You are right Dr Deka. I still remember , in notheastern region , considered to be the natural home of so many citrus species , many of them now no longer visible in the region .The prime region for such irrpairable loss in diversity  is simply the loss of  natural habitat for those species. And loss of those natural habitat comes through soil environment . The citrus specie slike Citrus indica , citrus megalaxycarpa, Citrus ichagenesis etc are not easily identifiable . Shifting cultivation by cutting forest alnd followed by slash and burn , really triggered the that site  for many plant species  .  

Yes, in North Eastern India loss of soil site characteristics is major reason for biodiversity loss. Deforestation is attributed for such loss.

You are right Dr Deka. I still remember , in notheastern region , considered to be the natural home of so many citrus species , many of them now no longer visible in the region .The prime region for such irrpairable loss in diversity  is simply the loss of  natural habitat for those species. And loss of those natural habitat comes through soil environment . The citrus specie slike Citrus indica , citrus megalaxycarpa, Citrus ichagenesis etc are not easily identifiable . Shifting cultivation by cutting forest alnd followed by slash and burn , really triggered the that site  for many plant species  .  

Let me share with you another good piece of information , stating temperature driven shifts in soil microbial community composition are not soil dependent ?. What is your opinion friends ?.

It is again a very good question . My all colleagues will

agree with me that there are some phenomenal changes in soil

environment taking place, both temporally and spatially . Both the

types of changes are surely responsible for plant diversity loss.

Thanks Abhishek for excellent PDFs  and equally suitable links , i urge upon my friends  who are the part of the discussion , kindly go through these PDFs and links , so informative indeed. 

yes Mr Anoop disturbance in soil environment is one of the causes of plant diversity loss.In Iraq we are suffering from increasing of salt affected soils areas due to bad drainage which affect  soil characters ,microorganisms diversity , as aresult   it cause a plant diversity loss,and the dominant of new plant species with less economical value.

Thanks Dr Ali for your response. Thats the prime reason , especially in Saharan and sub-saharan regions , shifting cultivation has damaged the plant diversity as well as soil microbial diversity to irreversibility. 

Dr Anoop, thanks for bringing up yet another important issue. In some of the comments the discussions are covered for change in biodiversity as a whole instead of plant diversity. Definitely soil disturbance is a major cause for changing plant diversity. While concluding the discussion we should make it for both frequency and intensity of soil disturbance. Besides, is it so that microbial communities do not show similar change to soil disturbance as that by plant species? 

Disturbances of soil could be done in different ways: removal of top soil, erosion, intensive cultivation, industrial wastes deposition, slash and burning, etc etc. All these influence plant communities along with soil biota. If dispersal of plans are disturbed by any means severely, disappearance of a particular species can take place.

Soil environment is equally responsible for microbial diversity. Do you feel, plant diversity and microbial diversity are inter-related?

This is not my field of specialty, but it is undeniable the existence of an empirically sustainable relationship between human action in certain environments and loss of biodiversity in them, which is reinforced by climate change that acts on a global scale, not requiring that its effects are perceived only where there is a direct human action.

Abdul Ghafoor to you1 day ago

Dear Dr Anoop Kumar Srivastava

YOu are very coorect in saying "Many factors could be accounted for such precious loss in diversity . If climate change is accountable , there are certain changes in soil environment as well".

You know that the "Flower Diagram" of Jenny for pedo-genesis of soils. From it I understand that the soil properties are controlled by the environmental factors as well. And the concurrent climate does change the efficiency of these factors and hence changes in soil properties has to be a natural consequence.

Every plant has it own agro-climatic condition, changes in which generally damage the plant bio-diversity. In addition the anthropological activities, at local level, are also degrading the bio-diversity and we are witnessing it daily in our life. Hence I could conclude the climate change is one factor for decreasing biodiversity, i.e. plants, microbes, cattle, and even the morphology of human being. Keep in mind that I am not ecologist and this is just layman description.

Dr. Meena Potdar to you2 days ago

yes i agree

Sir, yes off-course. Some halophytes disappeared after amendment of salt affected soil. Certain plants are indicator of zinc other nutrients abundance and are scanty when their availability reduces or loss by run-off. Some plant flourish with poor nutrient and water supply and in contrast to it poor growth and snuff-out with abundance. High temperature and salinity along with moisture stress is desirable for Halotropium. Recently I have presented such plant species during 3rd IUPAC Conference in April at New Delhi. There are n number of factors are responsible for loss of biodiversity among them soil is one and its conditions.

