Post-mining Soil Research Articles

Hydroseeding application using pioneer local plant seeds for coal postmining soil in Tanah Laut Regency, South Kalimantan

The research aimed to determine pioneer local plant seeds germination and growth on coal postmining soil, and to determine optimal mulch for producing great productivity. The research was conducted in two applications in a coal post mining area, Tanah Laut, South Kalimantan. The used seeds were 5 species of legumes, 3 species of grasses , and 3 species of sedges. Hydroseeding was applied by mixing seeds in mulch and spreading it on soil surface of 400 cm 2 plots (1 st application) and 10,000 cm 2 plots (2 nd application). There were five treatments in the 1 st application and repeated four times, while in the 2 nd , there were six treatments with three times repetitions. Germination rate, seedling density, plant coverage, height/length, and leaf length were observed every three days (1 st application). On 60 days after sowing, root length and plant biomass (the 1 st ), and plant coverage, height and productivity (the 2 nd ) were measured. The results showed that hydroseeding mulches could be media for pioneer local plant seeds germination and seedling growth especially for Leguminosae. While the buffalo dung could be hydroseeding mulch for Poaceae growth. Although root/shoot ratio of Cyperaceae was higher than other families, Leguminosae root developed longer as shoot growth and well adapted on postmining soil. The hydroseeding mulch composed by 720 seeds per plot and applied 4 cm in depth was optimal based on seed germination percentage. Whereas mulch with 0.2 cm depth in 2 nd application showed a higher effectivity for plant growth and productivity.

Fast accrual of C and N in soil organic matter fractions following post-mining reclamation across the USA

Reclamation of post-mining sites commonly results in rapid accrual of carbon (C) and nitrogen (N) contents due to increasing plant inputs over time. However, little information is available on the distribution of C and N contents with respect to differently stabilized soil organic matter (SOM) fractions during succession or as a result of different reclamation practice. Hence, it remains widely unknown how stable or labile these newly formed C and N pools are. Gaining a deeper understanding of the state of these pools may provide important implications for reclamation practices with respect to C sequestration.We thus investigated C, N, and plant-derived compounds in bulk soil and SOM fractions during succession in post-mining chronosequences (reclaimed with overburden or salvaged topsoil) located along a northwest to southeast transect across the USA. Our results indicate that current reclamation practices perform well with respect to rapid recovery of soil aggregates and the partitioning of C and N to different SOM fractions, these measures being similar to those of natural climax vegetation sites already 2–5 years after reclamation. A general applicability of our results to other post-mining sites with similar reclamation practices may be inferred from the fact that the observed patterns were consistent along the investigated transect, covering different climates and vegetation across the USA. However, regarding SOM stability, the use of salvaged topsoil may be beneficial as compared to that of overburden material because C and N in the fraction regarded as most stable was by 26 and 35% lower at sites restored with overburden as compared to those restored with salvaged topsoil. Plant-derived compounds appeared to be mainly related to bio-available particulate organic matter and particulate organic matter partly stabilized within aggregates, challenging the long-term persistence of plant input C in post-mining soils.

Preliminary Study of Heavy Metal (Zn, Pb, Cr, As, Cu, Cd) Contaminations on Different Soil Level from Post-Mining Bauxite Production for Aquaculture

Bauxite production and exploration give negative impact environmental modification and increasing concern pollution of heavy metals. One of an alternative to reduce the negative impact of bauxite post-mining production is by re-utilizing the abandoned bauxite land and necessary exploratory study to obtain the current environmental conditions primarily related to heavy metals in bauxite mining area. Soil and water quality samples from 5 (five) sites based on post-mining activities were used to determine concentration heavy metals of As, Cd, Pb, Zn, Cr, Cu from different soil level. They were also collected for grain size analysis including those of sand and mud percentages along with the mean, and sorting analysis. The mean grain size post-mining bauxite ranged between very fine sand to medium sand and had heterogeneous texture. The coarse grain size percentage increased towards the bottom of the soil. Total heavy metal contents for post-mining bauxite soils are 0,081 ppm, 0,245 to 0,471 ppm and 0,007 ppm for As, Pb and Cd respectively. Heavy metals for Cd, uniformly at every depth from soil level. On the other hand, Pb showed significance pattern, it was indicated every depth from soil level, the concentration of Pb was different.

