100. The total area that might be lost under different sea level scenarios will vary from more than 77 km² if SLR reaches 0.5 m, to about 100 km² under 1.0 m SLR and may reach 124 km² under 1.5 m SLR scenario. The total inundated areas due to risk scenarios will reach 133 km², if the SLR rises to 2.0 m, and it is estimated to be more than (22%) of the main island total area. Under the second scenario, if the SLR reaches 5.0 m, the main islands will lose approximately half of its area (47%) equal to 280 km². Hawar islands group will lose about (30%) of its total area under 2.0 m SLR, which is about 15.5 km².A SLR adaptation policy framework (APF) and adaptation policy initiatives (APIs) are suggested for planners to build upon for reducing the likely effects of SLR in the Kingdom of Bahrain. The framework is composed of four steps namely, acquisition of information, planning and design, implementation and monitoring and evaluation. A general policy framework for a national response to SLR is suggested. Additionally, a range of policy adaptation options/initiatives to sustain coastal developments under the likely effects of SLR are recommended.     

Human Settlements on the Northern Shores of Lake Aral and Water Level Changes

The shore of Lake Aral in Kazakhstan is a perfect area for studying the human adaptation strategy to past climate changes. New archaeological material, gathered along the northern shores during the expedition of the INTAS project CLIMAN, is briefly presented. Changes in settlement activity during the Atlantic and Subboreal are related to lake level changes of the Aral Sea. A previ-ously proposed lake level maximum needs to be revised. In particular the lake level stand at 72/73 m, with an assumed age of 5000 BP is definitely refused. Based on the presented data the maximum lake level most probably never reached beyond 57/58 mean average sea level (masl). Furthermore the regression during the 15^th–16^th centuries has been underestimated. It may have been lower than the present day level. Thus the present desiccation of the Aral Sea is historically not unique, as a similar regression, probably induced by man as well, has occurred at least once during history. A readjustment of the water level is, therefore, possible at any time.     

A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort

Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species–people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km²) and provinces (2,900 km²). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population–biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.     

Black Sea beaches vulnerability to sea level rise

Integrated Coastal Zone Management (ICZM) aims to promote sustainable management of coastal zones based on ecosystem and holistic management approaches. In this context, policies have to consider the complex interactions that influence the fragile equilibrium of coastal ecosystems. Beaches represent both valuable and vulnerable natural resources because of the various ecosystem services they provide and their sensitivity to climate change and sea level rise.We present the first comprehensive digital record of all Black Sea beaches and provide a rapid assessment of their erosion risk under different scenarios of sea level rise. Through the digitisation of freely available remote-sensed images on the web, we provide broad information on the spatial characteristics and other attributes of all Black Sea beaches (e.g. photo-based visual estimation of the sediment type, presence of coastal defences, urban development). These data have been assembled and stored in full Spatial Data Infrastructure (SDI) – allowing spatial queries, visualisation and data sharing – and are therefore particularly interesting to feed/supply web-GIS portals (coastal atlases) for visualisation purpose, spatial queries or spatial indicators calculations.The resulting Black Sea beaches database contains 1228 beaches, with a total coastline length of 2042 km with an area of 224 km². The majority of the Black Sea beaches have been found to have small widths (61% have maximum widths less than 50 m), whereas 47% of all beaches presented coastal defence schemes, suggesting an already serious beach erosion problem.The erosion risk of the Black Sea beaches was assessed through the comparison of their maximum widths with estimations of the sea level rise-induced retreat by an ensemble of six 1-D analytical and numerical morphodynamic models. Following more than 17,000 experiments using different combinations of wave conditions, beach sediment textures and slopes and 11 scenarios of sea level rise (up to 2 m), the means (best fits) of the lowest and highest projections by the model ensemble were estimated; these were then compared to the maximum widths of the Black Sea beaches. The analysis showed that sea level rise will have highly significant impacts on the Black Sea beaches, as for a 0.5 m sea level rise 56% of all beaches are projected to retreat by 50% of their maximum width. For a 0.82 m sea level rise (the high IPCC estimate for the period 2081–2100) about 41% are projected to retreat by their entire maximum width, whereas for 1 m sea level rise about 51% of all Black Sea beaches are projected to retreat by (drowned or shifted landward by) their entire maximum width, if the high mean of the model ensemble projections is used.Results substantiate the risk of beach erosion as a major environmental problem along the Black Sea coast, which therefore needs to be taken into account in any future coastal management plans, as a matter of urgency. As these scenarios consider only sea level rise, they are considered to be conservative. Although the present results cannot replace detailed studies, the database and projections may assist Black Sea coastal managers and policy makers to rapidly identify beaches with increased risk of erosion, valuate accordingly coastal assets and infrastructure, estimate beach capacity for touristic development purposes, and rapidly assess direct and indirect costs and benefits of beach protection options. They also provide the necessary inputs to advance discussions relevant to the Black Sea ICZM.     

