Citation: Janice Liang, Travis Reynolds, Alemayehu Wassie, Cathy Collins, Atalel Wubalem. Effects of exotic Eucalyptus spp. plantations on soil properties in and around sacred natural sites in the northern Ethiopian Highlands[J]. AIMS Agriculture and Food, 2016, 1(2): 175-193. doi: 10.3934/agrfood.2016.2.175
[1] | Hans-Georg Schwarz-v. Raumer, Elisabeth Angenendt, Norbert Billen, Rüdiger Jooß . Economic and ecological impacts of bioenergy crop production—a modeling approach applied in Southwestern Germany. AIMS Agriculture and Food, 2017, 2(1): 75-100. doi: 10.3934/agrfood.2017.1.75 |
[2] | Francisco L. Pérez . Viticultural practices in Jumilla (Murcia, Spain): a case study of agriculture and adaptation to natural landscape processes in a variable and changing climate. AIMS Agriculture and Food, 2016, 1(3): 265-293. doi: 10.3934/agrfood.2016.3.265 |
[3] | W. Mupangwa, I. Nyagumbo, E. Mutsamba . Effect of different mulching materials on maize growth and yield in conservation agriculture systems of sub-humid Zimbabwe. AIMS Agriculture and Food, 2016, 1(2): 239-253. doi: 10.3934/agrfood.2016.2.239 |
[4] | Helmi Helmi, Hairul Basri, Sufardi, Helmi Helmi . Analysis of soil water balance and availability on several land use types for hydrological disaster mitigation in Krueng Jreu Sub-watershed. AIMS Agriculture and Food, 2020, 5(4): 950-963. doi: 10.3934/agrfood.2020.4.950 |
[5] | Boris Boincean, Amir Kassam, Gottlieb Basch, Don Reicosky, Emilio Gonzalez, Tony Reynolds, Marina Ilusca, Marin Cebotari, Grigore Rusnac, Vadim Cuzeac, Lidia Bulat, Dorian Pasat, Stanislav Stadnic, Sergiu Gavrilas, Ion Boaghii . Towards Conservation Agriculture systems in Moldova. AIMS Agriculture and Food, 2016, 1(4): 369-386. doi: 10.3934/agrfood.2016.4.369 |
[6] | Widowati, Sutoyo, Hidayati Karamina, Wahyu Fikrinda . Soil amendment impact to soil organic matter and physical properties on the three soil types after second corn cultivation. AIMS Agriculture and Food, 2020, 5(1): 150-168. doi: 10.3934/agrfood.2020.1.150 |
[7] | Jan Willem Erisman, Nick van Eekeren, Jan de Wit, Chris Koopmans, Willemijn Cuijpers, Natasja Oerlemans, Ben J. Koks . Agriculture and biodiversity: a better balance benefits both. AIMS Agriculture and Food, 2016, 1(2): 157-174. doi: 10.3934/agrfood.2016.2.157 |
[8] | I. Bashour, A. AL-Ouda, A. Kassam, R. Bachour, K. Jouni, B. Hansmann, C. Estephan . An overview of Conservation Agriculture in the dry Mediterranean environments with a special focus on Syria and Lebanon. AIMS Agriculture and Food, 2016, 1(1): 67-84. doi: 10.3934/agrfood.2016.1.67 |
[9] | A. Nurbekov, A. Akramkhanov, A. Kassam, D. Sydyk, Z. Ziyadaullaev, J.P.A. Lamers . Conservation Agriculture for combating land degradation in Central Asia: a synthesis. AIMS Agriculture and Food, 2016, 1(2): 144-156. doi: 10.3934/agrfood.2016.2.144 |
[10] | Maurizio Quartieri, Elena Baldi, Giovambattista Sorrenti, Graziella Marcolini, Moreno Toselli . Effect of agro-industry by-product on soil fertility, tree performances and fruit quality in pear (Pyrus communis L.). AIMS Agriculture and Food, 2016, 1(1): 20-32. doi: 10.3934/agrfood.2016.1.20 |
The Smart Grid is an attempt at modernizing the current existing electric grid by incorporating modern technologies such as two way digital communications and other methodologies widely adopted by the modern day Internet. It interconnects various operational components such as bulk generation,transmission,and distribution across multiple parties including service provider,end users,and markets. It aims to increase reliability,efficiency and security of the grid [1, 2, 3].
The Smart Grid uses concepts such as Time of Use (TOU) pricing techniques to address the issue of running peak power plants by reducing the frequency and lengths of the peak demand periods thus decreasing the need of these peak plants. TOU pricing is simply defined as different prices for different periods of the day and would incentivize users shift their device usage periods to off peak hours [4]. Such techniques have shown to reduce peak power consumptions in residential household markets by approximately and as statistics show from Connecticut light and Power and Pacific Gas and Electric respectively [5].
Distributed Generation (aka on-site power generation or Dispersed Generation) is also viewed as a solution to the utility company issues with peak demand periods in the Smart Grid. This refers to decentralized in house generation of power by the use of windmills or solar panels to take advantage of renewable energy sources to generate energy and sell back to the grid. Incentives are provided to consumers willing to install the needed equipment and to sell energy back to the grid [6, 7]. The size of an incentive would not only be determined by the amount of energy sold back but also by the precise instant of transactions in a TOU pricing based market [8, 9].
