矿业废弃地生态恢复的土壤生物肥力

土壤生物肥力水平是成功地进行矿业废弃地土地管理的关键因素之一,是矿业废弃地生态恢复和治理的重要指标。文章系统地介绍了矿业废弃地的土壤生物群落组成及功能,矿业废弃地特殊的生境对土壤生物群落的影响,也讨论了矿业废弃地生态恢复中的土壤生物的管理工作。     

铅锌矿渣场植被自然演替与基质的交互效应

矿业废弃地生态系统自然恢复的植被演替过程与机理是生态恢复研究的重要内容之一.以空间代替时间的方法,选择立地条件基本一致的4个不同自然恢复年限铅锌矿区为对象,研究黔西北土法炼锌渣场废弃地植被自然演替与矿渣基质理化性质的交互效应.结果表明： 随着堆置时间的增加,矿渣基质的营养条件明显得到改善,全氮、全磷和全钾含量极显著增加, pH上升,电导率下降,容重降低,有效铅和镉显著降低. 同时,随着恢复时间的增长,植物群落的物种丰富度、多样性指数和均匀度也相应提高.植物群落组成以多年生草本植物为主,植物群落演替在前20年较为缓慢,30年后植被群落盖度可达到53%,超过40年盖度可达87%.矿渣理化性质与物种多样性显著相关,典型变量分别是全氮、全磷和全钾;物种多样性指数与有效铅和镉呈显著负相关.土法炼锌渣场废弃地植被自然演替过程在30年后速度加快,植被生长的限制因子是营养供给不足和重金属的有效性高.     

森林土壤氮素可利用性的影响因素研究综述

近几十年来 ,人类对木材、纤维和其他森林资源需求的急剧增加 ,对森林的集约化经营管理成为必然趋势。由于大部分森林生态系统缺乏Ｎ素 ,因此施肥成为经济有效的途径。但是 ,由于森林中的Ｎ肥利用效率低于农业系统 ,且Ｎ肥生产成本较高 ,易造成环境中多余Ｎ素的污染 ,所以需要更有效的经营管理方法。要改进这类方法 ,则必须很好地理解全球各种森林生态系统的Ｎ素循环和Ｎ素可利用性[3 1] 。可利用性养分 (ａｖａｉｌａｂｌｅｎｕｔｒｉｅｎｔ)是指土壤中易被植物吸收同化的养分元素或化合物的数量[4 0 ] ,可以理解为植物利用土壤中易吸收和…     

矿业废弃地植被恢复中的基质改良

矿业废弃地植被恢复中的基质改良蓝崇钰束文圣（中山大学生命科学院,广州５１０２７５）ＡｍｅｌｉｏｒａｔｉｏｎｏｆＳｏｉｌｍｅｄｉａＤｕｒｉｎｇＶｅｇｅｔａｔｉｖｅＲｅｈａｂｉｔａｔｉｏｎｉｎｔｈｅＭｉｎｉｎｇＷａｓｔｅｌａｎｄ．ＬａｎＣｈｏｎｇｙｕ,Ｓ...     

粤东北矿山废弃地植被恢复模式探讨

矿山废弃地植被恢复是基于土壤环境改良的前提下,充分考虑植物景观的营造手段,结合生态学要求构建近自然群落。通过对广东省梅州市不同类型的矿山废弃地植被自然恢复的现场调查研究,结合国内外矿山废弃地的研究成果,指出粤东北地区矿山废弃地植物的修复原则,并提出植被恢复的具体修复方法。     

铜尾矿废弃地生物土壤结皮固氮微生物多样性

生物土壤结皮能够有效提高矿业废弃地有机质和氮的积累,促进植被的恢复.本研究基于固氮微生物的nifH基因多样性,以铜陵铜尾矿废弃地3种类型的生物土壤结皮(藻结皮、藓结皮和藻-藓混合结皮)为对象,利用变性梯度凝胶电泳(DGGE)技术研究生物土壤结皮中固氮微生物的多样性以及废弃地植物群落发育对其产生的影响.结果表明： 尾矿库裸地表面的藻结皮的固氮微生物多样性最高,其次为维管植物群落下的藻-藓混合结皮,苔藓结皮的固氮蓝藻多样性最低;随着维管植物群落高度和盖度的增加,固氮微生物多样性降低,铜尾矿废弃地的pH、水分、有机质、养分含量(氮和磷)以及有效态和总重金属浓度对固氮微生物多样性的影响均不显著.测序和系统发育分析表明,废弃地结皮中固氮微生物以蓝藻为主,主要为不具有异形胞的丝状蓝藻.
     