开都河灌区灌溉引水对博斯腾湖面积影响的定量分析

开都河是注入博斯腾湖的最大河流,1958～2002年间平均入湖水量达23.62×10⁸m³,占博斯腾湖总补给量的80%以上。1958年以来开都河灌区灌溉引水量维持在8.17×10⁸m³～13.18×10⁸m³之间,其中20世纪60年代灌溉引水量平均为10.14×10⁸m³/a,占开都河径流量的31.1%;70年代引水量上升到12.15×10⁸m³/a,为开都河径流量的36.5%;80年代引水量下降到11.29×10⁸m³/a,但引水量仍占开都河径流量的36.5%;90年代灌溉引水量进一步降至9.85×10⁸m³/a,仅占径流量的27.1%。通过水量平衡分析和相关回归计算,得出开都河灌区灌溉引水对博斯腾湖面积影响的数值:20世纪60年代平均值为62.4km²;70年代平均值为80.8km²;80年代、90年代分别为90.4km²、76.7km²,2000年以来平均仅为41.3km²。由此可见,45年来开都河灌区灌溉引水对博斯腾湖面积的影响经历了弱→强→弱的变化过程。     

Headwater streams: neglected ecosystems in the EU Water Framework Directive. Implications for nitrogen pollution control

The European Union Water Framework Directive (WFD) aims to achieve the “good status” of waters by 2015, through monitoring and control of human impacts on “bodies of surface water” (BSWs), discrete elements for quality diagnosis and management. Headwater streams, however, are frequently neglected as they are not usually recognised as BSW. This poses limitations for the management of river catchments, because anthropogenic impacts on headwaters can constrain the quality of downstream rivers. To illustrate this problem, we compared nitrate levels and land use pressures in a small agricultural catchment with those recorded in the catchment in which it is embedded (Ega), and in the Ebro River Basin (NE Spain) comprising both. Agriculture greatly influenced water nitrate concentration, regardless of the size of the catchments: R² = 0.91 for headwater catchments (0.1–7.3 km²), and R² = 0.82 for Ebro tributary catchments (223–3113 km²). Moreover, nitrate concentration in the outlet of a non-BSW small river catchment was similar to that of the greater downstream BSW rivers. These results are of interest since, despite representing 76% of the length of the Ega catchment hydrographical network, only 3.1% of the length of the headwater streams has been identified as BSWs. Human activities affecting headwater streams should therefore be considered if the 2015 objective of the WFD is to be achieved.     

Climate change and sandy land development in Qinghai Lake Watershed, China

The Qinghai Lake Watershed, containing the largest saline lake in northwest of China, has suffered from severe sandy land development in recent years. This paper analyzes its daily precipitation, temperature, and wind from 1958 to 2001, and the spatial and temporal distributions of sandy land through the interpretation of remote sensing images covering four years (1977, 1987, 2000, and 2004). Results showed that since the middle of the 1960s, the daily precipitation (P) of 0<P⩽5 mm decreased, while the P>20 mm increased significantly (S<0.05) in their annual total amounts and days. The maximum daily precipitation also increased significantly. Both the maximum dry spell and the total dry spell of more than ten days had a significant upward trend. Since the beginning of the 1960s, all the extremely high, extremely low and mean temperatures increased significantly (S<0.01), at a rate of 0.1°C/10a, 0.2°C/10a, and 0.2°C/10a, respectively. The days with extremely high temperature had a significant upward trend, while the days with extremely low temperature had a significant downward trend. The Qinghai Lake was significantly shrinking (S<0.01) and provided abundant sediments for Aeolian erosion. The NNW wind prevailed in the watershed, and the largest scale wind was from the west and concentrated on the dry months. As a result, the sandy land was mainly born on the east bank of Qinghai Lake. The total sandy land area in the watershed had grown from 587.4 km², 660.7 km², 697.6 km² to 805.8 km², accordingly, its area percentage growing from 2.0%, 2.2%, 2.4% to 2.7%, respectively.     