The complexity of decision making of when to sell back energy by the user would increase with the dynamics of changing prices in a TOU market. In typical distributed generation environments,producers would try to maximize rewards by storing generated energy through storage devices and sell them when the incentive rate is high. Actions such as when and how much energy to sell could be determined by observing the trend of the varying prices. The producer invariably prefers selling off energy during peak price periods before the price drops. She needs to decide how much to sell based on predictions of future price variation and the capacity of the storage device. In cases where the storage device becomes full,she has to sell energy irrespective of the price given during that period. The other factors that influence the decision making are the cost of storing energy and the efficiency of the device at storing energy in terms of minimizing inherent energy losses over time. This decision making process to determine when and how much energy to sell back could be time consuming if the computation was to be done manually. Thus exploring algorithms that would compute the optimal policy is necessary.
In this paper,we report an empirical analysis of applying reinforcement learning (RL) to the problem of maximizing the reward of selling back energy. We first identify a set of variables that can effectively represent current state of the market as well as the storage characteristics of the power generation unit. Then we apply Q-learning to adaptively estimate the best decision. To demonstrate the effectiveness of the RL approach,we compare its performance to a naive greedy approach.
The remainder of the paper is organized as follows. In the next section,we will review related work and point out our main contribution. The tariff market model introduced in [10] will be briefly reviewed in Section 3. The proposed producer strategy optimization algorithm based on Q-learning will be introduced in Section 4. For completeness,a brief review of Q-learning will be given. Results analysis are provided in Section 5 followed by a succinct conclusion.
Reinforcement Learning (RL) has been widely used in the area of power markets particularly on the wholesale markets side aiding in the auction based pricing mechanism used for the bidding of electricity. In [11],the market power of the participating parties in Day Ahead markets were studied modeling such markets as competitive Markov decision processes and using RL based approaches a a tool to solve such games. In [12],a comparison of a game theoretical Nash Equilibrium based approach and RL based behavior using the Q-learning algorithm is used to study the interactions between the various bulk generators. A model to study the tacit collusive behavior of the wholesale market participants was proposed in [13] where the power market scenario was modeled as a repeated interaction game with imperfect information. In [14] the multi bulk generators in the auction market are modeled as multiple agents with the objective of profit and utilization rate maximization and the interaction is studied in a market scenario with network constraints using a Q Learning based RL approach. [15] looks at a multi agent RL approach taking into account congestion management in the network simulated by capacity constraints on the transmission lines.
There has also been some recent work on the retail side of the electricity market. The interaction between the energy retailers and the consumers strategies were studied in [16]. The system was modeled as a multi agent RL scenario using Q-learning and game theory equilibrium concepts was used to analyze the results. The management of storage devices in homes was studied using agent based modeling techniques and game theory in [17]. The prediction of the user comfort level with different patterns of device usage was studied using supervised machine learning algorithms namely Support Vector Machines,Multilayer Perceptron and Naive Bayes in [18]. In [10],the concept of a tariff market had been introduced for the Smart Grid. The tariff market would consist several “self interested” broker agents to represent energy retailers with a unique portfolio of customers. The customer population would include the producers and consumers of electricity. Broker Agent strategy for profit maximization was studied using Q-learning in [19]. The learning strategy was shown to be much superior to other non learning strategies such as a Random strategy,a Balanced strategy and a Greedy Strategy. The work was extended in [20] to include multiple autonomous agents for the various brokers deriving their respective optimal policies independently.
Much of the literature on the retailer side of the electricity market have either talked about the interaction between the consumer and the retailer or the action of the broker using learning strategies. While they do address the action of the utility company,to the best of our knowledge,no prior work have taken into account the complex decision making process of the distributed producers in a RTP based pricing environment. The main contribution of this work is that we fill this gap by providing an empirical analysis of applying RL to the problem of maximizing user discounted total rewards of selling back energy for a RTP based pricing environment.
We utilize the tariff market introduced in [10] as the basic environment for our model. The tariff market concerns the retail side of the electricity market and consists of 3 different entities namely the broker agents,producers and consumers. The broker agents are in reality commercial utilities or cooperatives trying to broker deals with the customer population. The customer population is made up of consumers and producers of electricity. Consumers make up the demand side of the market and include homes,small businesses,and commercial enterprises. The producers,on the other hand,make up the supply part of the tariff market.
Producers include nano grids,micro grids and homes generating power locally using windmill. The producer invariably makes use of a storage device in order to save the generated electricity and sell at a later period when the price of electricity is high. The amount of energy that a producer can store is subject to its maximum storage which in turn is determined by the storage cost. Typically,producer would like to sell energy and earn capital early as the capital can be used elsewhere. This can be modeled with a discount factor which widely used in finance and was first introduced by Paul Samuelson in 1938 [21]. Alternative,a producer may also like to reserve some energy for industrial use that may lead to a positive cash flow. In this paper,we will model it as an inelastic load with small perturbation. Moreover,energy stored in the storage is subject to energy loss. Since the voltage of battery is relatively stable,it is reasonable to assume that the energy loss,which is a function of voltage alone,is constant. The reward of the producer can be modeled as the adjusted monetary gain of selling energy after taking discount factor into account.
The consumer population of the tariff market include households,small enterprises and large industries. They make up the demand profile for the tariff market. The consumers have the freedom to switch to any broker according to their preferences. To illustrate the switching behavior of the consumer,we follow the action model enforced by [19]. The consumers rank the various brokers at every time slot. However,a consumer may not always make contract with the broker agent of the lowest offered tariff price as factors such as green energy and tariff contract clauses should be taken into consideration for decision making. As in [19],we model this by ranking the broker agents with price and then consumer will select a broker with a probability based on its price ranking.
The broker agent tries to balance supply and demand between its customer portfolio of consumers and producers. This is achieved by adjusting the producer and consumer tariffs. We assume the broker agent to adopt a balanced strategy for the price variation. When there is a shortage of supply,the broker would increase both the consumer and producer prices and if there is an abundance of supply,the broker agent would then reduce both prices. Although this is an adaptive strategy,it does not learn from the past.