Indication of rapid soil food web recovery by nematode-derived indices in restored agricultural soil after open-cast lignite mining

Open-cast lignite mining consumes arable land, which has to be restored and recultivated afterwards. This process strongly dilutes the organic carbon and nitrogen pool as well as soil biological parameters of the former soil due to mixing with the underlying subsoil and parent material before redeposition. Cultivation of alfalfa is commonly used to restore agricultural land and to refill diluted C and N pools and re-establish biologic functions. Based on nematode-derived indices, we here evaluate the development of the food web during the early recovery period with N-fixing alfalfa on post-mining soil substrates in the lignite mining district west of Cologne (Germany). Nematode-derived indices revealed a fast recovery of the soil food web during this initial alfalfa cultivation. We found evidence that the applied recultivation procedure lowers the stress and disturbance level in the soil-microbial food web and improves the trophic complexity. The fast maturing of the food web was indicated by Thornenematidae nematodes, which indicated a highly structured and stable food web already after three years of alfalfa cultivation. A declining δ15N signal of the soil indicated a strong impact of N-fixation by alfalfa. Microbial and mineral N content increased during the alfalfa cultivation period. We concluded that the rapid recovery of the soil food web might not be paralleled by an equal increase of its capacity to retain N in the soil food web. This might have implications for nitrate leaching, nitrous oxide emission, and a later agricultural recultivation with common field crops.

Translocation of Trace Elements from Sewage Sludge Amendments to Plants in a Reclaimed Area.

The goal of the study was to evaluate bioaccumulation of trace elements in plants grown in post-mining soils amended with the biosolids material. Phaseolus vulgaris was investigated on the laboratory scale, and a mixture of grasses, Melilotus albus, Beta vulgaris, Zea mays L. and Miscanthus × giganteus were evaluated on the field scale. The results of the research showed that P. vulgaris fertilized with the Carbocrash substrate was able to grow. In addition, growth was enhanced following stimulation with gibberellic acid. Transfer of trace elements should be evaluated on the plot scale. Therefore, we monitored the level of trace elements on an experimental plot in a reclaimed area. Crops plants were sown in multi-year periods. During the growing season the mixture of grasses and crop plants had a low bioaccumulation factor, which also showed a positive effect of fertilization with the Carbocrash substrate.

Relationships between respiration, chemical and microbial properties of afforested mine soils with different soil texture and tree species: Does the time of incubation matter

Respiration is a simple method to describe the overall condition of soils. Most usually, it is suggested CO2 evaluation after 7 days. Our study compared the relationship between soil respiration measured at different periods of times (one and eight weeks and cumulative respiration), as well as basic soil properties and the quantification microbial and fungal communities and their activity. We located our research on three sites with post-mine soils in Poland afforested by pine, birch and oak. Each site had soil derived from different substrate. The samples were taken from the fermentation layer (Oe) and mineral soil layer (A – at 0–5 cm beneath the Oe). In both studied layers basic soil properties such as: pH and C, N contents were analysed while soil texture was determined in A layer only. Microbial respiration was measured after each week of the eighth weeks incubation period. Microbial analyses included determination of ergosterol and phospholipid fatty acid (PLFA) profiles. Microbial respiration was nearly two time higher after the first week than the eighth week in both soil layers. Forest type and soil substrate had an effect on respiration in the Oe layer at both measurement times. Respiration in the A layer measured in the eighth week was affected only by the soil substrate. In the Oe layer, fungal decomposers play a lead role, and their activity was affected both by tree species and soil substrate. In the A layer, however, bacteria activity was predominated and was affected by tree species and substrate composition.

