Implications of Anthropogenic Disturbances for Species Diversity, Recruitment and Carbon Density in the Mid-hills Forests of Nepal

doi:10.5814/j.issn.1674-764x.2021.01.001

Abstract

Abstract:

Almost three-fourths of forests are experiencing anthropogenic disturbances globally, and more than two-thirds of the forests in Nepal receive different types of disturbances. In community forests (CFs), local communities are dependent on the ecosystem services provided by the forests for various aspects of their livelihoods, which disturb the forests’ natural conditions and ecosystem functioning in a variety of ways. This study tested the major disturbance factors that had influential roles on plant species diversity, recruitment (seedlings and saplings), biomass, soil organic carbon (SOC) and total carbon density in two community-managed forests in the Mid-hills of Nepal. The stump number, cut-off seedlings and saplings, lopping, dropping, and grazing/trampling were used as measures of the major anthropogenic disturbances. The necessary data were collected from 89 randomly selected sample plots, each with an area of 250 m². The responses to anthropogenic disturbances were analyzed using Generalized Linear Models (GLM). The results showed that forest lopping was the most significant anthropogenic disturbance for biomass and total carbon density balance. A higher degree of lopping in the forests resulted in a lowering of the forests' carbon stock in the study area. SOC showed no significant response to any of the tested anthropogenic disturbances. Woody species richness and number of saplings increased with an increasing number of stumps, which signifies that intermediate disturbance was beneficial. However, a higher intensity of lopping reduced the sapling density. Grazing/trampling was the most significant disturbance for inhibiting seedling growth. Areas in the forests with a higher intensity of trampling showed lower numbers of seedlings and saplings. These results will be a guide for managing anthropogenic disturbances in multiple-use forests in Nepal, as well as those in similar socio-economic environments worldwide.

Key words: anthropogenic disturbance, biomass, carbon density, community-managed forest, seedlings and saplings, woody plants’ diversity

Hari Prasad PANDEY. Implications of Anthropogenic Disturbances for Species Diversity, Recruitment and Carbon Density in the Mid-hills Forests of Nepal[J]. Journal of Resources and Ecology, 2021, 12(1): 1-10.