There is a constant interaction that takes place between the broker agents,consumers and producers. The producers publishes consumer and producer prices for the given time slot. According to the consumer prices,the consumers would choose a particular broker thus contributing to the demand portfolio of the chosen broker. According to the producer tariffs published,the producers would choose when,how much and which broker to sell energy. This would sum up the supply portfolio for the broker. The broker would then decide how to vary his prices for the next time slot according to the balanced strategy. Thus there is repeated interaction and a dynamic portfolio construction for every time slot.
We make a few assumptions for our model. Time is discretized into multiple fixed length time slots. The energy unit traded among the players and broker prices are also discretized. The transaction of selling or buying energy is also assumed to last no more than one time slot. The producer and consumer tariffs are assumed to be constant for any given time slot.
In this section we describe the proposed solution for determining optimal selling strategy for maximizing rewards for the producer using Q-learning [22, 23]. Being a type of RL,Q-learning can be best described using the Markov decision process (MDP) [24]. Q-learning computes the optimal policy by learning an action-value function that gives the expected payoff for taking an action in a given state and following a fixed policy thereafter. One strength of Q-learning is that it is a model-free method,meaning it does not require a model of the environment such as the transition probabilities from one state to another state given a particular action is taken. For the ease of exposition,we really briefly review Q-learning before describing how it is used for strategy optimization.
The key of Q-learning is to estimate the reward function Q(s, a) for taking an action a' when the current state of the system is s'. If we assume that Q(s, a) is known,apparently the appropriate action at state s' is simply
![]() |
(1) |
However,since Q(s, a) is not known initially,(1) generally will not result in an optimal action. Instead,a “Q-learner” sometimes simply selects an action randomly. The literatures typically the former choice (using (1)) as exploitation and the latter (with randomly selected action) as exploration. As the learned Q(s, a) becomes more accurate as iterations go,the frequency of using exploitation to exploration increases.
Regardless of whether exploitation or exploration is used,the estimated reward function can be refined by
![]() |
(2) |
where s' is the observed next state after action a
(2) can be interpreted rather intuitively. When the learning rate α=1
The general update rule in (2) for α<1
To utilize Q-learning,we need to determine the available actions and states of the producer. We assume that there are Nbroker
As for the state of the MDP,the producer only uses the current price of each broker and the amount of energy stored to determine his current state. Therefore,the state variable s
The simulation model described in Section 3 is configured as follows. The environment is initialized with 250 consumers,3 brokers and 30 producers. The per consumer load per time slot (hour) is configured to 1 kWh. A fixed uniform distribution is used to model customer preferences for choosing brokers with the least expensive broker getting 50% of the customers and the other two getting 30% and 20%,respectively. The initial prices of the three brokers are $
At the beginning,we assume all producers sell energy based on the similar rule of thumb as the consumers. Namely,they will sell energy to the broker offered highest price with 50% chance,and the second highest price with 30% chance,and lowest price with 20% chance. Moreover,they will sell all of their energy in each time slot (hour) and storing no energy. Then,we assume that one of the producers change his strategy with the proposed Q-learning method. We then investigate the effectiveness of our approach by comparing it to the greedy strategy [19]. That is,selling all energy in each time slot (hour) to the broker with the highest offering price. The greedy strategy is adaptive since it reacts the current condition of the market but does not learn from the past experience.
In each simulation,we fix the number of episodes[1] to 2000 and time slots (hours) per episode to 5000. Figure 2 shows the increase in the total discounted reward comparing to the greedy agents. The result clearly shows proposed RL approach learns from the past experience and improves over time. At the initial learning stage,the learning agent explores the environment to gain experience thus it performs worse than greedy agents but over time the learning agent learns a better strategy and outperforms the greedy agent.
The intermittency of energy generation through windmills is a key concern for the smart-grid integration of distributed generators. Here we consider how the learned strategy performs when compared with the adaptive greedy approach. For this evaluation,we apply Poisson noise to the energy generation rate and vary the variance λ
Figure 3 shows the increase in per-episode discounted total reward comparing to the greedy approach. With λ=1
The storage device allows the energy generated to be stored for future selling when the price is high. The energy storage gives producers more flexibility. To study the factor the storage size plays in maximizing total reward,in this experiment we consider how the learning agent performs given different storage sizes.
The result in Figure 4 shows that with a small storage size of 25,the learning is less effective comparing to that in the rest cases. After 2000 episodes of learning,the learning agent still perform inferior to the greedy agent. Though the performance increases steadily,the progress is low and the training takes a measurable longer time. On the other hand,with a larger storage size,the learning agent reaches comparable level of performance in 600 episodes and finally develops a learned policy that outperforms the greedy policy by 2%. This experiment shows that the storage size has a remarkable impact on both effectiveness of training and the performance of the learned strategies.
In this paper,we propose to use Q-learning to optimize the timing and the quantity of energy a distributed producer should sell to a broker. We compare our result with greedy approach under a realistic tarrif market model introduced in [19]. Our simulation results show a notable gain over the greedy approach. Moreover,we study the effects of increase variation of energy generation rate and change of storage to the proposed algorithm.
The authors would like to thank Professor Amy McGovern for sharing her experience of machine learning.
All authors declare no conflicts of interest in this paper.