芒属植物重金属耐性及其在矿山废弃地植被恢复中的应用潜力

芒属植物重金属耐性强,并且是重要的能源植物,其在矿山废弃地植被恢复中的应用备受关注.芒属植物对多种重金属耐性强,但不属于重金属超累积植物.目前的研究认为,根系代谢能力强、根际存在多种共生微生物及抗氧化和光合作用能力强是芒属植物重金属耐性强的重要原因,但更为全面的耐性机理需要深入研究.芒属植物在矿山废弃地植被恢复的应用潜力大,可以清除土壤重金属、改善土壤性质和促进生物多样性发展.本文总结分析了芒属植物生物学特性、重金属耐性特点、机理及其在矿山废弃地植被恢复中的应用潜力,提出了应用芒属植物进行矿山废弃地植被恢复的基本思路,并对芒属植物的重金属耐性机理及应用的未来研究方向进行展望,以期为利用芒属植物开展矿山废弃地植被恢复提供借鉴.     

陇中黄土区坡面整地和植被类型对土壤化学性状的影响

合理的坡面整地和人工植被恢复能够改善土壤状况,进而促进植被生长和生境改善。在半干旱黄土高原地区,研究不同植被类型和整地方式下的土壤属性变化规律,对于揭示整地-植被-土壤之间的相互作用机制有重要意义。基于外业采样和室内测定的方法,测定了样品的有机质、全氮、全磷、全钾、碱解氮、速效钾、有效磷和酸碱度,对比和分析黄土高原小流域不同整地方式和植被类型下的土壤养分特征。结果表明:(1)土壤养分变化的总体规律是明显的表聚性,土壤养分含量随土层的增加而减少,0—1m养分平均含量只有表层含量的43.1%—86.8%,除此之外全磷、全钾养分含量还具有波动性、富集性等特点;(2)整地和植被类型对土壤养分的影响:整地方式下养分含量依次为:水平沟、水平阶鱼鳞坑反坡台,植被类型养分对比结果:柠条油松山杏侧柏,同时发现整地方式对速效养分的影响较大,而植被恢复对全量养分的影响占主导优势;(3)植被对不同土壤养分的吸收利用响应:分析植被的养分利用特点,发现侧柏对磷素的消耗较大,柠条对钾素的消耗较大,并且发现有机质含量存在波动层、渐变层和稳定层等分布特征。     

北方地区铁矿废弃地基质改良及植被恢复技术

北方地区铁矿围岩硬度大,采选后形成大面积立地条件恶劣的排岩场。该类废弃地主要由砂砾组成,粉砂含量占比99%左右,持水保肥能力差,养分贫瘠。通过添加城市生活污泥、粉煤灰及黏土配比的人工基质进行矿地土壤改良。结果表明:人工基质中总氮含量为4.37~6.60 g·kg~(-1),有效磷、有效钾含量也属于高肥力水平,且重金属Zn、Ni、Cr、Mn和Hg含量低;采用鱼鳞坑模式种植乔灌木刺槐与棉槐,生长2年后,植株茎干、根系生长迅速,周围有大量草本植物出现,植被盖度显著增加;矿渣中重金属主要富集在植物根部,且随着生长时间的增加,向地上转移的量越来越少;在铁矿排岩场植被恢复2~3年后,废弃地肥力及养分的补充是制约其恢复效果的关键。     

