Source: HMGN-DFRS (1999)
Forests are also under increasing pressure from growing human populations and their demands for fuelwood, timber, leaf litter, and other forest products, the impacts of excessive numbers of livestock, and the construction of roads, dams, settlements, etc. When the continued removal of forest products exceeds the capacity of the forest to regenerate, degradation ensues. If unchecked, this process will turn forests into wastelands. Deforestation and forest degradation have already reduced the availability of timber, fuelwood, leaf litter, fodder, and forage. This has depressed rural incomes and contributed to soil erosion and loss of soil fertility, damaged ecosystems, and degraded catchments.
It has been estimated that an annual loss of Rupees 11.55 billion occurs as a result of deforestation (Table 4.4).
Table 4.4 Estimated annual financial losses (in Nepali Rupees – Rs.) due to deforestation
Source: Kanel (2000, unpublished)
The Government of Nepal is gradually handing over management of forests back to villagers, who largely depend on forest products for their survival. Progress is slow, not just because trees take time to grow, but also because attitudes are slow to change (Sattaur 1987). Contrary to general belief, deforestation of Nepal’s Mid-hills of is not a recent occurrence, and deforestation was well underway in the region by the late 18th century (Sattaur 1987).
Pine was the most widely planted species in the Mid-hills. Unfortunately, pine is of little value to farmers. It is useful as construction timber, but timber only ranks fourth on a farmer’s priority list. Fodder and bedding material for livestock and fuel are what the people need most (Sattaur 1987). Any attempt to remove the threat of deforestation through reforestation must be based on reliable data, including what tree species are most useful for the local population.
Threats to rangeland biodiversity There are enormous pressures on rangeland ecosystems. According to some estimates, there are nine times more grazing animals than the land can viably support. This high grazing pressure depletes palatable plant species, especially legumes. With its extremes of wind, rainfall, and temperature, arid mountain rangeland is especially prone to the process of desiccation that can be caused or accelerated by overgrazing.
Most rangeland ecosystems located in arid regions and high mountain pastures are relatively susceptible to degradation because they are less resilient to disruptions than subtropical ecosystems. Moderately degraded rangelands can usually be restored over time through integrated management systems. Severely degraded rangelands may require both investment and improved techniques to make them economically viable and ecologically restored.
Threats to protected areas There are many conflicts and threats that affect the entire Protected Areas System in Nepal. A few examples are discussed below:
Grazing is a year-round threat to many of the protected areas in the Terai, whereas it is usually only a seasonal threat to the high elevation pastures of the Himalayas. In either case, overgrazing is prevalent. The level of livestock grazing is also one of the most serious threats to the ecological integrity of the Mid-hill and highland PAs. Management responsibility for the northern rangelands is unclear.
Poaching for high value products for international markets, such as musk glands from musk deer, is fundamentally different in scope and in degree from the occasional poaching of wild animals to supplement rural diets. The former is considered a much greater threat and a higher priority for action. In spite of a number of measures taken to prevent poaching of wildlife, frequent reports are published of poachers caught in possession of wildlife parts. The main species poached in the Terai are the Royal Bengal tiger and the one-horned rhinoceros, and musk deer in the high mountain.
Illegal timber harvesting of commercial tree species is a constant threat. Tourism in and around PAs continues to develop in a haphazard and ad hoc manner. Uncoordinated private sector initiatives have enabled outsiders (non-Nepalese) to reap substantial benefits from tourism with very little benefit trickling down to the local communities. The PAs have been increasingly threatened by infrastructure development projects such as roads, irrigation canals, and hydroelectric dams. Land dedicated to PAs can no longer remain pristine if the surrounding areas are not suitably developed with proactive planning. Although environmental impact assessments are mandatory, a few industries discharging harmful effluents are built too close to PAs. Established industries with their increasing production capacities are unrestrained and continue to pollute river systems running through parks.
Other issues transcend technical government offices and are perhaps most difficult to solve. Political influences are strong and people in power have many means at their disposal to circumvent rules and regulations, in this case, the National Parks and Wildlife Conservation Act. If anything, political powers and influences have increased since the start of the modern multiparty political era in 1990, and park or reserve managers are powerless to stop certain excesses and are forced to turn a blind eye to irregularities. Such cases have become increasingly harder to control and are virtually impossible to prosecute.