[1] | Stanturf JA, Vance ED, Fox TR, et al. (2013) Eucalyptus beyond Its Native Range: Environmental Issues in Exotic Bioenergy Plantations. Int J For Res 2013:463030. |
[2] | Zegeye H (2010) Environmental and Socio-economic Implications of Eucalyptus in Ethiopia. Ethiop Inst Agric Res2010: 184-205. |
[3] | Pohjonen V (1989) Establishment of fuelwood plantations in Ethiopia. Silva Cerelica 14: 1-388. |
[4] | Leicach SR, Grass MAY, Chludil HD, et al. (2012) Chemical Defenses in Eucalyptus Species: A Sustainable Strategy Based on Antique Knowledge to Diminish Agrochemical Dependency. New Advances and Contributions to Forestry Research. INTECH Open Access Publisher. |
[5] |
Zhang C, Fu S (2009) Allelopathic effects of eucalyptus and the establishment of mixed stands of eucalyptus and native species. For Ecol Manag 258: 1391-1396. doi: 10.1016/j.foreco.2009.06.045
![]() |
[6] | Yitaferu B, Abewa A, Amare T (2013) Expansion of Eucalyptus Woodlots in the Fertile Soils of the Highlands of Ethiopia: Could It Be a Treat on Future Cropland Use?. J Agric Sci 5: 97-107. |
[7] | Bean C, Russo MJ. Element Stewardship Abstract for Eucalyptus globlus. The Nature Conservancy, 1989. Available from: http://www.invasive.org/gist/esadocs/documnts/eucaglo.pdf |
[8] | Davidson J (1989) The Eucalyptus Dilemma: Arguments For and Against Eucalypt Planting in Ethiopia. Eur Econ Rev 50: 1245-1277. |
[9] | Dessie G, Erkossa T (2011) Eucalyptus in East Africa. FAO. |
[10] | Palmberg C (2002) Annotated Bibliography on Environmental, Social and Economic Impacts of Eucalypts. FAO. |
[11] |
Jagger P, Pender J (2003) The role of trees for sustainable management of less-favored lands: the case of eucalyptus in Ehtiopia. For Policy Econ 5: 83-95. doi: 10.1016/S1389-9341(01)00078-8
![]() |
[12] |
Kidanu S, Mamo T, Stroosnijder L (2005) Biomass production of Eucalyptus boundary plantations and their effect on crop productivity on Ethiopian highland Vertisols. Agroforestry Forum 63: 281-290. doi: 10.1007/s10457-005-5169-z
![]() |
[13] |
Harrington RA, Ewel JJ (1997) Invasibility of tree plantations by native and non-native plant species in Hawaii. For Ecol Manag 99: 153-162. doi: 10.1016/S0378-1127(97)00201-6
![]() |
[14] | Lemenih M, Kassa H (2014) Re-Greening Ethiopia: History, Challenges and Lessons. Forests 4: 1896-1909. |
[15] | Chanie T, Collick AS, Adgo E, et al. (2013) Eco-hydrological impacts of Eucalyptus in the semi humid Ethiopian Highlands: the Lake Tana Plain. J Hydrol Hydromech 61: 21-29. |
[16] |
Yirdaw E (2001) Diversity of naturally-regenerated native woody species in forest plantations in the Ethiopian highlands. New For 22: 159-177. doi: 10.1023/A:1015629327039
![]() |
[17] | Heilman P, Norby RJ (1997) Nutrient cycling and fertility management in temperate short rotation forest systems. Biomass Bioenerg 14: 361-371. |
[18] | Zewdie M (2008) Temporal changes of biomass production, soil properties, and ground flora in Eucalyptus globulus plantations in the central highlands of Ethiopia. [PhD]. Uppsala: Swedish University of Agricultural Sciences. |
[19] | Sunder SS (1993) The Ecological, Economic and Social Effects of Eucalyptus. FAO Corporate Document Repository1. |
[20] | Poore MED, Fries C (1985) The ecological effects of eucalyptus. FAO For Paper 59. |
[21] |
Nyssen J, Poesen J, Moeyersons J, et al. (2004) Human impact on the environment in the Ethiopian and Eritrean highlands -- a state of the art. Earth-Sci Rev 64: 273-320. doi: 10.1016/S0012-8252(03)00078-3
![]() |
[22] |
Pohjonen V, Pukkala T (1990) Eucalyptus globulus in Ethiopian Forestry. For Ecol Manag 36: 19-31. doi: 10.1016/0378-1127(90)90061-F
![]() |
[23] | Teshome T (2009) Is Eucalyptus Ecologically Hazardous Tree Species? Ethiop e-J Res Innov Foresight 1: 128-134. |
[24] |
Teketay D (1992) Human impact on a natural montane forest in south eastern Ethiopia. Ethiop e-J ResInnov Foresight 1: 128-134. |
[25] | Aerts R, Overtveld KV, November E, et al. (2016) Conservation of the Ethiopian church forests: Threats, opportunities, and implications for their management. Sci Total Environ551: 404-414. |
[26] | Reynolds T, Sisay TS, Wassie A, et al. (2015) Sacred natural sites provide ecological libraries for landscape restoration and institutional models for biodiversity conservation. GSDR Brief. |
[27] | Bongers F, Wassie A, Sterck FJ, et al. (2006) Ecological restoration and church forests in northern Ethiopia. J Drylands 1: 35-44. |
[28] |
Wassie A, Sterck FJ, Bongers F (2010) Species and structural diversity of church forests in a fragmented Ethiopian Highland landscape. J Veg Sci 21: 938-948. doi: 10.1111/j.1654-1103.2010.01202.x
