生态环境质量物元可拓评价及实例分析

生态环境质量评价属于环境质量评价的重要方面。为了探索建立生态环境质量评价的方法，尝试运用物元可拓的方法来建立生态环境质量评价模型，并且通过用该方法对土壤生态环境质量评价实例验证物元可拓方法的可行性，得到该土壤生态环境质量评价等级值为3．73。从而为尚处在探索发展阶段的生态环境质量评价方法提供一种新思路。     

It's a dirty job but someone has to do it: The role of marine benthic macrofauna in organic matter turnover and nutrient recycling to the water column

Benthic macrofaunal populations through their feeding, bioturbation, burrow construction and sediment irrigation activities have profound influences on organic matter inputs to marine sediments (biodeposition) and on the vertical distribution of deposited organic matter within the sediment. These effects in turn influence the rates and pathways of organic matter mineralisation, and element cycles. Similarly, bioturbation, burrow construction and burrow irrigation are major determinants of sediment-water column fluxes of oxygen and nutrients.

In this review, I discuss the influences of the different benthic macrofaunal feeding (functional) groups on mineralisation processes and sediment-water column fluxes of particulate and dissolved nutrients. How these effects influence diagenic processes, the balance between aerobic and anaerobic processes, and the redox status of the surficial sediments. Finally, I discuss some of the limitations of the predominantly laboratory techniques which have been used to study “macrofaunal effects” and how this hinders the inclusion of the effects in quantitative sediment biogeochemical models.     

不同氮肥与磷肥的互作效应

利用盆栽试验研究了潮土中不同氮肥与磷肥的互作效应，结果表明：不同氮肥与磷肥的配合施用对潮土中油菜的生长和养分吸收有显著的交互作用。生长初期，施氮并不能促进、甚至会抑制油菜的生长，氯化铵较其它氮肥作用突出。随着生长期的延长，氮肥对油荣生长的促进作用逐渐显现，但氯化铵的促进作刚仍低于其它氮肥。植株养分累积受不同氮肥影响的规律与植株干物质累积表现的规律基本一致。土壤有效磷含最受不同氮肥影响较小，而水溶性磷含量因施用不同氮肥表现出显著的差异，特别是在生长初期的土壤中。相关分析结果表明，油菜生长初期的干物质质量与土壤水溶性磷含量达到极显著相关（r=0．727^＊＊）。因此推测，不同氮肥对油菜生长的影响可能因氮肥降低土壤中磷的有效性所致，这些结果对今后的合理施肥提供了重要的参考依据。     

Dissolved Organic Matter in Forest Soils: Sources, Complexing Properties and Action On Herbaceous Plants

Dissolved organic matter (DOM) is an important component of plant-soil systems. Its essential role in soil solution chemistry, soil-forming processes and its effects on biota, including soil fauna, bacteria, fungi and plants, is extensively documented in literature. in this contribution several forest leaf litter types are compared as sources of DOM and the released organics are subjected to gel permeation chromatography to reveal their molecular-size distribution. Moreover, complexing properties, as an indication for the podzolization potential of the litter leachates, were established. the occurrence and properties of DOM in different soil horizons were monitored beneath a stand of Scots pine. the effects of the different groups of soluble organics including phenolic, fulvic and humic acids, and of water-extractable humic substances on the performance of herbaceous plants of the forest floor are briefly reviewed.     

High Cu and Cd pollution in sediments from Sisimiut, Greenland. Adsorption to organic matter and fine particles

High concentrations of Cu of up to 200 mg/kg, and Cd of up to 4.0 mg/kg, were found in sediments from the aquatic environment around Sisimiut, Greenland. These concentrations are four times higher than the limiting concentration where toxicological effects are expected. The pollution could be linked to human activities in Sisimiut, a link that have not been investigated previously in Greenland. Except from the most polluted samples there was good correlation between heavy metal concentration and organic matter. Also some relationship between fine fraction and heavy metal concentration was observed.     

Dynamics of soil organic matter in primary and secondary forest succession on sandy soils in The Netherlands: An application of the ROMUL model