Habitat degradation also occurs as a result of inadequate management of protected areas and their buffer zones. Management capacity and expertise is limited, and while management staffs of PAs are enthusiastic and committed, they lack the training and resources to do a proper job. They also lack operational plans to guide them in their management activities.
Threats to wetland biodiversity Wetland biodiversity is under threat from encroachment of wetland habitat, unsustainable harvesting of wetland resources, industrial pollution, agricultural runoff, siltation, and the introduction of exotic and invasive species into wetland ecosystems.
Encroachment on wetlands is primarily due to: (i) drainage for irrigation, reclamation, and fishing; (ii) filling in for solid waste disposal, road construction and commercial, residential, and industrial development; (iii) conversion of sites for aquaculture; (iv) construction of dams, barrages, and other barriers for controlling water flow; (v) groundwater extraction using high powered pumps, and digging ditches in sites where there is no inflow of water; (vi) discharge of sediments and pollutants from nearby areas; (vii) grazing; and (viii) removal of soil from the site.
This encroachment has resulted in a number of negative impacts, including reduction of wetland areas, deposition of silt and sediment, and eutrophication caused by agricultural runoff and/or industrial effluents.
Unsustainable practices include over fishing and the indiscriminate use of poison and dynamite to kill fish. The introduction of exotic fish species has also been recognised as a possible threat to native species. Poaching is a major threat to crocodiles, particularly the gharial and mugger crocodiles found in the Kali Gandaki River and in the major tributaries of the Narayani River.
The number of fish species in the Bagmati River has declined from 54 to 7 within a decade as a result of the inflow of industrial sewage. The high concentration of organic matter and chemicals in effluents has killed fish and destroyed the plant life they depend on (Shrestha et al. 1979; Sharma & Pantha 1992).
Empirical evidence collected from a rapid reconnaissance survey of 163 wetland sites and their resources revealed that the wetlands of the Terai are vulnerable to many threats, including the proliferation of exotic species. Eichhornia crassipes (water hyacinth) threatens the survival of several wetland ecosystems in the Terai, as it forms a dense mat blocking sunlight penetration under water and ultimately changing the chemistry of the water (IUCN-Nepal 1996).
About 66% of the wetlands of the hills and mountains are threatened by siltation. A further 62% show problems due to agricultural runoff. In addition to agricultural runoff, they also suffer from factory effluents, washing and sewage emissions, and domestic effluents. Finally, dredging and drainage threaten almost two-thirds of these wetlands.
Threats to mountain biodiversity Poverty, ecological fragility, and instability of high mountain environments, deforestation, poor management of natural resources, and inappropriate farming practices are the primary threats to mountain biodiversity. The cumulative impacts of these threats result in accelerated soil erosion, catchment degradation, and loss of biodiversity.
One of the greatest threats facing Himalayan flora and fauna is over-exploitation and poaching for trade. Of the many species threatened with extinction, three wildlife species (Himalayan black bear, Selenarctos thibetanus, Brown bear, Ursus arctos,and the Himalayan musk deer, Moschus chrysogster) are poached for certain organs that fetch enormous amounts of money through illegal international trade. It has been estimated that for every male deer that yields one musk pod, four deer are killed.
Mountain communities often suffer from economic and legal marginalisation due to low soil fertility, small plots of arable land, climatic vagaries, and higher caloric requirements related to the lower oxygen content in the air. Access to the benefits available to other segments of society are also often curtailed and limited because of their location far from the seats of power in the capital. Mountain communities rely on small-scale production systems resulting in higher production costs.
22.214.171.124 The threat of species loss
Over-exploitation of biological resources The natural and semi-natural forest habitats are mostly distributed in two management systems - protected areas and national forests. Approximately 70% of the forests of the Terai–Siwalik Hills zone are national forests and the rest are within protected areas (Joshi et al. 1996b). The Mid-hills forest ecosystems are inadequately represented in protected areas and are considered threatened. Forest habitats outside the PAs include a number of forest types under the jurisdiction of the Department of Forests. However, these habitats are rapidly degrading due to over-exploitation.