![]() |
[29] | Wassie A (2007) Ethiopian church forests: opportunities and challenges for restoration. The Netherlands: Wageningen University. |
[30] | Mengist M (2011) Eucalyptus plantations in the highlands of Ethiopia revisited: A comparison of soil nutrient status after the first coppicing. Mountain Forestry Master Programme. |
[31] | Schulte EE, Hopkins BG (1996) Estimation of soil organic matter by weight loss on ignition. Soil organic matter: Analysis and interpretation. Madison, WI: Soil Science Society of America. 21-32. |
[32] | Mclean EO (1982) Soil pH and lime requirement. Methods of soil analysis. Madison, WI: ASA and SSSA. 199-223 |
[33] | Dahnke WC (1990) Testing soils for available nitrogen. Soil testing and plant analysis. Madison, WI: Soil Science Society of America. 120-140. |
[34] | Schlede H (1989) Distribution of acid soils and liming materials in Ethiopia. Ethiopian Institute of Geological Surveys. |
[35] | Olsen SR, Sommers LE (1982) Phosphorus. Methods of soil analysis. Madison, WI: ASA and SSSA. 403-430. |
[36] | Brady NC (1990) The Nature and Properties of Soils. New York, New York: Macmillan Publishing Company. |
[37] | Mekonnen K, Glatzel G, Sieghardt M, et al. (2009) Soil Properties under Selected Homestead Grown Indigenous Tree and Shrub Species in the Highland Areas of Central Ethiopia. East Afr J Sci 3: 9-17. |
[38] | Singwane SS, Malinga P (2012) Impacts of pine and eucalyptus forest plantations on soil organic matter content in Swaziland - Case of Shiselweni Forests. J Sustain Dev Afr 14: 137-151. |
[39] | Bot A, Benites J (2005) The importance of soil organic matter: Key to drough-resistant soil and sustained food and production. FAO. |
[40] |
Griffiths R, Madritch M, Swanson A (2009) The effects of topography on forest soil characteristics in the Oregon Cascade Mountains (USA): Implications for the effects of climate change on soil properties. For Ecol Manag 257: 1-7. doi: 10.1016/j.foreco.2008.08.010
![]() |
[41] | Garten C, Post W, Hanson P, et al. (1999) Forest carbon inventories and dynamics along a elevation gradient in the southern Appalachian Mountains. Biogeochemistry 45: 115-145. |
[42] | Sims Z, Nielsen G (1986) Organic carbon in Montana soils related to clay content and climate. Soil Sci Soc Am J 50: 1261-1271. |
[43] |
Ruiz-Sinoga JD, Romero-Diaz A (2010) Soil degradation factors along a Mediterranean physiometric gradient in Southern Spain. Geomorphology 118: 359-368. doi: 10.1016/j.geomorph.2010.02.003
![]() |
[44] | Raison R, Khanna P, Crane W (1982) Effects of intensified harvesting on rates of nitrogen and phosphorus removal from Pinus radiata and Eucalyptus forests in Australia and New Zealand. N Z J For Sci 12: 394-403. |
[45] |
Reganold J, Elliott L, Unger Y (1987) Long-term effects of organic and conventional farming on soil erosion. Nature 330: 370-372. doi: 10.1038/330370a0
![]() |
[46] | Ravina da Silva M (2012) Impact of Eucalyptus plantations on pasture land on soil properties and carbon sequestration in Brazil. Uppsala: Swedish University of Agricultural Sciences. |
[47] | Berthrong T, Jobbagy G, Jackson B (2009) A global meta-analysis of soil exchangeable cations, pH, carbon, and nitrogen with afforestation. Ecol Soc Am 19: 2228-2241. |
[48] |
Faria G, Barros NFd, Ferreira R (2009) Soil fertility, organic carbon and fractions of the organic matter at different distances from Eucalyptus stumps. Revista Brasileria de Cencia dosolo 33: 571-579. doi: 10.1590/S0100-06832009000300010
![]() |
[49] |
Lemenih M, Gidyelew T, Teketay D (2004) Effect of canopy cover and understory environment of tree plantations on richness, density and size of colonizing woody species in southern Ethiopia. For Ecol Manag 194: 1-10. doi: 10.1016/j.foreco.2004.01.050
![]() |
[50] | Turner J, Lambert M (2000) Changing in organic carbon in forest plantations soils in eastern Australia. For EcolManag 133:231-247. |
[51] |
Mensah AK (2015) Role of revegetation in restoring fertility of degraded mined soils in Ghana: A review. Int J Biodivers Convers 7: 57-80. doi: 10.5897/IJBC2014.0775
![]() |
[52] |
Michelsen A, Lisanework N, Friis I (1993) Impacts of tree plantations in the Ethiopian highland on soil fertility, shoot and root growth, nutrient utilisation and mycorrhizal colonisation. For Ecol Manag 61: 299-324. doi: 10.1016/0378-1127(93)90208-5
![]() |
[53] | Endale K (2011) Fertilizer Consumption and Agricultural Productivity in Ehiopia. Ethiopian Development Research Institute. |
[54] | Valentin CF, Agus R, Alamban A,et al. (2008) Runoff and sediment losses from 27 upland catchments in Southeast Asia: Impact of rapid land use changes and conservation practices. Agric Ecosyst Environ 128: 225-238. |