黄土丘陵沟壑区退耕地土壤养分因子对植被恢复的贡献

为了探求各土壤养分因子对植被恢复贡献的大小．利用因子分析(Factor analysis)对黄土高原丘陵沟壑区退耕地植被恢复中的土壤养分进行了多元统计分析,定量研究了土壤养分环境对植被恢复的作用。结果表明：住所选取的6个土壤养分因子中,土壤有机质、有效N、全P和速效P对植被恢复的贡献较大．是限制该地区植被恢复的主导因素,其它养分因子的贡献相对较小。根据土壤养分因子间的相关系数,土壤有机质与全N和有效N呈显著相关。因此,在评价土壤养分因子对植被恢复贡献大小时．选取土壤有机质、氮和磷的含量作为评价指标,不但节省了时间和财力,而且有助于植被恢复的快速评价。     

中国矿业废弃地的复垦对策研究(Ⅰ)

述评了中国矿业废弃地的现状及其环境影响,系统总结了几十年来中矿业废弃地复垦的理论研究、法规建设和实践方面的进展情况和不足之处。同时指出：根据中国国情,深入研究不同类型废弃地复垦的技术体系和模式、卓有成效的促成理论研究和实践的结合,修订完善现有的复垦与生态重建的政策法规是中国矿业废弃地复垦工作的当务之急。     

采矿废弃地的生态恢复与可持续景观设计

采矿废弃地是剧烈人为干扰下的一种特殊景观类型 ,其生态系统结构与功能退化严重 ,同时其使用功能和美学价值被破坏。通过生态恢复和重建促使采矿废弃地的生态和经济价值再生 ,并通过景观设计赋予利用和美学的价值 ,对区域生态系统的健康、地方经济可持续发展以及人民的生活水平具有十分重要的意义。通过分析采矿废弃地的景观生态特征和环境影响 ,对生态恢复与重建的各种工程与生物措施以及可持续利用途径进行综述 ,并通过介绍和分析国内外一些案例 ,进而对采矿废弃地景观设计的基本原则进行总结。     

鸡粪改良铜尾矿对3种豆科植物生长及基质微生物量和酶活性的影响

基质改良和耐性植物种选择是重金属矿业废弃地人工生态恢复的关键。通过室内盆栽试验研究不同比例腐熟鸡粪改良铜尾矿后对3种豆科植物决明(Cassia tora)、田菁(Sesbania cannabina)、菽麻(Crotalaria juncea)生长和尾矿基质中土壤微生物量C、N及过氧化氢酶、碱性磷酸酶、脲酶和脱氢酶活性的影响。结果表明:添加鸡粪改良处理后3种植物茎叶生物量、根系生物量和体内总磷含量均有提高,植物体内总氮含量则只有菽麻明显增加。添加鸡粪可提高尾矿基质中微生物量C以及脲酶和脱氢酶活性,其中菽麻生长的尾矿基质中微生物量C含量增加最显著。尾矿基质中微生物量C与基质中总氮、有效磷呈显著正相关,菽麻生长的尾矿基质中微生物量C与基质中有效态Cu、Zn呈显著负相关。田菁、菽麻生长的尾矿基质中脲酶、脱氢酶与基质中总氮、有效磷呈显著正相关,决明、菽麻生长的尾矿基质中脱氢酶与基质中微生物量C呈显著正相关,决明生长的尾矿基质中脲酶、脱氢酶与基质中有效态Zn呈显著负相关。综合分析表明,铜尾矿∶鸡粪=250∶1的处理方式可作为鸡粪改良铜尾矿基质较好的一种比例模式,该处理方式下菽麻可作为铜尾矿生态修复优选植物种。     

Phosphorus deprivation affects composition and spatial distribution of membrane lipids in legume nodules

In legumes, symbiotic nitrogen (N) fixation (SNF) occurs in specialized organs called nodules after successful interactions between legume hosts and rhizobia. In a nodule, N-fixing rhizobia are surrounded by symbiosome membranes, through which the exchange of nutrients and ammonium occurs between bacteria and the host legume. Phosphorus (P) is an essential macronutrient, and N₂-fixing legumes have a higher requirement for P than legumes grown on mineral N. As in the previous studies, in P deficiency, barrel medic (Medicago truncatula) plants had impaired SNF activity, reduced growth, and accumulated less phosphate in leaves, roots, and nodules compared with the plants grown in P sufficient conditions. Membrane lipids in M. truncatula tissues were assessed using electrospray ionization–mass spectrometry. Galactolipids were found to increase in P deficiency, with declines in phospholipids (PL), especially in leaves. Lower PL losses were found in roots and nodules. Subsequently, matrix-assisted laser desorption/ionization–mass spectrometry imaging was used to spatially map the distribution of the positively charged phosphatidylcholine (PC) species in nodules in both P-replete and P-deficient conditions. Our results reveal heterogeneous distribution of several PC species in nodules, with homogeneous distribution of other PC classes. In P poor conditions, some PC species distributions were observed to change. The results suggest that specific PC species may be differentially important in diverse nodule zones and cell types, and that membrane lipid remodeling during P stress is not uniform across the nodule.