江汉湖群围垦变化的遥感测定

为了监测江汉湖群的湖泊资源,研究湖泊围垦变化对湖区环境生态的影响,本试验利用陆地卫星遥感图象的光学仿射纠正技术和机助扫描统计方法,对湖北省湖泊的个数和面积进行了统计,并将八十年代初与五十年代末统计数据作了比较分析。发现江汉湖群的湖泊个数由五十年代末的609个减少到现在的309个,湖泊常年水位面积由4708km~2缩减到2657km~2.七十年代以来的过度围垦,使湖区生态平衡遭到严重破坏,调蓄、水产和水资源受到损失、研究表明.监测江汉湖群的动态演变,进行合理的湖区开发,加强湖泊的科学管理,已到非重视不可的时候了.     

Linking spatio-temporal variation of crop response with sediment deposition along paddy rice terraces

In tropical mountainous regions of South East Asia, intensive cultivation of annual crops on steep slopes makes the area prone to erosion resulting in decreasing soil fertility. Sediment deposition in the valleys, however, can enhance soil fertility, depending on the quality of the sediments, and influence crop productivity. The aim of the study was to assess (i) the spatio-temporal variation in grain yield along two rice terrace cascades in the uplands of northern Viet Nam, (ii) possible linkage of sediment deposition with the observed variation in grain yield, and (iii) whether spatial variation in soil water or nitrogen availability influenced the obtained yields masking the effect of inherent soil fertility using carbon isotope (¹³C) discrimination and ¹⁵N natural abundance techniques. In order to evaluate the impact of seasonal conditions, fertilizer use and sediment quality on rice performance, ¹⁵N and ¹³C stable isotope compositions of rice leaves and grains taken after harvest were examined and combined with soil fertility information and rice performance using multivariate statistics. The observed grain yields for the non-fertilized fields, averaged over both cascades, accounted for 4.0 ± 1.4 Mg ha^?1 and 6.6 ± 2.5 Mg ha^?1 in the spring and summer crop, respectively, while for the fertilized fields, grain yields of 6.5 ± 2.1 Mg ha^?1 and 6.9 ± 2.1 Mg ha^?1 were obtained. In general, the spatial variation of rice grain yield was strongly and significantly linked to sediment induced soil fertility and textural changes, such as soil organic carbon (r 0.34/0.77 for Cascades 1 and 2, respectively) and sand fraction (r ?0.88/?0.34). However, the observed seasonal alteration in topsoil quality, due to sediment deposition over two cropping cycles, was not sufficient to fully account for spatial variability in rice productivity. Spatial variability in soil water availability, assessed through ¹³C discrimination, was mainly present in the spring crop and was linearly related to the distance from the irrigation channel, and overshadowed in Cascade 2 the expected yield trends based on sediment deposition. Although δ¹⁵N signatures in plants indicated sufficient N uptake, grain yields were not found to be always significantly influenced by fertilizer application. These results showed the importance of integrating sediment enrichment in paddy fields within soil fertility analysis. Furthermore, where the effect of inherent soil fertility on rice productivity is masked by soil water or nitrogen availability, the use of ¹³C and ¹⁵N stable isotopes and its integration with conventional techniques showed potential to enhance the understanding of the influence of erosion – sedimentation and nutrient fluxes on crop productivity, at toposequence level.     

Sediment and nutrient dynamics during snowmelt runoff generation in a southern Taiga catchment of Russia