[55] |
Janeau JL, Gillard LC, Grellier S, et al. (2014) Soil erosion, dissolved organic carbon and nutrient losses under different land use systems in a small catchment in northern Vietnam. Agric Water Manag 146: 314-323. doi: 10.1016/j.agwat.2014.09.006
![]() |
[56] | Mailapalli DR, Burger M, Horwath WR, et al. (2013) Crop residue biomass effects on agricultural runoff. Appl Environ Soil Sci 2013: 805206. |
[57] |
Lisanework N, Michelsen A (1993) Allelopathy in agroforestry systems: the effect of Cupressus lusitanica and three Eucalyptus species on Ethiopian crops. Agrofor Syst 21: 63-74. doi: 10.1007/BF00704926
![]() |
[58] | Joshi M, Palanisami K (2011) Impact of eucalyptus plantations on ground water availability in South Karnataka. ICID 21st International Congress on Irrigation and Drainage. Tehran, Iran. |
[59] | Prabhakar VK (1998) Social and community forestry.Satish Garg. New Delhi. 90-106 |
[60] |
Lal R (2007) Anthropogenic influences on world soils and implications to global food security. Adv Agron 93: 69-93. doi: 10.1016/S0065-2113(06)93002-8
![]() |
[61] | Wiebe K (2003) Linking land quality, agricultural productivity, and food security. United States Department of Agriculture, Agricultural Economic Report Number 823. |
1. | Desalew Meseret Moges, Alexander Kmoch, H. Gangadhara Bhat, Evelyn Uuemaa, Future soil loss in highland Ethiopia under changing climate and land use, 2020, 20, 1436-3798, 10.1007/s10113-020-01617-6 | |
2. | Rameez Ahmad, Anzar A. Khuroo, Maroof Hamid, Irfan Rashid, Plant invasion alters the physico-chemical dynamics of soil system: insights from invasive Leucanthemum vulgare in the Indian Himalaya, 2019, 191, 0167-6369, 10.1007/s10661-019-7683-x | |
3. | Madelon Lohbeck, Leigh Winowiecki, Ermias Aynekulu, Clement Okia, Tor-Gunnar Vågen, Marney Isaac, Trait-based approaches for guiding the restoration of degraded agricultural landscapes in East Africa, 2018, 55, 00218901, 59, 10.1111/1365-2664.13017 | |
4. | Ayelech Kidie Mengesha, Reinfried Mansberger, Doris Damyanovic, Gernot Stoeglehner, Impact of Land Certification on Sustainable Land Use Practices: Case of Gozamin District, Ethiopia, 2019, 11, 2071-1050, 5551, 10.3390/su11205551 | |
5. | Maroof Hamid, Anzar Ahmad Khuroo, Akhtar Hussain Malik, Rameez Ahmad, Chandra Prakash Singh, Elevation and aspect determine the differences in soil properties and plant species diversity on Himalayan mountain summits, 2021, 36, 0912-3814, 340, 10.1111/1440-1703.12202 | |
6. | Travis W. Reynolds, Cathy D. Collins, Alemayehu Wassie, Janice Liang, Wilford Briggs, Margaret Lowman, Tizezew Shimekach Sisay, Endale Adamu, Sacred natural sites as mensurative fragmentation experiments in long-inhabited multifunctional landscapes, 2017, 40, 09067590, 144, 10.1111/ecog.02950 | |
7. | Priyanka Raja, Hema Achyuthan, K. Geethanjali, Pankaj Kumar, Sundeep Chopra, Late Pleistocene Paleoflood Deposits Identified by Grain Size Signatures, Parsons Valley Lake, Nilgiris, Tamil Nadu, 2018, 91, 0016-7622, 547, 10.1007/s12594-018-0903-0 | |
8. | Teowdroes Kassahun, Svane Bender, 2019, Chapter 12, 978-3-319-98680-7, 195, 10.1007/978-3-319-98681-4_12 | |
9. | Nathan S. Chesterman, Julia Entwistle, Matthew C. Chambers, Hsiao-Chin Liu, Arun Agrawal, Daniel G. Brown, The effects of trainings in soil and water conservation on farming practices, livelihoods, and land-use intensity in the Ethiopian highlands, 2019, 87, 02648377, 104051, 10.1016/j.landusepol.2019.104051 | |
10. | Solomon Ayele Tadesse, Demel Teketay, Determinant Factors Predicting the Dependencies of Local Communities on Plantation Forests and Their Levels of Participation on Management Activities in Basona Worena District, Ethiopia, 2020, 39, 1054-9811, 800, 10.1080/10549811.2020.1730907 | |
11. | Mesfin Sahle, Osamu Saito, Christine Fürst, Kumelachew Yeshitela, Quantification and mapping of the supply of and demand for carbon storage and sequestration service in woody biomass and soil to mitigate climate change in the socio-ecological environment, 2018, 624, 00489697, 342, 10.1016/j.scitotenv.2017.12.033 | |
12. | Solomon Ayele Tadesse, Solomon Mulu Tafere, Local people’s knowledge on the adverse impacts and their attitudes towards growing Eucalyptus woodlot in Gudo Beret Kebele, Basona Worena district, Ethiopia, 2017, 6, 2192-1709, 10.1186/s13717-017-0105-5 | |
13. | Amare Bitew Mekonnen, Distribution and ecological impact of exotic woody plant species inside sacred groves of Northwestern Ethiopia, 2019, 28, 0960-3115, 2845, 10.1007/s10531-019-01799-4 | |