Figures/Tables 6

References 37

[1]	Acharya K P, Dagi R B, Acharya M. 2011. Understanding forest degradation in Nepal. Unasylva, 62: 31-38.
[2]	Allnutt T F, Asner G P, Golden C D, et al. 2013. Mapping recent deforestation and forest disturbance in northeastern Madagascar. Tropical Conservation Science, 6(1):1-15. DOI URL
[3]	ANSAB. 2010. Forest carbon stock measurement: Guidelines for measuring carbon stocks in the community-managed forest. Asia Network for Sustainable Agriculture and Bio-resources (ANSAB), Federation of Community Forest Users, Nepal (FECOFUN), International Centre for Integrated Mountain Development (ICIMOD), Norwegian Agency for Development Cooperation (NORAD), 76. www.ansab.org.
[4]	ANSAB. 2011. Forest carbon stock in community forests in three watersheds (Ludikhola, Kayarkhola and Charnawati). Asia Network for Sustainable Agriculture and Bio-resources (ANSAB), Federation of Community Forest Users, Nepal (FECOFUN), International Centre for Integrated Mountain Development (ICIMOD).
[5]	Baral S K, Katzensteiner K. 2009. Diversity of vascular plant communities along a disturbance gradient in a central mid-hill community forest of Nepal. Banko Janakari, 19(1): 3-10.
[6]	Barlow J, Lennox G, Ferreira J, et al. 2016. Anthropogenic disturbance in tropical forests can double biodiversity loss from deforestation. Nature, 535: 144-147. DOI URL PMID
[7]	CFUG. 2008. Constitution and operational plan of community forest user groups. Gorkha: Community Forest User Groups (Ghaledanda Ranakhola CFUG and Ludi Damgade CFUG).
[8]	Chave J, Andalo C, Brown S. 2005. Tree allometry and estimation of carbon stocks. Oecologia, 145(1): 87-99. DOI URL
[9]	Chhettri N, Sharma E, Deb D C. 2002. Impact of firewood extraction on tree structure, regeneration and woody biomass productivity in a trekking corridor of the Sikkim Himalaya. Mountain Research and Development, 22(2): 150-158. DOI URL
[10]	DDC. 2011. District profile of Gorkha. Gorkha: District Development Committee.
[11]	DFRS. 2015a. State of Nepal’s forests. Forest Resource Assessment (FRA) Nepal, Department of Forest Research and Survey (DFRS). Kathmandu, Nepal.
[12]	DFRS. 2015b. Middle mountains forests of Nepal. Forest Resource Assessment (FRA) Nepal, Department of Forest Research and Survey (DFRS). Kathmandu, Nepal.
[13]	FAO. 2020. Global forest resources assessment 2020—Key Findings. Rome.
[14]	Gautam T P, Mandal T N. 2016. Effect of disturbance on biomass, production and carbon dynamics in the moist tropical forest of eastern Nepal. Forest Ecosystems, 3:11. DOI: 10.1186/s40663-016-0070-y. DOI URL
[15]	Geider R J, Delucia E H, Falkowski P G. 2001. Primary productivity of planet earth: Biological determinants and physical constraints in terrestrial and aquatic habitats. Global Change Biology, 7: 849-882. DOI URL
[16]	IPCC. 2006. IPCC guidelines for national greenhouse gas inventories: Intergovernmental panel on climate change, national greenhouse inventory program. United Nations Environment Program (UNEP).
[17]	IPCC. 2007. Climate change: Impacts, adaptation and vulnerability. Contribution of Working Group II to the fourth assessment report of the Intergovernmental Panel on Climate Change. Cambridge, UK: Cambridge University Press.
[18]	Marion-Kissling K, Hegetschweiler T, Rusterholz H P. 2009. Short-term and long-term effects of human trampling on above-ground vegetation, soil density, soil organic matter and soil microbial processes in suburban beech forests. Applied Soil Ecology, 42(3): 303-314. DOI URL
[19]	MacDicken K. 1997. A guide to monitoring carbon storage in forestry and agroforestry projects arlington (VA). Forest Carbon Monitoring Programme, Winrock International Institute for Agriculture Development.
