Natural Forest Land Research Articles

Soil carbon sequestration potential of different land use systems: evidence from sub-humid southern plains and Aravalli hills of Rajasthan, India.

This study has assessed total soil organic carbon (TOC) fractions, carbon management index (CMI), and carbon sequestration economic value under diverse land use systems (LUSs) of sub-humid Southern plains of Rajasthan, India. The study dealt with six LUSs: barren land (BL), agricultural land (AL), agri-horticulture (AH), horticultural land (HL), grassland (GL), and natural forest land (FL) were selected for the study. FL contained the highest TOC (13.04 ± 0.74gkg-1), particulate organic carbon (POC) (2.2 ± 0.19gkg-1), mineral-associated organic carbon (MAC) (10.84 ± 0.54gkg-1), and CMI (230.36 ± 4.13), whereas BL had the lowest amount of TOC (3.53 ± 0.4gkg-1), POC (0.47 ± 0.06gkg-1), MAC (3.06 ± 0.32gkg-1), and CMI (54.60 ± 4.2). The impact of LUSs on soil carbon lability index (LI) was minimal in all LUSs except FL exhibited statistically insignificant variations in LI. TOC stock showed the highest decline in BL (71.04%), AL (55.29%), AH (44.38%), and HL (25.92%) uses compared with the FL system. Different LUSs result in varying amounts of carbon stocks, representing the relative carbon credit gain. The maximum carbon credit was achieved by FL, which was roughly US $49,303 and 245% higher than BL. These results indicate the reinstatement of BL and AL towards HL and AH systems, and effective recycling of residues could improve the TOC storage in the study region.

Climate Profile Over Jeldu Woreda of West Shewa Zone, Oromia, Ethiopia

Identifying the climate profile of an area is essential for effective water resource management, agricultural planning and disaster preparedness. This study focuses on characterizing rainfall patterns and identifying the variability of Jeldu woreda in Oromia, Ethiopia. Previously and recently, little study tried to show the woreda profile, which did not bases on station data properly. Forty years (1981-2020) of stations’ rainfall and temperature data were utilized. The study area had natural forest, highland and mid land with varying topography. Based on the annual rainfall cycle, the woreda had bi-modal rainfall types, with the peak of the year being July. Statistical methods and python script were applied to identify the climate profile. The results show that main rainy seasonal rainfall starts on average from 12-14 June and ceases averagely around 10-15 October. During second rainy period, the rain starts from 25 February to 10 March. The mean annual rainfall of woreda is 1395.1 mm, and the average maximum temperature is 19.5°. Kiremt contributes the highest percent, which is more than 64 % of the annual total rainfall. The 1987 and 2015 were the driest years, and 1996 and 2010 is the wettest during kiremt, 1987 and 2010 the wettest, and 1999 and 2015 the driest during Belg. Seasonal rainfall had a regular to moderate precipitation concentration over woreda. Identifying the causes of unseasonal rainfall that happened during dry season over the study area can help to decrease weather hazard during the season.

Heavy metal changes related to land use changes in a karst area: a case study in Changshun, Guizhou Province, China

Karst areas are often characterized by fragile ecological systems, and environmental pollution has increased the pressures on people living in such regions. This study aimed to investigate the status of pollution caused by heavy metals (Pb, Cd, Hg, As, and Cu) in soils based on different land uses in Changshun County, a karst area in southwestern China. Soil samples were collected from natural forestlands (NFLs), natural brush lands (NBLs), natural pasture lands (NPLs), artificial forestlands (AFLs), artificial brush lands (ABLs), and artificial pasture lands (APLs) for evaluation. The results suggest that the soil profile characteristics of the heavy metals studied herein vary significantly among different land uses. The heavy metal concentrations in all soil samples collected from NFLs were lower than those in samples from other land uses. Forest trees can protect soil from heavy metal pollution caused by atmospheric deposition; this is especially true for Hg. In cultivated forestlands and brush lands, special attention should be devoted to Cd pollution in the soil, which may be caused by the use of fertilizers. Changing both natural and artificial pastoral lands to forestlands could benefit the local ecosystems as it may reduce Hg contamination.