We applied the simulation model ROMUL of soil organic matter dynamics in order to analyse and predict forest soil organic matter (SOM) changes following stand growth and also to identify gaps of data and modelling problems. SOM build-up was analysed (a) from bare sand to forest soil during a primary succession in Scots pine forest and (b) on mature forest soil under Douglas fir plantations as an example of secondary succession in The Netherlands. As some of the experimental data were unreliable we compiled a set of various scenarios with different soil moisture regime, initial SOM pools and amount and quality of above and below ground litter input. This allowed us to find the scenarios that reflect the SOM dynamics more realistically. In the Scots pine forest, total litter input was estimated as 0.50 kg m⁻² year⁻¹. Two scenarios were defined for the test runs: (a) forest floor moisture regimes—‘dry, mesic and hydric’ and (b) augmenting a root litter pool with three ratios of needles and branches to roots: 1:1, 1:1.5 and 1:2.0. The scenario finally compiled had the following characteristics: (a) climate for dry site with summer drought and high winter moisture of forest floor; (b) a litter input of 0.25 kg m⁻² year⁻¹ above ground and 0.50 kg m⁻² year⁻¹ below ground; (c) a low nitrogen and ash content in all litter fall fractions. The test runs for the estimation of the initial SOM pools and the amount and proportion of above and below ground litter fall were also performed in the Douglas fir plantation. The inputs of above ground litter tested in various combinations were 0.30 and 0.60 kg m⁻² year⁻¹, and below ground litter 0.30, 0.60 and 0.90 kg m⁻² year⁻¹. The scenario that fitted the experimental data had an SOM pool of 20–25 kg m⁻², an aboveground litter input of 0.6 kg m⁻² year⁻¹and a below ground litter input of 0.9 kg m⁻² year⁻¹. The long-term simulation corresponded well with the observed patterns of soil organic matter accumulation associated with the forest soil development in primary and secondary succession. During primary succession in Scots pine forest on dry sand there is a consistent accumulation of a raw humus forest floor. The soil dynamics in the Douglas fir plantation also coincide with the observed patterns of SOM changes during the secondary succession, with SOM decreasing significantly under young forest, and SOM being restored in the older stands.     

不同有机物料在潮棕壤中有机碳分解进程

用尼龙网袋法研究了特定年度中，不同月份间有机物料在潮棕壤旱田、水田中有机碳分解速率及C／N变化。结果表明，4种物料(玉米秸和玉米根，水稻秸和水稻根)在潮棕壤地区温度、湿度适宜的前3个月(1999年7—月)迅速分解，之后进入缓慢分解阶段，其中根的分解残留率始终高于秸秆。经计算约有2／3的玉米根和稻根腐解产物残留在土壤里；分解至试验结束。所有物料的C/N比都趋于一致，约在10—13之间，与土壤腐殖质的洲比非常相近，说明这些物料已基本完成其腐殖化过程，而成为较稳定的有机组分、这对增加土壤有机质、培肥土壤非常重要。     

可溶性有机物对土壤中主要有机污染物环境行为的影响

概括了环境中可溶性有机物的特点，并系统总结了当前国内外关于可溶性有机物对土壤中主要污染物环境行为的影响的研究进展。阐述了可溶性有机物对农药、多环芳烃在土壤中的吸附、解吸及分配等环境行为所起的作用。最后指出了该方面研究存在的问题及今后应加强的方向。     

Canopy structure versus physiology effects on net photosynthesis of mountain grasslands differing in land use

The present paper aims at investigating how changes in canopy structure and species physiology associated with the abandonment of mountain meadows and pastures affect their net photosynthesis. For this purpose, a multi-layer vegetation–atmosphere transfer (VAT) model is employed, which explicitly takes into account the structural and functional properties of the various canopy components and species. Three sites differing in land use are investigated, a meadow, a pasture and an abandoned area. Model simulations agree reasonably with measured canopy net photosynthetic rates, the meadow featuring the highest daily net photosynthesis, followed by the pasture and, finally, the abandoned area. A detailed process analysis suggests this ranking to be mainly due to bulk canopy physiology, which decreases from the meadow to the pasture and the abandoned area, reflecting species composition and species-specific photosynthetic capacities. Differences between the canopies with regard to canopy structure are found to be of minor importance. The amounts of green, photosynthetically active plant matter are too similar at the three sites to be a major source of variation in net photosynthesis. Large differences exist between the canopies with regard to the amount of photosynthetically inactive phytoelements. Even though a model analysis showed them to be potentially important, most of them are accumulated close to the ground surface, where they exert little influence on canopy net photosynthesis.     

Toxic metals status in human blood and breast milk samples in an integrated steel plant environment in Central India

Owing to its unique nutritional and immunological characteristics, human milk is the most important food source for infants. Breast milk can, however, also be a pathway of maternal excretion of toxic elements. Selected toxic elements (As, Pb, Mn,a Hg and Cd) were determined in human breast milk and blood samples obtained from 120 subjects related to an integrated steel plant environment located in central India. Samples of breast milk and blood from subjects living outside the steel plant environment were also analyzed for comparative study. Higher levels of these toxic elements were found in blood samples as compared to breast milk samples. Plant workers showed the higher presence of these metals in their breast milk and blood samples compared to the residents of the area and the subjects living outside the industrial environment, respectively. Mn, Pb and Hg have shown a higher tendency to associate with blood and breast milk than As and Cd. The order of occurrence of these metals in blood and milk samples thus found is Mn > Pb > Hg > As > Cd.