Felling of Sal (Shorea robusta), Khair (Acacia catechu), Simal (Bombax ceiba), Satisal (Dalbergia latifolia), and Bijaysal (Pterocarpus marsupium) in the Terai, collection of biomass such as leaf litter, fodder, and fuelwood in the hills, collection of Lokta and medicinal and aromatic plants, heavy lopping of oak trees for fodder, and cutting of blue pine trees in high altitude forests for roof shingles and timber for house construction all have negative impacts on forest biodiversity in these regions. It is widely believed that harvesting of medicinal plants is no longer sustainable in many areas.
A majority of Nepalese people depend largely on forest resources for their subsistence. They use forest products for fuel materials, timber, shelter, medicine, food, and fodder. Over 75% of the energy resources and over 40% of fodder needs are met through forest resources (HMGN/ADB/FINNIDA 1988). A threat to these biological resources is also a threat to the social and economic well being of these people.
Threats to forest biodiversity Despite the conservation benefit provided by the PAs network, biodiversity loss in Nepal continues unabated. The most critical threat to biodiversity is habitat destruction. The Nepal Conservation Strategy raised the alarm that if Nepal were to lose its remaining humid tropical forests, an estimated ten species of highly valuable timber trees, six species of fibre trees, six species of edible fruit trees, four species of medicinal herbs and fifty species of other trees and shrubs would be lost forever. In addition, the habitats for 200 species of birds, ten species of mammals and twenty species of reptiles and amphibians would be severely affected. Shrestha et al. (1998) reported that 68% of plant species were lost when 41% of the density and 50% of the tree biomass were lost in Riyale, Kabhrepalanchowk. Similarly, Shrestha et al. (2000) reported that a 78.2% plant species loss occurred when 83.1% of the density and 80.1% of the tree biomass were lost in the degraded forests of Chitrepani, Makwanpur district, as compared to natural forests.
Threats to endangered plants and animals are increasing due to the high commercial values in local and international markets for specific plants and animal parts. In Nepal, 56 mammal, 226 bird, 25 reptile, nine amphibian, 35 fish, and 142 butterfly species are threatened with extinction locally.
Threats to Non-Timber Forest Products (NTFPs) The most critical threats to all NTFPs are deforestation, habitat degradation, and unsustainable harvesting. The most common NTFPs that are traded on a large scale (over 100 tonnes/year) are Pine resin (khoto), Sal seed, Kutch, Ritha, Timur, Dalchini and Tejpat, Sabai grass (or Babiyo), Lokta, Satawari (or Kurilo), Chirayito, Jatamansi, Padamchal, and Sugandhkokila (Malla et al. 1993).
The collection and trade of these valuable natural resources has generated considerable employment opportunities in remote areas where the majority of people are poor. Trade in NTFPs and medicinal plants is the basis of the livelihoods of a large number of rural people, and their collection is likely to continue for a long time to come. However, their collection is unregulated and indiscriminate. Unsustainable harvesting has reduced the quantity and quality of many NTFPs in the wild. However, despite considerable anecdotal evidence suggesting that over-harvesting of medicinal plants is occurring, quantitative data are lacking. Without such data, it is impossible to analyse and assess the effects of harvesting on plant populations in natural communities or to design appropriate conservation and management plans.
126.96.36.199 The threat of loss of agrobiodiversity and genetic resources
The genetic resources of Nepal are in a state of depletion. This is primarily due to the destruction of natural habitat, over-grazing, land fragmentation, commercialisation of agriculture and the extension of high-yielding crop varieties, indiscriminate use of pesticides, population growth and urbanisation, changes in farmers’ priorities, and lack of awareness among policy makers and planners about the importance of agrobiodiversity.
Rice landraces are being replaced or discontinued through the introduction of modern varieties that have high yield potential (Rijal et al. 1997). Key reasons for the erosion of rice landraces are: (i) changes in suitable habitats; (ii) under-valuing of landraces and no institutional support for their conservation; (iii) government policy of extending modern varieties for increasing total biological return; (iv) lack of promotional activities for landraces; and (v) failure of research systems to improve upon the existing landraces. Nepal’s traditional agroecosystems and the agrobiodiversity found within them are also threatened by agricultural policies that favour centralised control and subsidies for high-input agriculture. The Ninth Five-Year Plan (1997-2002) has identified the need for sustainable agricultural development without jeopardising the natural environment.
As with crop diversity, the biggest threat to livestock diversity is the decline and degradation of traditional farming systems. Under current policies and economic pressures, it is impossible for ordinary farmers to conserve or preserve traditional breeds, strains, and populations of domesticated animals.