BY Dr. A.N. Singh Department of Botany, Panjab University Chandigarh 29 th May, 2015

Transcription

1 17 th International Symposium on Landscape and Landscape Ecology, May, 2015, Nitra, Slovakia Comparative Restoration Potential of certain Native and Exotic Woody Species planted on degraded mine habitats in a dry Tropical Environment, India: Implications to reestablishing a new forest landscape BY Dr. A.N. Singh Department of Botany, Panjab University Chandigarh ansingh@pu.ac.in 29 th May,

2 All is not well Four main problems: 1. Food, water and energy security 2. Loss of biological diversity 3. Global climate change 4. Sea-level rise First and second problems are directly related with human activities 2

3 Degraded landscape : Coal mine spoil Demand for electricity Open cast coal mining operations degrade significant areas of land and replace existing ecosystems with undesirable waste materials in the form of mine spoil. Mine spoils are impoverished habitats. Pedologically, chemically and biologically poor. 3 Source: Singh et al. 2004; Forest Ecology and Management, 187: 49-60

4 Mining activities: 4

5 Why ecological restoration of mining landscape is Important? Slow process in natural recovery. Soil erosion To develop self sustainability. Acceleration of natural recovery. Climate, vegetation and soil are interrelated and determine the quality of an ecosystems. Soil is one of the primary agents in determining vegetation development. Biodiversity development contributes organic matters (OM) in the soil. Development of OM pool serve as nutrient source for sustaining vegetation and soil redevelopment. Rehabilitated mine soils have a high potential to sequester C through biomass production and accumulation of soil organic matter in the soil. 5 Source: Singh et al. 2006; Land Degradation and Development,17: 13-21

6 CONTD :Relevance : Present, Past and Future More than 80,000 ha of land are under various types of mining activities in our country. Ecosystem destruction by mining for coal quarrying for minerals and other process to meet demands of industries is an inevitable part of civilization. It can not be stoped. Due to mining operation, about 6000 ha forest area is likely to be affected in the Singrauli region on Vindhyan high lands of India. Every million tonne of coal extracted by surface mining methods damage a surface area of about 4 ha in India. Primary aim is to restore soil quality by introduction of desirable plant species, once soil is restored, no problem to make ecosystem in to functional and most productive socioeconomic and ecological state. 6 Source: Singh et al. 2002, Current Science, 82: ; Singh, 2015, communicated in Restoration Ecology)

7 Basic concept of the Soil Restoration Soil plays a fundamental and irreplaceable role in the biosphere because it governs plants productivity of terrestrial ecosystem, allows the completion of the biogeochemical cycles. Soil harbours high population density and enormous microbial diversity under a tremendous range of physical and chemical conditions. Agents of the Soil redevelopment Probably the soil micro-flora is the results of more than 3.5 billions years of evolution, and a co-evolution with plant species to which rhizosphere is associated. 7 Source: Singh et al. 1995; Interim Report of S& T project

8 Case study : Objectives To analyze certain plant functional traits such as growth, biomass production and their impacts on soil redevelopment and carbon sequestration efficiency under different plantations (mono and mixed culture) of certain native species. To evaluate the efficiency of biodiversity development (species recruitment) and soil carbon sequestration under mono and mixed culture plantations. 8

9 Questions were asked: Are the direction and rate of soil redevelopment and carbon sequestration efficiency different for monoculture and mixed culture plantations? Are species recruited in a particular order, and is this order different for sites under plantations of different species (e.g. leguminous vs. nonleguminous)? Is soil carbon sequestration efficiency of planted species regulated by plant functional traits (growth and productivity)? 9

10 hypotheses were tested: Native species have more beneficial effect in long term on soil redevelopment process and recruitment of biodiversity. Rapidity of biodiversity reconstruction is related with the rate of soil redevelopment. Soil carbon sequestration rate is related to the rate of net primary productivity of planted species, soil redevelopment and rate of biodiversity reconstruction. 10

11 Study site 11

12 Before mining Mine spoil dump After mining 12 Source: Singh et al. 1995; Interim Report of S& T project

13 Planted Species Mono-culture- Native 1. Albizia lebbeck 2. Albizia procera 3. Azadirachta indica 4. Dalbergia sissoo 5. Pongamia pinnata 6. Shorea robusta 7. Tectona grandis 8. Dendrocalamus strictus Mono-culture-Exotic 1. Alcacia auriculiformis 2. Casuarina equisetifolia 3. Eucalyptus hybrid 4. Grevillea pteridifolia Mixed-culture 1. A. lebbeck + A. catechu 2. A. indica + P. emblica 3. D. sissoo + T. grandis 4. D. strictus + T. grandis 13