14. | Arragaw Alemayehu, Woldeamlak Bewket, Trees and rural households’ adaptation to local environmental change in the central highlands of Ethiopia, 2018, 13, 1747-423X, 130, 10.1080/1747423X.2018.1465137 | |
15. | Yoseph T. Delelegn, Witoon Purahong, Amila Blazevic, Birru Yitaferu, Tesfaye Wubet, Hans Göransson, Douglas L. Godbold, Changes in land use alter soil quality and aggregate stability in the highlands of northern Ethiopia, 2017, 7, 2045-2322, 10.1038/s41598-017-14128-y | |
16. | Shiferaw Alem, Nesru Hassen, Mindaye Teshome, Kibruyesfa Sisay, Zelalem Teshager, Nesibu Yahya, Abeje Eshete, 2022, Chapter 8, 978-3-030-86625-9, 127, 10.1007/978-3-030-86626-6_8 | |
17. | Asabeneh Alemayehu, Yoseph Melka, Small scale eucalyptus cultivation and its socioeconomic impacts in Ethiopia: A review of practices and conditions, 2022, 8, 26667193, 100269, 10.1016/j.tfp.2022.100269 | |
18. | Svitlana Raspopina, Yuriy Debryniuk, Yuriy Hayda, Forest plantation productivity – soil interactions within Western Forest-Steppe of Ukraine: effects of pH and cations, 2020, 62, 2199-5907, 233, 10.2478/ffp-2020-0023 | |
19. | Ermias Debie, Mesfin Anteneh, Changes in Ecosystem Service Values in Response to the Planting of Eucalyptus and Acacia Species in the Gilgel Abay Watershed, Northwest Ethiopia, 2022, 15, 1940-0829, 194008292211089, 10.1177/19400829221108928 | |
20. | Eucalyptus plantation in Pakistan: Holistic View of Environmental-Socioeconomic and Medicinal Perspective, 2022, 8, 2410-955X, 41, 10.47262/BL/8.1.20211014 | |
21. | Avtar Singh, Pritpal Singh, G. P. S. Dhillon, Sandeep Sharma, Baljit Singh, R. I. S. Gill, Differential impacts of soil salinity and water logging on Eucalyptus growth and carbon sequestration under mulched vs. unmulched soils in south-western Punjab, India, 2023, 482, 0032-079X, 401, 10.1007/s11104-022-05700-1 | |
22. | Max Mallen‐Cooper, Joe Atkinson, Zoe A. Xirocostas, Baptiste Wijas, Giancarlo M. Chiarenza, Frederick A. Dadzie, David J. Eldridge, Global synthesis reveals strong multifaceted effects of eucalypts on soils, 2022, 31, 1466-822X, 1667, 10.1111/geb.13522 | |
23. | Mesfin Sahle, Osamu Saito, Travis W. Reynolds, Nature’s contributions to people from church forests in a fragmented tropical landscape in southern Ethiopia, 2021, 28, 23519894, e01671, 10.1016/j.gecco.2021.e01671 | |
24. | Debissa Lemessa, Befkadu Mewded, Abayneh Legesse, Hailu Atinfau, Sisay Alemu, Melese Maryo, Hailu Tilahun, Do Eucalyptus plantation forests support biodiversity conservation?, 2022, 523, 03781127, 120492, 10.1016/j.foreco.2022.120492 | |
25. | Mekonnen Amberber Degefu, Sileshi Degefa, Wondye Kebede, Debela Daba, Effect of complete abolition of Eucalyptus species on under canopy species diversity in Gullele Botanic Garden, Ethiopia, 2023, 26670100, 100701, 10.1016/j.envc.2023.100701 | |
26. | Sukanya Panikar, Ayyakannu Usha Raja Nanthini, Vidhya Rekha Umapathy, C. SumathiJones, Amitava Mukherjee, Palanisamy Prakash, Taimoor Hassan Farooq, Morphological, chemoprofile and soil analysis comparison of Corymbia citriodora (Hook.) K.D. Hill and L.A.S. Johnson along with the green synthesis of iron oxide nanoparticles, 2022, 34, 10183647, 102081, 10.1016/j.jksus.2022.102081 | |
27. | Paulina Guarderas, Kerly Trávez, Fanny Boeraeve, Jean-Thomas Cornelis, Marc Dufrêne, Native forest conversion alters soil macroinvertebrate diversity and soil quality in tropical mountain landscapes of northern Ecuador, 2022, 5, 2624-893X, 10.3389/ffgc.2022.959799 | |
28. | Bekele Bedada Damtie, Daniel Ayalew Mengistu, Daniel Kassahun Waktola, Derege Tsegaye Meshesha, Impacts of Soil and Water Conservation Practice on Soil Moisture in Debre Mewi and Sholit Watersheds, Abbay Basin, Ethiopia, 2022, 12, 2077-0472, 417, 10.3390/agriculture12030417 | |
29. | Kflay Gebrehiwot Yaynemsa, 2022, Chapter 8, 978-3-031-20224-7, 115, 10.1007/978-3-031-20225-4_8 | |
30. | Tiziana Danise, Walter S. Andriuzzi, Giovanna Battipaglia, Giacomo Certini, Georg Guggenberger, Michele Innangi, Giovanni Mastrolonardo, Francesco Niccoli, Francesco Pelleri, Antonietta Fioretto, Mixed-Species Plantation Effects on Soil Biological and Chemical Quality and Tree Growth of A Former Agricultural Land, 2021, 12, 1999-4907, 842, 10.3390/f12070842 | |
31. | Debissa Lemessa, Befkadu Mewded, Abayineh Legesse, Hailu Atinfau, Sisay Alemu, Melese Maryo, Hailu Tilahun, Do Eucalyptus Plantations Support Biodiversity Conservation?, 2022, 1556-5068, 10.2139/ssrn.4021674 | |
32. | Md. Abiar Rahman, Ashim Kumar Das, Zabid Al Riyadh, Md. Suhag, Md. Mezanur Rahman, Eucalyptus in Agriculture: Friend or Foe? Analyzing its impact on crop yields, soil dynamics, and farmers’ perceptions in Bangladesh, 2024, 0167-4366, 10.1007/s10457-024-01077-5 | |