Organic matter transformation and porosity development in non-reclaimed mining soils of different ages and vegetation covers: a field study of soils of the zinc and lead ore area in SE Poland

Plant residue decomposition, porosity status and biological activity in heavily polluted with Zn, Pb and Cd post-mining soils were investigated in relation to natural soil in the area. The study was carried out on soils from different ages and vegetation cover. This work aimed at studying the influence of heavy metal concentration on the humus layer formation with the help of micromorphological methods. Soil samples were collected from 5 sites situated in the Zn and Pb mining area and from one site located in the vicinity but unchanged by mining works. In each site, a representative area of about 100 m2 was selected and soil samples from 5 randomly selected plots were taken from surface and subsurface layers. Chemical, micromorphological and biological analyses were conducted in order to evaluate humus transformations occurring in studied soils and to establish the main factors affecting these processes. In images taken from thin sections, we separated and measured areas covered by decomposed organic matter, plant residues and pores. Mine soils had similar pH soil values (6.7–7.1); only one natural soil was moderately acid (pH = 5.6). The soils differed in SOM content, from 30.84 to 168 g kg−1. Mine soils were contaminated with heavy metals up to 10,980 mg Zn, 5436 mg Pb and 95.2 mg Cd·kg−1. The largest amount of the medium-sized and large plant residues (18.4 and 20.5%) were found in post-mining soil covered with xerothermic flora typical of metalliferous areas. The lowest amount of small residues was found in post-mining forest soil. The diversified accumulation of plant residues reflected the organic matter decomposition ratio varying from 1.64 (post-mining soil 15% covered with calamine flora) to 62.7% (natural soil covered with forest). In the natural soil, rounded pores prevailed, while in post-mining soils, planar pores dominated. Invertase activity ranged from 1.64 to 154.2 mg of inverted sugar, and carbon of microbial biomass ranged from 5.94 to 731.2 μg g−1. Both characteristics were related to the amount of organic matter regardless of the heavy-metal pollution. The results showed that a decomposition ratio was lower in mining soils than in the natural soil, and large plant residues were accumulated in surface layers. Microbial activity was more influenced by plant cover density and diversity than by heavy metal concentration. The evolution in the organic matter form and pore shapes with the soil age and the vegetation cover was observed.

The effects of tree species and substrate on carbon sequestration and chemical and biological properties in reforested post-mining soils

The effects of tree species, parent material (substrate), and faunal bioturbation on carbon sequestration and chemical and microbial properties in soil were studied at three post-mining sites (Piaseczno, Szczakowa, and Bełchatów) in Poland that were reforested with pine, birch, oak, and alder. The samples were taken from the 0–5-cm mineral soil horizons beneath the litter layer. The samples were analyzed for pH, organic C and total N content, texture and based exchange cations. Microbial analyses included determination of ergosterol and phospholipid fatty acid (PLFA) profiles. Soil thin section was done to described faunal activity by the percentage of the soil volume occupied by earthworm casts or macrofaunal excrements. Substrate quality varied considerably among the sites; soil pH ranged from 4.0 to 6.4, and clay content ranged from 1 to 16%. The C:N ratio and other soil properties depended more on the specific combination of tree species and substrate than on tree species or substrate alone.Carbon content and C stock were positively correlated with bioturbation caused by soil macrofauna. Bioturbation was positively correlated with soil pH and the content of basic cations. In contrast, C stock was negatively correlated with the fungal to bacterial ratio (F:B ratio). Bioturbation was also positively correlated with total microbial biomass and negatively correlated with F:B ratio. Microbial biomass was positively correlated with N content and pH, both of which were negatively correlated F:B ratio.

Properties of degraded and reclaimed soils in the area of the abandoned “Jeziórko” sulfur mine (Poland)