14 Albizia lebbeck Albizia procera 14 Tectona grandis Dendrocalamus strictus

15 Exotic species A. auriculiformis C. equisetifolia C. siamea G. pteridifolia 15

16 Experimental Design Planted species Native: Albizia lebbeck ; Albizia procera ; Tectona grandis; Dendrocalamus strictus; Acacia catechu; Azadirachta india; Dalbergia sissoo; Gmelina arborea; L. leucocephala; P. pinnata and T. bellirica Some Exotic plantations: Acacia auriculiformis; Casuarina equisetifolia; Cassia siamea and Grevillea pteridifolia and Eucalyptus hybrid Plantation period: These species were raised in 1990, 1991 and 1993 by planting 7-8 month old nursery raised seedlings. Plot Size: 20 m x 20 m Pit size: 40 cm x 40 cm x 30 cm Spacing Size: 2 m x 2 m 16

17 Parameters: A: Vegetational characters Vegetation data were quantitatively analyzed for phyto-sociological study such as frequency, density, basal cover, above ground biomass for the estimation of IVI. 17 Field work: i) Collection of plants naturally colonized in different revegetation model plots in different season and time. ii) Estimation of Biomass production and net primary production of planted species iii) Quantitative analysis of botanical composition of the vegetation developed in different plantation plots. Laboratory work: i) Identification and preparation of list. ii) Analysis of field collected data for phyto-sociological characterization. B: Soil characters Field work: Collection of samples from mine spoils of different plantation plots as well as bare and fresh mine spoil. Laboratory work: i) Processing of the collected soil samples for various physical and chemical analyses. ii) Calculation and statistical analysis of the collected data and characterization of spoils. iii) Estimation of Soil carbon sequestration rates under different plantation plots. iv) Changes in physico-chemical properties of soils due to plantations at different ecological models will be assessed.

18 Methodologies used: A: Vegetational characters B: Soil characters Biomass estimation by allometric regression equations (harvest method) as described by Singh and Singh (1991). Water holding capacity by perforated circular brass boxes (Piper 1944) and particle size distribution by sieving method (Piper1966). Net primary production was estimated using diameter increments and biomass data as described by Chaturvedi and Singh (1987). Phytosociological parameters such as IVI, frequency, density, abundance, richness, species diversity, evenness, Alpha-diversity will be estimated by adopted standard methodologies. Soil organic carbon by dichromate oxidation and titration with ferrous ammonium sulphate (Allen et al. (1986), Kjeldahl N and total P by digestion procedure (Jackson 1958). Ammonium-N by phenate (APHA 1985) and nitrate-n by PDSA method (Jackson 1958). Po4-pi by ammonium molybdate-stannous chloride method (Sparling et al.1985). N- mineralization, nitrification rates by buried bag technique (Eno 1960). Microbial biomass C, N and P were determined by chloroform fumigation and extraction methods (Brookes et al. 1982, 1985a, b, Vance et al. 1987). 18

19 Total soil organic carbon (SOC) and stock under monoculture plantations of certain native woody species on coal mine spoil. Values (mean ± 1SE) are means of three replicate plots. Each rows suffixed with different letters are significantly different with each other at p < 0.05 Parameters 5- years 17- years Soil organic carbon (%) A. lebbeck ± a ± b A. procera ± a ± b T. grandis ± a ± b D. strictus * ± a ± b A. indica ± a ± b D. sissoo ± a ± b P. pinnata ± a ± b S. robusta ± a ± b Carbon stock (kg ha -1 ) A. lebbeck ± a ± b A. procera ± a ± b T. grandis ± a ± b D. strictus * ± a ± b A. indica ± a ± a D. sissoo ± a ± b P. pinnata ± a ± b S. robusta ± a ± b 19

20 Total soil organic carbon (SOC) and stock under monoculture plantations of certain exotic woody species on coal mine spoil. Values (mean ± 1SE) are means of three replicate plots. Each rows suffixed with different letters are significantly different with each other at p < 0.05 Parameters 5- years 17- years Soil organic carbon (%) Carbon stock (kg ha -1 ) A. auriculiformis ± a ± b C. equisetifolia ± a ± b E. hybrid ± a ± b G. pteridifolia ± a ± b A. auriculiformis ± a ± b C. equisetifolia ± a ± b E. hybrid ± a ± b G. pteridifolia ± a ± b 20

21 Total soil organic carbon (SOC) and stock under mixed-culture plantations of certain native woody species on coal mine spoil. Values (mean ± 1SE) are means of three replicate plots. Each rows suffixed with different letters are significantly different with each other at p < Soil organic carbon (%) 5- years 17- years A. lebbeck + A. catechu ± a ± b A. indica + P. emblica ± a ±0.027 b D. sissoo + T. grandis ± a ± b D. strictus + T. grandis ± a ± b Carbon stock (kg ha -1 ) A. lebbeck + A. catechu ± a ± b A. indica + P. emblica ± a ± b D. sissoo + T. grandis ± a ± a D. strictus + T. grandis ± a ± b 21 Total carbon and nutrient stock in < 2 mm soil aggregates size (kg C ha-1) = [C (g kg-1) corrected BD (kg m-3) d (m) 104 (m2 ha-1)]/1000 Where, C = concentration of carbon nutrient, BD = corrected bulk density, d = specific thickness layer of soil sample (Singh et al. 2006).