[20]	Moreno-Mateos D, Barbier E, Jones P, et al. 2017. Anthropogenic ecosystem disturbance and the recovery debt. Nature Communications, 8:14163. DOI: 10.1038/ncomms14163. DOI URL PMID
[21]	Pandey H, Pandey P, Pokhrel S, et al. 2019. Relationship between soil properties and forests carbon: Case of three community forests from Far Western Nepal. Banko Janakari, 29(1): 43-52. DOI URL
[22]	Paudyal K, Baral H, Burkhard B. 2015. Participatory assessment and mapping of ecosystem services in a data-poor region: A case study of community-managed forests in central Nepal. Ecosystem Services, 13: 81-92. DOI URL
[23]	Poudyal B H, Maraseni T, Cockfield G. 2019. Impacts of forest management on tree species richness and composition: Assessment of forest management regimes in Tarai landscape Nepal. Applied Geography, 111: 1-11.
[24]	Pawar G V, Singh L, Jhariya M K, et al. 2014. Effect of anthropogenic disturbances on biomass and carbon storage potential of a dry tropical forest in India. Journal of Applied and Natural Science, 6(2): 383-392. DOI URL
[25]	Pearson T R, Brown S L, Birdsey R A. 2007. Measurement guidelines for the sequestration of forest carbon. Northern Research Station, Department of Agriculture, USA.
[26]	Rana E, Thwaites R, Luck G. 2017. Trade-offs and synergies between carbons, forest diversity and forest products in Nepal community forests. Environmental Conservation, 44(1): 5-13. DOI URL
[27]	R Core Team. 2018. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria.
[28]	Sahu P K, Sagar R, Singh J S. 2008. Tropical forest structure and diversity in relation to altitude and disturbance in a Biosphere Reserve in central India. Applied Vegetation Science, 11(4): 461-470. DOI URL
[29]	Sapkota I P, Tigabu M, Odén P C. 2009. Spatial distribution, advanced regeneration and stand structure of Nepalese Sal(Shorea robusta) forest subject to disturbances of different intensities. Forest Ecology and Management, 257(9): 1966-1975. DOI URL
[30]	Sapkota I P, Tigabu M, Odén P C. 2010. Changes in tree species diversity and dominance across a disturbance gradient in Nepalese Sal (Shorea robusta Gaertn.) forests. Journal of Forest Research, 21: 25-32.
[31]	Sharma E, Chhettri N. 2005. ICIMOD’s transboundary biodiversity management initiative in the Hindu Kush-Himalayas. Mountain Research and Development, 25(3): 278-281. DOI URL
[32]	Shrestha K B, Maren I E, Arneberg E, et al. 2013. Effect of anthropogenic disturbance on plant species diversity in oak forests in Nepal, Central Himalaya. International Journal of Biodiversity Science, Ecosystem Services & Management, 9: 21-29.
[33]	Sodhi S, Lee T M, Koh L P, et al. 2009. A meta-analysis of the impact of anthropogenic forest disturbance on southeast Asia’s biotas. Biotropica, 41(1): 103-109. DOI URL
[34]	Soni A, Decesari S, Shridhar V, et al. 2019. Investigation of potential source regions of atmospheric Black Carbon in the data deficit region of the Western Himalayas and its foothills. Atmospheric Pollution Research, 10(6): 1832-1842. DOI URL
[35]	Tamrakar P R. 2000. Biomass and volume tables with species. Description for Community Forest Management, Ministry of Forest and Soil Conservation, Nepal.
[36]	Thapa S, Chapman D S. 2010. Impacts of resource extraction on forest structure and diversity in Bardia National Park, Nepal. Forest Ecology and Management, 259(3): 641-649. DOI URL
[37]	Walkley A, Black I A. 1934. An examination of the method for determining soil organic matter, and a proposed modification of the chromic acid titration method. Soil Science, 37(1): 29-38. DOI URL