Abstract The aim of the study was to determine some physicochemical and chemical properties of post-mining soils reclaimed in different directions, after completed sulfur exploitation by means of the borehole (Frash) method. The study was conducted in 2013 in the former Sulfur Mine „Jeziórko” located on the Tarnobrzeg Plain between Tarnobrzeg and Stalowa Wola cities (Podkarpackie Voivodeship, south Poland). It covered an area of land reclaimed as the arable or forest land. The most important problems connected with sulfur exploitation was the occurrence of a layer of solid sulfur which was previously removed. During the reclamation process, embankments and excavations were leveled through replenishing large amounts of ground, post-flotation lime, mineral fertilizers, and sewage sludge. Moreover, studies upon degraded and non-reclaimed area (by 2013) were also carried out. Examined land was characterized by granulometric composition of sands, loamy sands, and sandy loams. Re-leveling of degraded land using post-flotation lime contributed to lower levels of acidification of reclaimed soil surface. The highest contents of organic carbon and total nitrogen were found in the surface layers of the soils studied. Content of available potassium ranged from very low to average. The soils were characterized by a high content of available magnesium in the surface layers of the profiles (maximum 71.8 mg·kg−1 in soil reclaimed as forest land), while below the Mg content was usually low. Contents of individual exchangeable cations could be lined up in a following decreasing sequence: Ca2+>Na+>K+>Mg2+ Referring to the topsoil, reclaimed soils were characterized by more favorable properties (pH close to neutral, lower acidity, higher sorption capacity, higher organic carbon, total nitrogen, and available forms of phosphorus, potassium, and magnesium concentrations) as compared to non-reclaimed soil.

Changes in the Content of Humic Substances, Reaction and Sorption Properties Occurring in Reclaimed Land in Post-Mining Areas

The paper presents selected results of analyses of the properties of post-mining land of the former lignite mine „Przyjaźn Narodow” in the region of Łeknica in the Lubusz Voivodeship. The land formed in that area had very unfavourable properties: its granulometric composition (light clay sand) was susceptible to water erosion, the reaction of the formations was highly acid, the contents of total organic carbon and total nitrogen were varied and highest on the surface level of the profiles. The Ckh:Ckf ratios increased as the sampling depth increased. The development of opencast mining in the region of Łeknica (the Lubusz Voivodeship) has resulted in geomorphological changes. The post-mining land of the post-mining areas of the former lignite mine „Przyjaźn Narodow”, which started operating at the beginning of the 1970s, was subjected to reclamation processes. Reclamation in that area consisted of the following actions [7]: (a) land levelling with bulldozers; (b) soil deacidification with magnesium lime in the Zink Mill „Miasteczko Śląskie” in a dose of 50 Mg ha-1; (c) mineral fertilisation: phosphorus powder in a dose of 5 Mg ha -1, nitro-chalk in a dose of 200 kg ha -1, ammonium phosphate in a dose of 200 kg ha -1 and potash salt in a dose of 400 kg ha -1; and (d) forestation of the area with Scots pines. Accumulation of organic matter is very important for restoring fertility in post-mining soils and improving their physical, chemical and biological properties [4]. Organic matter in soils undergoes complicated processes which often depend on oxygen-environmental conditions, and produce as a result a number of mineralization products. During the process of humification, humic substances are produced, various fractions of which differ in terms of their immunity to decomposition, time of existence in the environment, and at the same time they determine soil properties [6]. Those processes occur with the participation of microorganisms. Microorganisms in soils are both decomposers participating in the decomposition of organic matter produced by autotrophic organisms and organisms responsible for soil formation processes [1]

Germination of seeds of some local pioneer plant species in different hydroseeding mulches for revegetation of post-coal mining soil

The purpose of this study was to determine the hydroseeding mulch optimum compositions for germination and productivity of a few species of local plants pioneer in the post-mining land of coal from South Kalimantan. The method used in this research was by hydroseeding technique. The species observed were Crotalaria pallida, Cajanus cajan, Kyllinga monocephala, Paspalum conjugatum, Digitaria sanguinalis and Eleusine indica . Seven variations of mulch were added to the post-mining soil. Planting seeds carried out were monoculture and polyculture. Each composition of mulch was replicated three times resulting in 147 pots. Seed germination was observed for 15 days. The results showed that all species were able to germinate and and grow well in the mulch that was added to the post-mining soil, except Kyllinga monocephala on mulch two, four and five and Digitaria sanguinalis on mulch four. The best mulch for plant growth was characterized by pH of 6.8-7.0, 47-59% organic matter, and energy ranging from 2,337.68 to 3,792.68 Kcal/kg. The highest percentage of germination was observed for Cajanus cajan (56.7%) and Crotalaria pallida (39.4%) on mulch two with germination time of eight and three days after planting. The lowest germination percentage was shown by Kyllinga monocephala at all mulch treatments (up to 30 days after planting). The optimum composition of mulch that could be recommended to accelerate the revegetation was mulch two (pH 7.06 and 59% organic matter), especially for Legum inosae, and mulch seven (pH 6.8 and 47% organic matter), especially for Poaceae and polyculture.