Thanks and regards 

Thanks Dr Aiswath for valuable feedback . I am in total agreement with you . Unfortunately , soil site environment redressal is never attempted during any biodiversity exploration . Loss of biodiversity is nothing but loss of natural habitat  ( especially the mcrobial environment ) for a given plant species  

Dr Aiswath, this is the reason soil condition is very often an indicator of habitat for certain plant type.

Yes i agree with you Dr Deka. Seed spices themselves come up excellently in salt affected soils . Likewise coconut comes so well in coastal soils ..? You can cite so many examples . Hope , Dr Aiswath wil agree. 

Abhishek , your ability is outstanding . Lets share this piece of information with our colleagues:

Plant indicators for agriculture: Many plant indicators decide whether soil is suitable for agriculture or not. The growth of a particular crop plant is seen under different environmental conditions and if growth is satisfactory in a particular soil that soil is considered to be suitable for agriculture. For example, growth of the short grasses indicates that water is less in the soil. A natural growth of tall and short grasses indicates that soil is fertile and is also suitable for agriculture. 

 Plant indicators for groundwater:Certain plant communities indicate the depth of ground water. Central Arid Zone Research Institute, Jodhpur has made the use of certain plant communities to indicate the depth of groundwater and salinity level in the groundwater. 

 Plant indicators for Over-grazing:Many plants are over grazed which result in modification of grassland. It has been seen that grasses are removed by overgrazing while others are disturbed and forage production is considerably reduced. Some plants which are vigorous and undisturbed, remain viable and become distinct from rest of the plants.

Some plants show characteristic indication of overgrazing which can be recognized. The predominance of annual weeds and short-lived impala-table perennials indicate severe grazing. Examples of such plants are Polygonum, Chenopodium, Lepidium and Verbena. Some plants are less pronounced and show poor or no over-grazing. Examples of these plants are Opuntia, Grindelia, Vernonia etc.

Plant indicators of forest:Some plants indicate the characteristic types of forest and they grow in an area which is not disturbed. Narenga porphyrocoma is a grass which binds the soil. In such a soil sal (Shorea robustd) can be cultivated. Viola species in western Himalayas is a suitable indicator for plantation of Cedrus deodara and Pinus wallichiana. If we know that a particular forest grows better in certain area of specific soil the productivity can be increased. For example, Quercus stellata and Q. mariandica grow on upland, lowland or on sterile sandy soils.

Sometimes forests is destroyed due to fire, overgrazing and other environmental factors and the area is left to reach upto climax. In this, subdominant species get favourable chances for growth and survival. This indicates the future plants to come and establish.

Plant indicators for humus:Some plants act as humus indicators. Monotropa, Neottia and mushrooms indicate the presence of humus in soil. Strobilanthes and Impatiens indicate the presence of high humus or litter which prevents regeneration of tree species.

Plant indicators for moisture:Plants which prefer to grow in arid area indicate the poor or very low moisture content in the soil. Sacchamm munja, Acacia nilotica, Calotropis, Agave, Opuntia, Argemone are such plants. Some plants grow in low soil moisture as Citrullus colocynthis. Eucalyptus lowers the water table. Echinops echinatus. Cassia auriculata are found in the area of deep water table. Typha, Phragmites, and Vetiveria grow in water-logged soil. Growth of Typha, Phragmites, Juncus and Carex indicates the swampy condition. Mangrove vegetation and Polygonum are found in water-logged saline soils.

Plant indicators for Soil types:Many plants indicate the characteristic soils. For example, Casuarina equisetifolia, Ipomoea pes-caprae, Citrullus colocynthis, Calligonum polygonoides, Lycium barbarum and Panicum grow in sandy soil. Sacchamm munja prefers to grow in sandy loams. Imperata cylindrica and Vetiveria zizanioides grow on clayey soils. Cotton prefers to grow in black soil.