The water quality of the Volga catchment, Russia, is diminished and major nutrients reach critical levels. Proper management strategies depend on process knowledge about nutrient sources and pathways as well as appropriate models. For the 18.8 km² experimental catchment Lubazhinkha, 100 km south of Moscow, a monitoring scheme was conducted to identify runoff generation and nutrient source areas. The grey forest soils of the catchment are utilized with arable land and pasture (54%) and forest areas. The received results show a high intra-annual and inter-annual dynamic of the snowmelt runoff generation as major hydrological process. Overall sediment export rates during the 3 years of snowmelt investigation from 2003 to 2005 are low with a maximum of 0.33 t ha⁻¹ during snowmelt period 2005 and effectively reduced by a dam at the catchment outlet. Also, the total phosphorus loss from the catchment is low reaching from 0.03 to 0.35 kg ha⁻¹ during the snowmelt periods. However, sediment and total phosphorus concentrations vary within one snowmelt event and can reach high concentrations. Detailed analysis of element concentrations during snowmelt events allows an identification of different flow components and runoff generating mechanisms. During low flow situations phosphorus and dissolved organic carbon are transferred from the arable soils with slow flow components to the channel. In contrast to this situation, the sources of sediment and nutrients split up temporarily and spatially during high flow situations. Aside arable fields that are source of sediment and phosphorus during snowmelt episodes, the forested areas were detected as major source for the export of dissolved organic carbon with surface runoff. In particular these areas are characterized by a late thawing of the topsoil which causes a delayed peak of dissolved organic carbon concentration. The awareness of the dynamic and complex catchment reaction during snowmelt events is of importance for the development of proper management strategies.     

在用汽油和柴油车排放颗粒物的粒径分布特征实测

分别选取国3～国5轻型汽油车9辆和重型柴油车15辆采用实验室底盘测功机和全流稀释定容采样系统(CVS)开展了汽柴油车尾气颗粒物排放因子实测和粒径分布比较,分析并比较了行驶工况和排放控制水平对汽柴油车尾气颗粒物排放因子和粒径分布的影响.结果表明,轻型汽油车和重型柴油车的颗粒数量单位燃料平均排放因子分别为(4.1±4.0)×10¹⁴ kg^-1和(5.7±4.3)×10¹⁵ kg^-1,重型柴油车颗粒数量排放因子是轻型汽油车的(14±7)倍.轻型汽油车超高速工况下颗粒物数量排放因子显著高于其他工况,颗粒数排放因子达到(5.1±5.0)×10¹³ km^-1,分别是低速、中速和中速工况的11.7、 14.1和7.3倍,重型柴油车高速工况颗粒数排放因子分别是低速和中速工况的2.5倍和1.4倍,且增长的颗粒物主要为核模态颗粒.国3～国5排放控制水平下汽油车颗粒物数量排放因子分别为(2.7±1.7)×10¹³、(2.6±1.3)×10¹³     

Optimizing carbon sequestration in commercial forests by integrating carbon management objectives in wood supply modeling

This paper provides a methodology for generating forest management plans, which explicitly maximize carbon (C) sequestration at the forest-landscape level. This paper takes advantage of concepts first presented in a paper by Meng et al. (2003; Mitigation Adaptation Strategies Global Change 8:371–403) by integrating C-sequestration objective functions in existing wood supply models. Carbon-stock calculations performed in Woodstock^TM (RemSoft Inc.) are based on C yields generated from volume table data obtained from local Forest Development Survey plots and a series of wood volume-to-C content conversion factors specified in von Mirbach (2000). The approach is used to investigate the impact of three demonstration forest-management scenarios on the C budget in a 110,000 ha forest in south-central New Brunswick, Canada. Explicit demonstration scenarios addressed include (1) maximizing timber extraction either by clearcut or selection harvesting for greatest revenue generation, (2) maximizing total C storage in the forest landscape and in wood products generated from harvesting, and (3) maximizing C storage together with revenue generation. The level of clearcut harvesting was greatest for scenario 1 (≥15 × 10⁴ m³ of wood and ≥943 ha of land per harvesting period), and least for scenario 2 (=0 m³ per harvesting period) where selection harvesting dominated. Because softwood saw logs were worth more than pulpwood ($60 m⁻³ vs. $40 m⁻³) and were strategic to the long-term storage of C, the production of softwood saw logs exceeded the production of pulpwood in all scenarios. Selection harvesting was generally the preferred harvesting method across scenarios. Only in scenario 1 did levels of clearcut harvesting occasionally exceed those of selection harvesting, mainly in the removal of old, dilapidated stands early in the simulation (i.e., during periods 1 through 3). Scenario 2 provided the greatest total C-storage increase over 80 years (i.e., 14 × 10⁶ Mg C, or roughly 264 Mg ha⁻¹) at a cost of $111 per Mg C due to lost revenues. Scenarios 3 and 1 produced reduced storage rates of roughly 9 × 10⁶ Mg C and 3 × 10⁶ Mg C, respectively; about 64% and 22% of the total, 80-year C storage calculated in scenario 2. The bulk of the C in scenario 2 was stored in the forest, amounting to about 76% of the total C sequestered.     