THE APPLICATION OF ARBUSCULAR MYCORRHIZAL FUNGI (AMF) AND COMPOST TO IMPROVE THE GROWTH OF TEAK SEEDLINGS (Tectona grandis Linn. f.) ON LIMESTONE POST-MINING SOIL

The characteristics of limestone post-mining soil are low physical, chemical and biological soil fertility, which have adverse effect on plant growth. Arbuscular mycorrhizal fungi (AMF) and compost application is expected to enhance plant growth. AMF association expand nutrients absorption area. Compost application provides nutrients and increases soil porosity, which significantly supports plant growth and AMF development. Therefore, the effectiveness of AMF or compost could be improved if both are applied simultaneously. The study was conducted to determine the effectiveness of the AMF and compost to teak seedling growth on limestone post-mining soil. A completely randomized design was applied with factorial pattern. There are 2 factors of treatment i.e AMF inoculation (K=without AMF, A= Acaulospora sp., G= Gigaspora sp., and M=Mix of Acaulospora sp. and Gigaspora sp.) and Compost percentage (K 0 =without compost, K 5 =5% compost, K 10 =10% compost, and K 15 =15% compost). The results showed AMF and compost application improved growth compared to the quality of teak seedling. Inoculation of Gigaspora sp. with 5% compost gave the best responses for stem diameter and seedling quality index. The best leaves accretion was denoted by the seedlings that were inoculated by Mix AMF with 5% compost. Inoculation of Acaulospora sp. with 15% compost had better growth response for biomass. Root-top ratio and AMF colonization were shown in seedling that was inoculated by Gigaspora sp. with 15% of compost. Gigaspora sp. with 5% compost, therefore, is the best combination for increasing seedling quality.

Growth responses of Scots pine to climatic factors on reclaimed oil shale mined land.

Afforestation on reclaimed mining areas has high ecological and economic importance. However, ecosystems established on post-mining substrate can become vulnerable due to climate variability. We used tree-ring data and dendrochronological techniques to study the relationship between climate variables and annual growth of Scots pine (Pinus sylvestris L.) growing on reclaimed open cast oil shale mining areas in Northeast Estonia. Chronologies for trees of different age classes (50, 40, 30) were developed. Pearson's correlation analysis between radial growth indices and monthly climate variables revealed that precipitation in June-July and higher mean temperatures in spring season enhanced radial growth of pine plantations, while higher than average temperatures in summer months inhibited wood production. Sensitivity of radial increment to climatic factors on post-mining soils was not homogenous among the studied populations. Older trees growing on more developed soils were more sensitive to precipitation deficit in summer, while growth indices of two other stand groups (young and middle-aged) were highly correlated to temperature. High mean temperatures in August were negatively related to annual wood production in all trees, while trees in the youngest stands benefited from warmer temperatures in January. As a response to thinning, mean annual basal area increment increased up to 50%. By managing tree competition in the closed-canopy stands, through the thinning activities, tree sensitivity and response to climate could be manipulated.

Particulate organic carbon at reclaimed and unreclaimed post-mining soils and its microbial community composition

