The land is always spatially heterogeneous (an uneven, non-random distribution of objects), that always has structure. The key is solar energy. Over geologic time it produces landforms, and today it grows different plants, which provide structure or heterogeneity to the land.
Three mechanisms create Mosaic pattern
Substrate Heterogeneity – hills, wet spots and different soil types, causes vegetation patchiness.
Natural Disturbance – fire, heavy rains, pest explosions etc.
Human Activity – Plowing Fields, cutting woodlots, building roads, creating patches, corridors, boundaries.
Various biological processes commonly modify and enhance the pattern .
The chemical elements, including all the essential elements of protoplasm, tend to circulate in the biosphere in characteristic paths from environment to organisms and back to the environment. These more or less circular paths are known as biogeochemical cycles.
The movement of those elements and inorganic compounds that are essential to life can be conveniently designated as nutrient cycling.
Example – Nitrogen cycle, Phosphorous cycle, Sulfur cycle etc.
The rate of release of nutrients from the solids, the solar input and the cycle of temperature, day length and other climatic conditions are the most important processes, which daily regulate the rate of function entire ecosystem.
Four Ecosystem processes :
Water cycle, Mineral cycle, Energy flow, Community dynamics (also called succession).
Modifying any one of these processes automatically changes all of them because in reality, they are only different aspects of the same thing.
Natures services which are essential for human life, are generated by a complex of natural cycles driven by solar energy, that constitute the workings of the biosphere, the thin layer near earth’s surface that contains all known life.
Following are few important natural services
Purification of air & water
Mitigation of floods & droughts
Detoxification & decomposition of wastes
Generation & renewal of soil & soil fertility
Pollination of crops & natural vegetation
Control of vast majority of potential agricultural pests
Dispersal of seeds and translocation of nutrients
Maintenance of biodiversity, from which humanity has derived key elements of its agricultural, medicinal & industrial enterprise
Maintaining the global atmosphere, regulating the earth’s weather patterns
India covers about 2% the land area of the world but possesses more than 8% of world’s Bio-Diversity. High endemism is the character of the Indian Biodiversity. Hence Biodiversity loss is irreversible.
As explained earlier together with physical conditions, biodiversity also helps to define characters of nature’s services . If an area atmosphere, soil and water are polluted, nature’s services will be affected. The existing biodiversity will be an indicator of disturbed condition.
The variety of species provides a gigantic gene bank which becomes an unlimited source of food & fiber, medicines, antibiotics, pesticides and raw materials for different industries.
Wild genes are much stronger in resisting diseases and can impart this strength to domesticated plants such as crops to make them pest resistant.
For Biodiversity it is not only the number and variety of species and sub-species of plants and animals, higher and lower but also, includes the variety of habitats & niches available in particular area. Habitat is the address & niches available is the profession of each species.
It is extremely difficult to separate out and count each and every habitat and niche as they are connected to each other & to larger divisions like biomes in a maze of linkages.
Hence conservation of Biodiversity through protection and elimination of human impacts, which means a kind of relapse into conditions that existed sometimes in the past. The same can be called Restoration of natural processes.
The study of the patterns of distribution of organisms in space and time is called biogeography.
India – A Tropical Country
Characteristics of the Tropics
Acute Water Shortage
Fragile Soils – poor moisture retention and organic content
High Evaporation Rate
High Decomposition Rate
Bio-Geographic zones of Maharashtra – A case study I Konkan – Narrow strip between Arabian Sea and Western Ghats (Sahyadri), II Crestline of Western Ghats (Sahyadri), III Slopes, IV Dry Deciduous Zone of Marathwada and Khandesh, V Dry evergreen Zone of Vidarbha
Areas of natural vegetation, such as forests or grasslands, have distinctive climate, which is a modification of the general climate typical of the geographical region in which they are situated. These modifications are the result both of small-scale geographical variation in terrain—slope, aspect, etc. – and of the shading and deflection of wind and rain by the community itself. Such local climates are called Microclimates.
Important factors in development of Microclimates are the extent of penetration into the vegetation of sunlight energy, of heat, and of wind and rain (which cause cooling and control humidity).