22 Current more challenges of Ecological restoration of coal mine spoil: 1. Entry of alien species as invader in plantations stand: a)hyptis suaveolens (L.) Poit. (Lamiaceae, commonly known as American mint, bush tea, Vilayati Tulsi ). b) Lantana camara (L.) (Verbenaceae, commonly known as Lantana weed and Raimunia). 2. Human intervention: for livelihood, fire, house hold purposes. 3. Grazing: Frequent grazing by cattle, no fenced and protection. 22

23 a) Hyptis suaveolens- an annual weed 23

24 Invaded by Hyptis in plantation stands: D. sissoo D. sissoo 24

25 b) Lantana camara- a shrub 25

26 2. Human intervention: 26

27 3. Grazing: 27

28 Importance value index (IVI) of herbaceous vegetation under monoculture (native and exotic) and mixed culture plantations of woody species on coal mine spoil. Values are means of three replicate plots Parameters Plantation age (year) Mono-culture (native) Hyptis (+) Hyptis (-) Hyptis (+) Hyptis (-) A. lebbeck A. procera T. grandis D. strictus * A. indica D. sissoo P. pinnata S. robusta Mono-culture (exotic) A. auriculiformis C. equisetifolia E. hybrid G. pteridifolia Mixed-culture A. lebbeck + A. catechu A. indica + P. emblica D. sissoo + T. grandis D. strictus + T. grandis

29 Tree layer Net Production (t ha -1 yr -1 ) Stem Net Production (t ha -1 yr -1 ) Relationships between tree layer net production and stem net production with leaf biomass for all exotic (a, b) and all native woody species (c, d) All exotic species Y= X r=0.9156, p<0.001 a All native species Y= X r=0.952, p< Y= X r=0.5495, p<0.1 b c Y= X r=0.913, p<0.001 d NPP is a direct function of the amount of foliage biomass. Foliage is an important component of the plant for functional aspect. Dry matter of the foliage is the litter fall. Litter fall is the nutrient currency of the plants which generate more microbial diversity in the soil used to generate more microbial biomass carbon Leaf biomass (t ha -1 ) Leaf biomass (t ha -1 ) (Source: Singh, Communicated in Land Degradation and Development) 29

30 Relationships between microbial biomass C with soil organic C and microbial biomass C with litter fall for all exotic (a, b) and all native woody species (c, d). Microbial C (µg g -1 ) All exotic species Y=101.64e X r=0.5168, p< Soil C (%) All native species Y= e 0.911X r=0.852, p< Soil C (%) Nonlinear positive relationship between SOC and microbial biomass C indicates both parameters mirror each other. Litter fall is the substrate supply for microbial population that regulate organic matter and mineralization rate in early phase of soil redevelopment. Microbial C (µg g-1) 200 Y= e X r= , p< Y= X r=0.917, p<0.001 Organic matter play a major role in determining the structure and functioning of an ecosystem Litter fall (t ha -1 ) Litter fall (t ha-1) (Source: Singh, Communicated in Land Degradation and Development) 30

31 Tree layer Net Production (t ha -1 yr -1 ) Stem Net Production (t ha -1 yr -1 ) Relationships between tree layer net production and stem net production with N-mineralization rates for all exotic (a, b) and all native woody species (c, d) All exotic species Y= lnX r=0.0673, p<0.1 a All native species Y= lnX r=0.649, p< Y= lnX r=0.0960, p<0.1 b c Y= lnX r=0.815, p<0.01 d The rate of N- mineralization has been considered the rate of nutrient availability or nutrient supply. This relationship indicated NPP is a function of nutrient availability and is limited by it. As more and N becomes available, the plant will be able to withdraw more and more N from soil. N-mineralization rate is the functional indexes of soil redevelopment N-mineralization (µg g -1 mo -1 ) N-mineralization (µg g -1 mo -1 ) (Source: Singh, Communicated 31 in Land Degradation and Development)

32 Conclusions: Biomass and net primary production values were substantially better in the native species while growth performance exhibited more or less similar with exotic plantations but varied between species. Microbial biomass C, N, P and N-mineralization rates were significantly higher in the native plantations from exotic species. Redevelopment of soil biological fertility on mine spoil was strongly integrated with native species as compared to the exotic which confirms the better efficiency of restoration potential for restoring degraded ecosystem at least from stage. 32 In conclusion, plantations of exotic species, either legume or non-leguminous, are not as effective in mine spoil rehabilitation as those of native species do. But entry of invasive species in the plantation plots of native as well as exotic woody species is affecting mechanism of restoration. So, how to proceed ?

33 Conclusion: Human Environment Development 33!!Biodiversity? Sustainable Development???? Consider human demands + biodiversity priorities at terrestrial landscapes

34 Many THANKS for your kind attention! 34