Recovery of soil organic matter and associated microbial biomass is a fundamental precondition for successful restoration of post-mining soils. The aim is to compare the dynamics of soil C fractions and of microbial communities associated with these fractions in two chronosequences of post-mining sites with different plant communities. Soil carbon, pH, bulk density and the light fraction of particulate organic carbon (POC), free or bound in soil aggregates, were studied along two chronosequences, both covering successional ages from 10 to 50years. One chronosequence had been reclaimed by planting of alder, while the other had been vegetated by natural regrowth (Salix caprea, Populus tremula and Betula pendula). In intermediate and late successional stages, microbial community in bulk soil and POC fractions were studied using phospholipid fatty acid analysis. Soil C content increased and pH decreased with plot age, these trends being more pronounced at reclaimed sites. The light and bound POC fractions increased with age, higher values and a larger increase being found at reclaimed sites. In both chronosequences, the light fraction was an order of magnitude higher than the bound fraction. C content in both fractions increased with successional age, with higher C content at reclaimed sites. Microbial communities were more affected by the POC fraction than plot age. The bulk soil of reclaimed sites was more similar to bound POC, while the bulk soil of unreclaimed soils was similar to the light POC fraction. Observed differences correspond with a higher level of bioturbation at the reclaimed sites, which promotes faster accumulation of bound POC and drives bulk soil microbial communities closer to those of bound POC.

Phosphorus Sorption Kinetics in Reclaimed Lignite Mine Soils under Different Age Stands ofRobinia pseudoacaciaL. in Northeast Germany

The objectives of the work were to study phosphorus (P) dynamics in postmining soils under short rotation coppices at different stages ofRobinia pseudoacaciaL. growth (2, 3, 4, and 14 years old). From the results obtained, the amount of total P, total organic P, plant available P, and P stock increased with increasing age ofR. pseudoacacia. However, values were very low compared to that recommended for optimum plant growth, reflecting a general deficit in P. Additionally, the P sorption and desorption processes were investigated. The total P sorption capacity obtained from the laboratory experiments was on average, 2.5 times greater for soils under the oldestR. pseudoacaciathan values measured at the younger sites. Values of P saturation factor (α) were comparatively lower compared to that reported in the literature. This may be attributed primarily to the less P saturation of the postmining soils, coupled with rather small contents of oxalate ironFeoxand aluminiumAlox(sum of 47 mmol kg−1). Results demonstrate significant difference between 2 and 14 years oldR. pseudoacacia; thus establishing of short rotation coppice (SRC) on degraded marginal sites may be a valuable method of soil reclamations.

Distinguishing recent and fossil organic matter — A critical step in evaluation of post-mining soil development – using near infrared spectroscopy

Content of soil organic carbon (SOC) is an important parameter for monitoring of reclamation success. In coal mine soils, measurements of SOC are affected by fossil of organic matter in the overburden, such as kerogen and coal.The objective of this study was to assess the potential of near infrared spectroscopy (NIRS) coupled with partial least square analysis (PLS) for quantifying recently formed and fossil organic matter in post-mining soils near Sokolov, Czech Republic. NIR data were acquired from soil samples (n=14), where recent SOC was quantified by 14C-AMS analysis, and from artificial mixtures (n=125) of overburden, coal and material from fermentation (Oe) layer. 12 PLS analyses were performed on spectra, each separately calibrated to total C (Ctot), recent C (Crec), coal C (Ccoal) and kerogen C (Cker). All models produced correlation coefficient of cross-validation RCV>0.97. When validated using the independent validation set of soils, addition of soil samples into the calibration set improved soil predictions of Ctot and Crec (obtained from cross-validation) considerably. All four models for Ctot and Crec were classified as successful as indicated by root mean square error ranging from 0.74 to 1.11. Results showed no clear effect of grinding on predictive accuracy; thus, we conclude that particle size <2mm is sufficient for NIRS. Our results demonstrate the ability of NIRS–PLS to quantify fossil and recent carbon in soils.

Performance of the earthworm Aporrectodea caliginosa on unreclaimed spoil heaps at different successional stages