密云水库上游石匣小流域水土流失综合治理措施研究

坡面处理措施及土地利用方式是控制水土流失最重要的影响因素,通过合适的坡面措施与合理的土地利用方式可以有效地抑制土壤侵蚀,保护土地资源,改善生态坏境。论文通过对石匣小流域不同处理的径流试验小区的实测资料分析,研究了坡面综合水土保持措施对水土流失的影响。研究表明,与坡耕地、开荒地相比,梯田和水平条可以有效地拦蓄地面径流,控制水土流失,减沙率可达64.83%~91.81%,并且阴坡上的水平条的蓄水保土作用好于阳坡,有土埂的大水平条的减水拦沙效率好于无土埂的水平条;综合水保措施的水土保持效益更高,对径流量的拦蓄率高达96.21%~99.38%,并且进行综合措施处理的坡面的土壤侵蚀模数都小于水利部发布的北方土石山区允许土壤流失量200t/km².a;对坡面的自然封禁能够有效地控制坡面水土流失;同时由于综合水保措施很大程度上改变了原有的地形,坡度对水土流失的影响不明显。     

High-field 1H T1 and T2 NMR relaxation time measurements of H2O in homeopathic preparations of quartz, sulfur, and copper sulfate

Quantitative meta-analyses of randomized clinical trials investigating the specific therapeutic efficacy of homeopathic remedies yielded statistically significant differences compared to placebo. Since the remedies used contained mostly only very low concentrations of pharmacologically active compounds, these effects cannot be accounted for within the framework of current pharmacology. Theories to explain clinical effects of homeopathic remedies are partially based upon changes in diluent structure. To investigate the latter, we measured for the first time high-field (600/500 MHz) ¹H T₁ and T₂ nuclear magnetic resonance relaxation times of H₂O in homeopathic preparations with concurrent contamination control by inductively coupled plasma mass spectrometry (ICP-MS). Homeopathic preparations of quartz (10c–30c, n = 21, corresponding to iterative dilutions of 100⁻¹⁰–100⁻³⁰), sulfur (13x–30x, n = 18, 10⁻¹³–10⁻³⁰), and copper sulfate (11c–30c, n = 20, 100⁻¹¹–100⁻³⁰) were compared to n = 10 independent controls each (analogously agitated dilution medium) in randomized and blinded experiments. In none of the samples, the concentration of any element analyzed by ICP-MS exceeded 10 ppb. In the first measurement series (600 MHz), there was a significant increase in T₁ for all samples as a function of time, and there were no significant differences between homeopathic potencies and controls. In the second measurement series (500 MHz) 1 year after preparation, we observed statistically significant increased T₁ relaxation times for homeopathic sulfur preparations compared to controls. Fifteen out of 18 correlations between sample triplicates were higher for controls than for homeopathic preparations. No conclusive explanation for these phenomena can be given at present. Possible hypotheses involve differential leaching from the measurement vessel walls or a change in water molecule dynamics, i.e., in rotational correlation time and/or diffusion. Homeopathic preparations thus may exhibit specific physicochemical properties that need to be determined in detail in future investigations. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

西藏多庆错湖面变化及原因分析

论文根据1975年地形图、20世纪70年代至2009年7期MSS/TM卫星遥感资料对西藏日喀则地区东南部多庆错、嘎拉错湖泊面积变化进行分析。结果表明,多庆错和嘎拉错湖泊面积波动变化一致,2002年之前,除1976年湖泊面积较小外,其他年份多庆错、嘎拉错湖泊面积分别在80和10 km²以上,2000年湖泊面积最大,2002年之后,两个湖的面积都明显缩小。从冰川变化情况看,近34 a来,虽然该流域周围冰川与高原其他区域冰川变化趋势一致,处于消退状态,但其融水量对湖泊补给作用不明显。该流域气候变化趋势为温度升高、蒸发量减少,降水量呈波动变化。湖泊面积的涨、缩与降水量有较好的正相关关系,而与温度变化呈负相关。综合分析表明,多庆错流域湖泊变化与冰川退缩关系不密切,降水是湖面波动的主要原因。