Few illustrations South facing slopes in Northern Hemisphere receive more sun than north facing ones, for instance, and thus are warmer and tend to be drier. They are also often more sheltered from the cold North-East winds, and these factors influence the biotic community that develops on them. The vegetation itself greatly influences the climate and community. Tall plants, for instance, provide smaller members of the community with shade and protection from wind and rain. The Microclimate of grassland is very much influenced by the height and density of the vegetation. When the height of the vegetation varies in different seasons, the microhabitats will also vary. The activities of herbivorous insects such as caterpillars, grasshoppers are very much influenced by the conditions of humidity and temperature among the grasses on which they feed.
Trenches on slopes will accelerate erosion sources from internet
Soil Conservation- Ecological Point of View Every landscape has variety of vegetation cover spread all over the landscape through variety of land features right from upper reaches to bottom of any slope for example some where depressions, some where steep and medium slopes, rocky out crops etc. These cover types have a specific character and role to play with that land feature for example reducing erosion, absorbing rain shocks etc. . Shola Forests in ravines
Objectives Maintain an association between different land features and their vegetation cover over the landscape , so as to maintain the biological and physical processes (erosion etc.) over the landscape. Significance Contour trenches or benches as a generalized and uniform approach all over the slopes from top to bottom is ecologically incorrect and consideration of physical as well as biological processes according to land classes is important
Ecological Point of View – Ridge to Valley through Stream and Cover Types
Stream plays an important role of connection between Ridge and Valley.
Stream processes that create habitats, integrate the physical and biological processes across watershed.
Cover types over different land classes plays important role in maintaining physical and biological processes.
Stream restoration is the re-establishment of the general structure, functions and self-sustaining behavior of the stream system that existed prior to disturbance.
It is a holistic process that requires an understanding of all physical and biological components of the stream system and its watershed.
Temporary Half moon shaped pool where flow is retained for a while Restoration includes a broad range of measures, including the removal of the watershed disturbances that are causing stream instability; installation of structures and planting of vegetation to protect streambanks and provide habitat; and then reshaping or replacement of unstable stream reaches into appropriately designed functional streams and associated floodplains.
Ecological Surveys, Restoration Measures and Monitoring in three important areas of stream ecosystem i.e. watershed, stream channel and riparian vegetation.
Surveys are carried out to understand present conditions of stream (stable or unstable) by assessing physical and biological components of stream in above mentioned areas.
Riparian Vegetation in good condition on one bank and disturbed on other bank Survey of Riparian Vegetation A survey of riparian vegetation is carried out to study condition of present vegetation over there, its association with the aquatic as well as terrestrial fauna over there. For example it can serve as a breeding habitat, feeding habitat or corridors for all types of faunas etc.
Study of variety of vegetation cover spread all over the watershed, through variety of land features right from upper reaches to bottom of any slope, some where depressions, some where steep and medium slopes, rocky out crops, wetlands etc.
Survey of Stream Channel
This survey is done in three reaches particularly upper (high slope), middle (medium slope), lower (plains)
Highly Eroded Stream Banks Purpose: To assess condition of Stream banks, check whether erosion is taking place and if yes at what rate. To assess condition of stream channel, check whether degradation or aggradations is taking place. To assess human Interferences on stream channel like dams, instream cultivation, degradation or aggradations, use of stream as for waste disposal, pathways for livestock etc.
Identifying anchoring places and introducing native species
Creating and Maintaining Natural Cover Type over Gullies and Ravines, which plays important role of moisture retention and corridors for fauna.
Building Half Moon Shaped Pools In Stream Channel For Bank and Channel Protection from erosion: Root wads, Rock Vanes (Single, Cross, J-shaped vanes), Point Bars, Rip-Rap etc. For Habitats creation and Pathways for aquatic fauna: Half moon shaped pools, fish ladders.
Tall Trees obstruct the wind movement which results into lesser evaporation loss of nearby water bodies. Tall Trees are also responsible for rains.
Presence of good Riparian vegetation results into cooling of water in stream reducing evaporation loss. In Dry season leaf litter of these trees fallen into the stream channel also results into reducing the evaporation loss through soil.
Riparian Vegetation Few Cover Types and their Ecological roles Shrubs – Faunal diversity Insects Shrubs provide habitats for lesser fauna like insects etc. Clusters – Gene bank Clusters as an association of shrubs, herbs, tall trees, climbers serve as a gene bank over any landscape.