Earlier studies of post-mining soils near Sokolov, Czech Republic, showed that colonization of the spoil heaps by earthworms greatly changes the plant community composition and soil characteristics. The current study determined how colonization of heaps by the endogeic earthworm Aporrectodea caliginosa is affected by the vegetation, litter, and soil at sites of different ages. In one experiment, we measured the performance of A. caliginosa in 25-l microplots at four heaps of increasing age and successional stage (8, 15, 25, and 48 years). After 6 months, A. caliginosa number and biomass in microplots decreased in young heaps (8 and 15 years old), remained constant in the 25-year-old heap, and increased in the 48-year-old heap. In other words, A. caliginosa survival, growth, and reproduction increased with successional stage. In a second field experiment, we tested A. caliginosa performance in microplots containing different types of litter at two heaps at mid-successional stages (19 and 25 years old). After 12 months, A. caliginosa biomass and abundance were greater with grass litter than with shrub and tree litter, but were greater in the 25-year-old heap, which was dominated by shrubs, than in the 19-year-old heap, which was dominated by grasses. Together, the two experiments indicate that colonization of heaps by A. caliginosa is enhanced by succession and by remaining patches of early successional vegetation in heaps at mid-successional stages.

Fungi colonizing toxic acid soils in the dumping ground of the "Bełchatów" brown coal mine

The results of two years' studies on post-mining toxic acid soils of thc "Bełchatów" dumping grounds neutralized with chalk, ash, limestone, burnt lime, and ground phosphate rock are presented. The neutralization with ground phosphate rock and ash had the most favourable effect on the development of soil fungi.

PERTUMBUHAN BEBERAPA JENIS LEGUMINOSA PAKAN YANG DITANAM PADA MEDIA TANAH BEKAS PENAMBANGAN BATUBARA DENGAN PERBAIKAN BAHAN ORGANIK

Conditions of post coal mining areal which having losing of vegetation because of coal exploration usually have high soils acidity (pH < 5) and poor of organic matter and nutrient for plants to growing good. The mining company usually adding organic matter and planting forage legume to increase the organic matter of the soils. Objective of the research was to evaluate the growth of some forage legume that adapted on post coal mining soils dan the respone of organic matter added for post coal mining soils. Factorial Completely Randomized Design (CRD) with three replications were used in this experiment. The first factor was four kinds of forage legume, i.e. (L1 = Centrosema pubescens; L2 = Pueraria javanica; L3 = Calopogonium mucunoides; and L4 = Crotalaria juncea). The second factor was three kinds of plant medium (M0 = non post mining soil; M1 = post coal mining soil without organic matter added; and M2 = post coal mining soil with organic matter added (2% of organic carbon)). Collected data were analyzed by Analysis of Variance (ANOVA), followed by Least Significant Defference (LSD) at 5% level of sifnificant. The result of this experiment showed that application of organic matter on post coal mining soils increased the measured parameters (plant height, root lenght, leaf number, and root nodule number) of forage legume. According to the result of this experiment, concluded that Calopogonium mucunoides (L3) was more adapted on post coal mining soils than the other forage legumes, but Crotalaria juncea (L4) was more responsive for organic matter added.

Increasing Soil Water Retention with Native‐Sourced Mulch Improves Seedling Establishment in Postmine Mediterranean Sandy Soils

AbstractSeasonal drought and heavily impeded soils reduce restoration success in Mediterranean‐type postmine soils, where up to 90% seedling mortality has been observed after 2 years. To alleviate these barriers, amendments were incorporated into the soil profile of a freshly mined sand quarry. Within the quarry, three 223 m2 replicate sites contained two substrate amendments: 12% v/v native‐sourced mulch or gravel incorporated within the top 50 cm of the soil profile. Three remnant sites provided a “natural” reference system. Seeds of two autochthonous trees, Banksia attenuata (R.Br.) and B. menziesii (R.Br.) were sown across all treatments. Soil impedance, moisture, and seedling stomatal conductance were monitored for 2 years, at which point seedlings were excavated, and nutrient concentration, root morphology, and soil chemical properties were measured. Roots in all restoration treatments were restricted to the top 40 cm of the profile due to increases in soil impedance, regardless of amendment, compared to &gt;70 cm in the natural system. Seedling mortality was greatest after the second summer in the control and inorganic amendment treatments, with stomatal conductance indicating severe drought stress. Survival in the organic treatment was 24–42% greater than the control, with higher soil moisture and stomatal conductance rates 2.5 times that of the control. The increased soil water retention by a native‐sourced mulch was shown to improve postmine restoration success for these native trees.