ESI–MS and matrix-assisted laser desorption ionization–mass spectrometry imaging reveal alterations in Medicago truncatula nodules membrane lipid composition and spatial distribution in phosphorus deficiency.     

Benefits of mycorrhizal inoculation to ecological restoration depend on plant functional type,restoration context and time

Mycorrhizal inoculation can enhance outcomes of ecological restoration, but the benefits may be context-dependent. Here, we performed a meta-analysis of field studies to elucidate conditions in which adding mycorrhizal fungi enhances restoration success. We found inoculation increased plant biomass by an average effect size of 1.7 in 70 independent comparisons from 26 field-based studies, with the largest increases to N-fixing woody plants, C4-grasses and plants growing in soils with low plant-available P. Growth responses to inoculation increased with time for the first 3 yr after inoculation, especially for N-fixing woody plants and plants growing in severely altered soils. We found that mycorrhizal inoculation increased species richness of restored plant communities by 30%, promoted establishment of target species, and enhanced similarity of restored to reference communities. We conclude that the addition of mycorrhizal fungi to restoration sites can facilitate rapid establishment of vegetation cover, and restoration of diverse plant communities more akin to reference sites.     

Nitrogen accumulation in kaolin mining wastes in Cornwall III. Nitrogenous fertilisers

Summary In the establishment of a grass cover on china clay waste it is necessary, as in most land restoration, to supply fertiliser nitrogen in substantial amounts. However the objective of nitrogen accumulation is restricted in south west England by severe leaching. A series of experiments were devised to investigate the nitrogen retention from a range of fertiliser sources.When fertiliser-N was applied to established swards, three times as much nitrogen (about 90 per soil and vegetation at the end of the first season of establishment. Sodium nitrate was especially susceptible to leaching, in contrast to sources containing ammonium. Slow-release formulations and organic materials produced a lower sward growth throughout the first growing season but tended to give higher levels of residual-N in the sand waste.When fertiliser-N was applied at seeding less than 30 per cent of the nitrogen was retained in the cent of that applied) was retained. Most of this nitrogen was retained in the sand waste. There was little difference between different types of fertiliser: the main effect was to alter the amount of nitrogen in herbage tissues.Plant growth and a healthy grass sward could only be sustained in the absence of a legume component by repeated applications of fertiliser-N. When applications were discontinued sward degradation was shown by decreases in biomass. Losses in nitrogen from the sward biomass were more than accounted for by an increase in the nitrogen content of the sand waste. These results indicate that once fertiliser-N is retained by the sward ecosystem on sand waste, there are few further losses, presumably because of rapid microbial immobilisation of nitrogen in the sand waste.In view of the expense of land restoration using numerous maintenance applications of nitrogen, it is clear that legumes must be included in the seeds mixture for the reclamation of kaolin mining wastes in Cornwall. However, legumes are difficult to establish and more susceptible to drought than grass species. Results from these trials suggest that slow-release nitrogen fertilisers could enable a controlled level of grass growth, thereby avoiding competition between the legume and grass components. Alternatively grass swards could be rapidly established to stabilise the sand waste using soluble ammonium salts, and in the second season oversown with legumes.     