33. | Degfie Teku, Abebaw Abebe, Melkamu Fetene, Ethiopian orthodox tewahedo church sacred forests as sanctuaries for endangered species: Key roles, challenges and prospects, 2024, 10, 2765-8511, 10.1080/27658511.2024.2391614 | |
34. | Rizki Maharani, Andrian Fernandes, Widya Fatriasari, 2024, Chapter 12, 978-981-99-7918-9, 185, 10.1007/978-981-99-7919-6_12 | |
35. | Abdurohman Yimam, Asnake Mekuriaw, Dessie Assefa, Woldeamlak Bewket, Claudio Cocozza, Effect of Eucalyptus globulus Plantations on Soil Physicochemical Properties in the Upper Blue Nile, Ethiopia, 2024, 2024, 1687-7675, 1, 10.1155/2024/8811109 | |
36. | Luth Mligo, Catherine A. Masao, Pius Z. Yanda, Impact of exotic plantation on native Grassland Biodiversity: A 30-Year analysis in Tanzania’s southern highlands, 2024, 79, 16171381, 126625, 10.1016/j.jnc.2024.126625 | |
37. | Ndidzulafhi Innocent Sinthumule, Sacred forests as repositories of local biodiversity in Africa: A systematic review, 2024, 2158-0103, 1, 10.1080/21580103.2024.2397522 | |
38. | Solomon Tadesse, Tekalign Assefa, Soil fertility status under different land uses and its management practices in Bure district of Ilu Ababor zone, southwest Ethiopia, 2024, 11, 2502-2458, 6099, 10.15243/jdmlm.2024.114.6099 | |
39. | Zahid Ahmed Mangral, Shahid Ul Islam, Lubna Tariq, Sharanjeet Kaur, Rameez Ahmad, Akhtar H. Malik, Shailendra Goel, Ratul Baishya, Saroj Kanta Barik, Tanvir Ul Hassan Dar, Altitudinal gradient drives significant changes in soil physico-chemical and eco-physiological properties of Rhododendron anthopogon: a case study from Himalaya, 2023, 6, 2624-893X, 10.3389/ffgc.2023.1181299 | |
40. | Elias Bojago, Mesele Woldemichael Delango, Daniel Milkias, Effects of soil and water conservation practices and landscape position on soil physicochemical properties in Anuwa watershed, Southern Ethiopia, 2023, 14, 26661543, 100705, 10.1016/j.jafr.2023.100705 | |
41. | Michael F. Nagle, Surbhi S. Nahata, Bahiya Zahl, Alexa Niño de Rivera, Xavier V. Tacker, Estefania Elorriaga, Cathleen Ma, Greg S. Goralogia, Amy L. Klocko, Michael Gordon, Sonali Joshi, Steven H. Strauss, Knockout of floral and meiosis genes using CRISPR/Cas9 produces male‐sterility in Eucalyptus without impacts on vegetative growth, 2023, 7, 2475-4455, 10.1002/pld3.507 | |
42. | Wesley M. Zebrowski, Travis W. Reynolds, Consumed from within? Social and ecological drivers of internal clearings in Ethiopian Orthodox church forests, 2024, 35, 1085-3278, 334, 10.1002/ldr.4919 | |
43. | Olivier Niyompuhwe, Charbel Maklouf Jabiro, Canisius Patrick Mugunga, Effects of Eucalyptus species on soil physicochemical properties in Ruhande Arboretum, Rwanda, 2023, 2466-4367, 43, 10.21750/REFOR.16.04.109 | |
44. | Ceyhun GÖL, Meliha ÇİÇEK, The Investigation of Some Soil and Morphological Properties of Trees in Conversion of Marsh into Eucalyptus camaldulensis (Dehn) Different Ages Plantation, (Mediterranean Region – Turkey), 2019, 19, 1303-2399, 197, 10.17475/kastorman.625684 | |
45. | Teresa Cochrane, Gaye L. Krebs, Scott McManus, Scott Castle, Peter G. Spooner, Paul Cooper, Effect of soil treatment on the growth and foliage chemistry of three Eucalyptus species grown in a plantation as a food source for koalas, 2023, 71, 0004-959X, 10.1071/ZO22046 | |
46. | Dilnesa Bayle, Anna Źróbek-Sokolnik, Impacts of Land Use Types and Soil Depth on Soil Fertility Status in Dende Kebele, West Gojjam Zone, Ethiopia, 2024, 2024, 1687-9368, 10.1155/ijfr/8982548 | |
47. | Neha Thapliyal, Puja Bhojak, K. Chandra Sekar, Kapil Bisht, Poonam Mehta, Dhani Arya, Sunil Joshi, Potential drivers of plant diversity and composition in high-altitude alpine regions of Himalaya, 2024, 1585-8553, 10.1007/s42974-024-00224-3 | |
48. | Adrián Lázaro‐Lobo, Romina D. Fernandez, Álvaro Alonso, Paula Cruces, Verónica Cruz‐Alonso, Gary N. Ervin, Antonio Gallardo, Elena Granda, Daniel Gómez‐Gras, Hélia Marchante, Daniel Moreno‐Fernández, Asunción Saldaña, Joaquim S. Silva, Pilar Castro‐Díez, Worldwide comparison of carbon stocks and fluxes between native and non‐native forests, 2024, 1464-7931, 10.1111/brv.13176 | |
49. | Fasika Belay, Messay Mulugeta, Teferee Makonnen, Eucalyptus-based livelihoods: enhancing household food security and resilience in Northwest Ethiopia, 2025, 9, 2571-581X, 10.3389/fsufs.2025.1496756 | |
50. | Getinet Masresha, Worku Misganaw, Abiyu Enyew, Comparative analyses of the conservation status of forest patches in the northwestern region of Ethiopia, 2025, 1472-8028, 1, 10.1080/14728028.2025.2482644 |