4. Threats to tropical forests

badgers, bobcats, and mountain lions), birds (crested guan, magpie jay, hawks, and bull

These forests occur in humid climate region at Nearctic and Neotropical Ecozones from Mid-Atlantic states to Nicaragua, the Greater Antilles, Bahamas, and Bermuda [16]. They are characterized by diverse coniferous species whose needles have adjusted to deal with low precipitation (around 2.4<sup>00</sup> or 60 mm) and moderate temperature (18 or 64�C or higher). These forests are dominated by Pinus caribaea, P. tropicalis, P. chiapensis, P. tecunumanii, P. ayacahuite, P. maximin, Byrsonima crassifolia, Colpothrinax wrightii, Chrysobalanus icaco, Quercus cubana, Calophyllum pinetorum, Erythroxylum minutifolium, Phania cajalbanica, Vaccinium cubense, Hyperbaena columbica, Clusia rosea, Aristida spp., Andropogon spp., Quercus corrugata, Q. skinneri, Q. oleoides, Q. candicans, Q. acatenangensi, Q. brachystachys, Q. peduncularis, Q. polymorpha, and Q. conspersa. The crown canopy is close and thick, the understory is rich in shrubs and small trees, while the ground is dominantly covered with ferns and grasses. These forests has harbored wide array of mammals (such as Cervus unicolor, Muntiacus muntjak, Sus scrofa, Selenarctos thibetanus, Capricornis sumatraensis, Rafuta spp.) and bird species (i.e., Polyplectron chalcurum, Pericrocotus miniatus, Chloropsis venusta, Myophonus melanurus, Niltava sumatrana, Cinclidium diana, Pycnonotus leucogrammicus, P. tympanistrigus, Hypsipetes virescens, Zosterops

Tropical forests provide diverse ecosystem services, such as play major role in water cycle, that is, they return around 90.0% precipitation into the atmosphere in the form of water vapors, increase the life span of dams through reducing the sediments into rivers, mitigate the disasters through reducing soil erosion and land sliding, and reduce the intensity and severity of floods [17]. Tropical forests are vital important for human well-being, that is, they contribute major proportion in food security (i.e., around global crops and one-third food supply depend on wild pollinators), regulate weather condition, reduce the negative effects of climate change by acting pollution filters, and serve as storage biodiversity. It has been stated that tropical forest may harbor >50.0% of world's terrestrial animal species [18]. Tropical forests play a crucial role in climate change, that is, the vegetation of tropical forest stored a huge amount of carbon taking from the atmosphere and stored in their various parts of the body (i.e., in leaves, stems, and roots, etc.) and serves as mega carbon storehouse or sinks (e.g., 25% store of world's carbon). It has been known that tropical forest can store huge amount of carbon compared to those they release back into atmosphere, slow down the rate of carbon dioxide accumulation in the atmosphere, and reduce the effect of climate change. Hence, this indicated that tropical forests play a significant role to reduce the effects of climate change and reduce 12% emission of greenhouse gases into the atmosphere. Wildlife species are the essential component of the tropical forest ecosystem, that is, they play a major role, that is, pest control, pollination, and seed dispersal in tropical forest ecosystem [19]. At habitat level, the occurrence and richness of wildlife species represent a powerful tool to examine the current status of

finches), snakes, lizards, etc.

40 Tropical Forests - New Edition

2.3. Tropical coniferous forests

atricapillus, Garrulax palliatus, Napothera rufipectus, etc.).

3. Ecological importance of tropical forests

Currently, tropical forests are facing severe potential threats due to human interventions, such as extensive habitat loss and degradation, isolation, and fragmentation due to heavy exploitation and conversions into agricultural fields and residential areas [29–31], which create a complex spatial disturbance [32–34]. More than 50% of the tropical forest areas have been lost during the past two decades through extensive deforestation for timber, fuelwood, agricultural expansion, and human-induced fire [35–37].

It has been stated that habitat loss and fragmentation of tropical forest is a major threat for wildlife species composition, relative abundance, species richness, and density, that is, it increases higher predation risk, reduced food occurrence and diversity, and genetic variability of birds, mammals, amphibians, and reptiles [38–43]. This may alter habitat thus makes it less productive and attractive thus caused the shift of wildlife species into human-dominated landscape that might be unsuitable and less productive for them [44–48]. However, the consequence of habitat loss and degradation may vary from species to species depending upon the nature and extent of habitat alteration, availability of food resources, and the rate of predation and parasitism [49, 50].

In addition, climate change is an important factor, which has effects on wildlife species phenology, geographic distribution, physiology, vegetation composition, and food resources [51, 52]. Thus, it ultimately exerts negative effects on the population community parameters of the species, i.e., some becomes endangered, vulnerable, and threatened [53–55]. This might be that the climate change may cause the rising of temperature and declining of the precipitation, which make the tropical forest dry and highly susceptible to fire and prone them into shrub lands, grassland, and savannah. The alteration in microclimate may alter the vegetation species composition, richness, and diversity [56, 57].