Plants indicators for soil reaction:Many plants indicate whether the soil is acidic or basic. For example, Rumex acetosa. Rhododendron, Polytrichum and Sphagnum indicate acidic soils. Many forest trees as Shorea robusta, Pinus roxburghii are calcium loving. Tectona grandis (teak), Cupressus torulosa, Ixora parviflora and Taxus baccata are calcicoles. Some mosses e.g. Tartulla and Neckera grow on lime stones. Halophytes such as Suaeda fruticosa, Tamarix ariculata, Salicornea, Chenopodium, Salsola foetida grow in salty soil.

Excellent piece of information  as a further supplement to on-going discussion . Keep it up Abhishek..

prof in my view soil environment disturbance is the main reason of plant diversity. the responsible factors may include soil erosion, acid rain, floods to name a few. similarly plants will slowly go through the natural selection procedures and specific diversity will be obtained.

Thanks Hussain . The second part of your respond , i find more interesting . Under a renewed soil conditions , the , there is reorientation , natural selection and re-establishment of diversity to stabilize the  ecosystem with time... Good response. 

Plant diversity reduction could be caused by many factors. If the soil condition is changed by manual factors or natural disasters,these might lead to  high salt content or less nutrient can not  meet the need for plant growth. Sometimes  the bacterials will be affected directly with a soil change, and then have a effect on those plants with a symbiosis relation of microorganism.  

Yes i do agree with you Xiaohui. Soil is such a live material that its sensitivity is often judged by the gradual loss in natural habitat .And , most of the times , such habitat loss goes un-noticed to custodial of that farm land .  It comes to ones notice only when , land under-performs consistently . The prime reason for such paradigm shift in crop performance is nothing , but the diversity loss of   invisible managers of soil fertility , thesoil microbial diversity..?

Very interesting feedback Abhishek . It will be  more worthwhile to investigate the preponderance of one microbial community over other(s) with change in soil environment or ecosystem settings. And if that happens , the ecosystem services and trade offs will undergo  a huge reorientation, structurally as well as metabolically . It is often claimed a characteristic microbial diversity associated with a agroecosystem , sustained over the years under a set agricultural practices , how long biologically it sustains , is a matter of  great interest . Hope , we will get further debate on this issue. 

Endorsing all excellent contributions by Abhishek , let me add some more information .   Our major constraint  is the mere 1% of microbial diversity  is identified as cultured microbes and rest of 99% microbial diversity is still un-characterized . however , introduction of molecular tools have made it possible to link microbial taxonomy with functional taxonomy. the attempts such as these have , infact , opened up the Black box of the microbial diversity.

The global decline in biodiversity has generated concern over the consequences for ecosystem functioning and services. Although ecosystem functions driven by soil microorganisms such as plant productivity, decomposition, and nutrient cycling are of particular importance, interrelationships between plant diversity and soil microorganisms are poorly understood. Tthe response of soil microorganisms to variations in plant species richness (1–60) and plant functional group richness (1–4) in an experimental grassland system over a period of six years. Major abiotic and biotic factors were considered for exploring the mechanisms responsible for diversity effects. Further, microbial growth characteristics were assessed following the addition of macronutrients. Effects of plant diversity on soil microorganisms were most pronounced in the most diverse plant communities though differences only became established after a time lag of four years. Differences in microbial growth characteristics indicate successional changes from a disturbed  zymogeneous) to an established (autochthonous) microbial community four years after establishment of the experiment. Supporting the singular hypothesis for plant diversity, the results suggest that plant species are unique, each contributing to the functioning of the belowground system. The results reinforce the need for long-term biodiversity experiments to fully ppreciate consequences of current biodiversity loss for ecosystem functioning.( Source : Eisenhauer et al. 2010. Ecology 9: 485-496)

Some  of the plant performs best in specific type of soil, and also prefer the respective type of soil.In such case of there is any disturbance in soil , it may hamper the life, condition of plant resulting loss in diversity of plant.

Loss of habitat for a plant species is considered as a major setback for microbial density to deplete gradually with time , which could be triggered by changes in management practices or climate change related issues..

Human activities to improve productivity of specific crops using different means of fertilizing (chemical, organic , or bio fertilizer )could affect soil microorganisms diversity ,nutrients availability (quantity and quality),soil pH. This means we are face a new soil environment suitable for specific types of plants but not others .In other word this new environment of the soil caused loss of habitat for a plant species  .

I agree with  you  Dr Ali . Your statements are correct , this is what has happend ..