S.N.	Variables	Unit	Quantity	Remarks
1	Species richness	number of species	26.00	Woody habit only
2	Tree density	number ha^-1	1468.80
3	Sapling density	number ha^-1	2695.80	Recruitments or regeneration
4	Seedling density	number ha^-1	32522.00	Recruitments or regeneration
5	Biomass density	t ha^-1	151.15
6	SOC density	t ha^-1	46.76
7	Total carbon density	t ha^-1	117.80

S.N.	Variables	Unit	Quantity	Remarks
1	Species richness	number of species	26.00	Woody habit only
2	Tree density	number ha^-1	1468.80
3	Sapling density	number ha^-1	2695.80	Recruitments or regeneration
4	Seedling density	number ha^-1	32522.00	Recruitments or regeneration
5	Biomass density	t ha^-1	151.15
6	SOC density	t ha^-1	46.76
7	Total carbon density	t ha^-1	117.80

Attributes	Disturbances	DF	Deviance	Resid. DF	Resid. Deviance	F-value	P-value	Sig.
Species richness	Number of stumps	1	5.796	87	83.82	6.5418	0.0125	Yes
	Degree of lopping	3	0.408	84	83.41	0.1537	0.9270	No
	Degree of cutting	3	4.774	81	78.64	1.7964	0.1549	No
	Dropping count	1	0.219	80	78.42	0.2471	0.6205	No
	Degree of trampling	3	5.944	77	72.48	2.2365	0.0907	No
Number of saplings	Number of stumps	1	148.035	87	1554.60	8.7686	0.0041	Yes
	Degree of lopping	3	168.849	84	1385.70	3.3338	0.0237	Yes
	Degree of cutting	3	11.427	81	1374.30	0.2256	0.8783	No
	Dropping count	1	31.542	80	1342.80	1.8687	0.1756	No
	Degree of trampling	3	64.271	77	1278.50	1.2690	0.2901	No
Number of seedlings	Number of stumps	1	2.348	87	345.69	0.6518	0.4220	No
	Degree of lopping	3	3.197	84	342.49	0.2959	0.8283	No
	Degree of cutting	3	15.074	81	327.42	1.3950	0.2507	No
	Dropping count	1	2.807	80	324.61	0.7792	0.3801	No
	Degree of trampling	3	42.268	77	282.34	3.9116	0.0118	Yes
SOC density	Number of stumps	1	0.576	87	267.18	0.1863	0.6672	No
	Degree of lopping	3	19.920	84	247.26	2.1470	0.1011	No
	Degree of cutting	3	4.196	81	243.07	0.4523	0.7164	No
	Dropping count	1	1.272	80	241.80	0.4111	0.5233	No
	Degree of trampling	3	9.642	77	232.15	1.0392	0.3801	No
Total biomass density	Number of stumps	1	0.240	87	9885.60	0.0022	0.9624	No
	Degree of lopping	3	1048.380	84	8837.20	3.1911	0.0282	Yes
	Degree of cutting	3	380.290	81	8456.90	1.1575	0.3315	No
	Dropping count	1	57.820	80	8399.10	0.5280	0.4697	No
	Degree of trampling	3	488.810	77	7910.30	1.4879	0.2245	No
Total carbon density	Number of stumps	1	0.050	87	2843.70	0.0014	0.9699	No
	Degree of lopping	3	367.040	84	2476.70	3.7827	0.0138	Yes
	Degree of cutting	3	85.480	81	2391.20	0.8810	0.4548	No
	Dropping count	1	21.050	80	2370.20	0.6508	0.4223	No
	Degree of trampling	3	132.510	77	2237.60	1.3657	0.2596	No

Attributes	Disturbances	DF	Deviance	Resid. DF	Resid. Deviance	F-value	P-value	Sig.
Species richness	Number of stumps	1	5.796	87	83.82	6.5418	0.0125	Yes
	Degree of lopping	3	0.408	84	83.41	0.1537	0.9270	No
	Degree of cutting	3	4.774	81	78.64	1.7964	0.1549	No
	Dropping count	1	0.219	80	78.42	0.2471	0.6205	No
	Degree of trampling	3	5.944	77	72.48	2.2365	0.0907	No
Number of saplings	Number of stumps	1	148.035	87	1554.60	8.7686	0.0041	Yes
	Degree of lopping	3	168.849	84	1385.70	3.3338	0.0237	Yes
	Degree of cutting	3	11.427	81	1374.30	0.2256	0.8783	No
	Dropping count	1	31.542	80	1342.80	1.8687	0.1756	No
	Degree of trampling	3	64.271	77	1278.50	1.2690	0.2901	No
Number of seedlings	Number of stumps	1	2.348	87	345.69	0.6518	0.4220	No
	Degree of lopping	3	3.197	84	342.49	0.2959	0.8283	No
	Degree of cutting	3	15.074	81	327.42	1.3950	0.2507	No
	Dropping count	1	2.807	80	324.61	0.7792	0.3801	No
	Degree of trampling	3	42.268	77	282.34	3.9116	0.0118	Yes
SOC density	Number of stumps	1	0.576	87	267.18	0.1863	0.6672	No
	Degree of lopping	3	19.920	84	247.26	2.1470	0.1011	No
	Degree of cutting	3	4.196	81	243.07	0.4523	0.7164	No
	Dropping count	1	1.272	80	241.80	0.4111	0.5233	No
	Degree of trampling	3	9.642	77	232.15	1.0392	0.3801	No
Total biomass density	Number of stumps	1	0.240	87	9885.60	0.0022	0.9624	No
	Degree of lopping	3	1048.380	84	8837.20	3.1911	0.0282	Yes
	Degree of cutting	3	380.290	81	8456.90	1.1575	0.3315	No
	Dropping count	1	57.820	80	8399.10	0.5280	0.4697	No
	Degree of trampling	3	488.810	77	7910.30	1.4879	0.2245	No
Total carbon density	Number of stumps	1	0.050	87	2843.70	0.0014	0.9699	No
	Degree of lopping	3	367.040	84	2476.70	3.7827	0.0138	Yes
	Degree of cutting	3	85.480	81	2391.20	0.8810	0.4548	No
	Dropping count	1	21.050	80	2370.20	0.6508	0.4223	No
	Degree of trampling	3	132.510	77	2237.60	1.3657	0.2596	No