Invasion of temperate deciduous broadleaf forests by N-fixing tree species – consequences for stream ecosystems

Biological invasions are a major threat to biodiversity and ecosystem functioning. Forest invasion by alien woody species can have cross-ecosystem effects. This is especially relevant in the case of stream–riparian forest meta-ecosystems as forest streams depend strongly on riparian vegetation for carbon, nutrients and energy. Forest invasion by woody species with dissimilar characteristics from native species may be particularly troublesome. The invasion of temperate deciduous broadleaf forests with low representation of nitrogen (N)-fixing species by N-fixers has the potential to induce ecosystem changes at the stream level. Although effects of tree invasion on stream ecosystems have been under assessed, knowledge of native and invasive tree characteristics allows prediction of invasion effects on streams. Here we present a conceptual model to predict the effects of forest invasion by alien N-fixing species on streams, using as a background the invasion of temperate deciduous broadleaf forests by leguminous Acacia species, which are among the most aggressive invaders worldwide. Effects are discussed using a trait-based approach to allow the model to be applied to other pairs of invaded ecosystem–invasive species, taking into account differences in species traits and environmental conditions. Anticipated effects of N-fixing species invasions include changes in water quality (increase in N concentration) and quantity (decrease in flow) and changes in litter input characteristics (altered diversity, seasonality, typology, quantity and quality). The magnitude of these changes will depend on the magnitude of differences in species traits, the extent and duration of the invasion and stream characteristics (e.g. basal nutrient concentration). The extensive literature on effects of nutrient enrichment of stream water, water scarcity and changes in litter input characteristics on aquatic communities and processes allows prediction of invasion effects on stream structure and function. The magnitude of invasion effects on aquatic communities and processes may, however, depend on interactions among different pathways (e.g. effects mediated by increases in stream nutrient concentration may contrast with those mediated by decreases in water availability or by decreases in litter nutritional quality). A review of the literature addressing effects of increasing cover of N-fixing species on streams suggests a wide application of the model, while it highlights the need to consider differences in the type of system and species when making generalizations. Changes induced by N-fixing species invasion on streams can jeopardize multiple ecosystem services (e.g. good quality water, hydroelectricity, leisure activities), with relevant social and economic consequences.     

自然演替过程中铜尾矿土壤酶活性的变化

铜陵矿区堆放了大量不同时期的铜尾矿,形成大量铜尾矿废弃地,其中的大部分铜尾矿废弃地处于自然生态恢复状态。并形成典型的原生演替系列。为探讨废弃地自然生态恢复中不同演替阶段植物群落变化与土壤酶活性变化的关系,对铜陵3处不同时期弃置的尾矿废弃地进行了调查。随着自然生态系统演替的进行,尾矿中土壤酶活性逐步提高,维管植物群落下尾矿中土壤酶活性〉隐花植物结皮下尾矿中土壤酶活性〉裸地处土壤酶活性;位于植物群落下的尾矿废弃地中脲酶、碱性磷酸酶、过氧化氢酶的活性从表层至下层逐渐降低。不同植物群落对尾矿中土壤酶活性影响有很大差异,位于木贼群落下的尾矿中几种土壤酶的活性高于位于白茅群落和中华结缕草群落下的尾矿中酶的活性。相关分析表明,土壤酶活性与有机质、总N表现出显著的正相关。     

Seedling growth of four fire-following Mediterranean plant species deprived of single mineral nutrients

1. Anthyllis vulneraria, Cistus creticus, Hippocrepis unisiliquosa and Pinus brutia are frequent post-fire colonizers whose seedlings are subjected to the mineral conditions imposed by ash in the early stages of growth. We test the hypothesis that the effective internal supply of mineral elements in the seeds of these species may complement the external availability of specific nutrients.
2. Newly germinated seedlings were grown in nutrient solutions, each deficient in one of the following elements: nitrogen, phosphorus or potassium. Control treatments consisted of full nutrients and distilled water. Seedling growth was monitored over 12weeks. The final dry masses of the seedlings were taken as a measure of the availability of each element from the seeds' own stored reserves.
3. For the two legume species nitrogen was the most limiting element followed by phosphorus. Potassium deficiency had no effect on the final legume dry biomass. For Cistus, the order was nitrogen followed by potassium, while phosphorus deprivation had no effect on growth during the 12weeks of the experiment. Deprivation of single minerals had no significant effect on seedling growth of Pinus over the same period. The two legumes and Cistus when denied nitrogen had relatively greater relative root ratios than control plants.
4. The relative seedling requirements of each species for early external supplies of the various nutrients for establishment in the field are discussed with reference to the adaptation of the four species to post-fire regeneration.