Assessing sediment CO2 effluxes in the coastal ecosystem of North Sumatra, Indonesia

Coastal wetlands including mangrove play a vital role in regulating the local and global carbon cycle. Coastal areas contribute greatly to the carbon exchange process due to the complex interactions that occur between the atmosphere, land, and oceans. One of the important components in coastal carbon dynamics is CO2 gas exchange between soil, water and the atmosphere. This study aims to assess CO2 efflux across various land covers (namely natural mangrove, restored mangrove, and converted mangroves to oil palm and aquaculture pond) in the coastal areas of North Sumatra Province, and analyze the effect of sea tides and ebbs on the rate of CO2 efflux and their connection with the number and area of macrozoobenthos burrows. We applied direct sampling by using the static closed chamber method attached to portable CO2 analyzer. The mean of CO2 efflux in natural mangrove forest land covers was 866±585 mgCO2/m2/h during low tide conditions and 1137±792 mgCO2/m2/h during high tide conditions, followed by oil palm plantations at 760.71±341 mgCO2/m2/h, restored mangroves during low tide of 575.24±326 mgCO2/m2/h and 597.11±180 mg CO2/m2/h during high tide conditions, and the lowest was recorded in ponds at 588.55±358 mgCO2/m2/h. Further, we observed that tidal conditions affect the magnitudes of CO2 efflux in natural and restored mangrove forests, and we did not observe similar pattern in oil palms and ponds since these land covers were not influenced by regular tidal input. We also observed that no significant relationship between the number and area of macrozoobenthos burrows and CO2 efflux. Our findings suggest that CO2 effluxes in coastal wetlands are highly dynamic and presumably driven by complex factors and therefore, understanding their magnitudes and drivers requires extensive measurement covering large spatial and temporal scales.

Spatiotemporal characteristics and multi-scenario simulation of land use change and ecological security in the mountainous areas: Implications for supporting sustainable land management and ecological planning

The acceleration of global urbanization has intensified land use activities, which threaten the ecological environment and hinder the achievement of sustainable socioeconomic development goals. With the background of continuous land use expansion, the reasonable management of land use and ecological protection has increasingly become an important issue. This study constructs an ecological security (ES) index to evaluate the ES pattern, and employs the Future Land-Use Simulation (FLUS) model for multi-scenario simulation of land use patterns in mountainous areas. The results showed that from 2000 to 2020, cultivated land and grassland showed a sharp decrease, with areas of −128.64 and −228.18 km² respectively, while forest land, urban land, and other construction land increased, with areas of 116.12, 31.21, and 120.69 km² respectively. Over time, the mountainous areas mainly exhibited low and moderate ES patterns. Furthermore, for 2020–2030, under the natural development scenario, cultivated land, forest land, and grassland will show a decrease, while urban and other construction land will show a sharp increase. In contrast, under the ecological protection scenario, ecological land will show significant increase, and the patch expansion of urban construction land will be smaller. These results confirm the positive contribution of ES protection effects to improving the land use development, and support insightful guidance for formulating policies on ecological management in mountainous areas.

Soil mycobiomes in native European aspen forests and hybrid aspen plantations have a similar fungal richness but different compositions, mainly driven by edaphic and floristic factors.

The cultivation of short-rotation tree species on non-forest land is increasing due to the growing demand for woody biomass for the future bioeconomy and to mitigate climate change impacts. However, forest plantations are often seen as a trade-off between climate benefits and low biodiversity. The diversity and composition of soil fungal biota in plantations of hybrid aspen, one of the most planted tree species for short-rotation forestry in Northern Europe, are poorly studied. The goal of this study was to obtain baseline knowledge about the soil fungal biota and the edaphic, floristic and management factors that drive fungal richness and communities in 18-year-old hybrid aspen plantations on former agricultural soils and compare the fungal biota with those of European aspen stands on native forest land in a 130-year chronosequence. Sites were categorized as hybrid aspen (17-18-year-old plantations) and native aspen stands of three age classes (8-29, 30-55, and 65-131-year-old stands). High-throughput sequencing was applied to soil samples to investigate fungal diversity and assemblages. Native aspen forests showed a higher ectomycorrhizal (EcM) fungal OTU richness than plantations, regardless of forest age. Short-distance type EcM genera dominated in both plantations and forests. The richness of saprotrophic fungi was similar between native forest and plantation sites and was highest in the middle-aged class (30-55-year-old stands) in the native aspen stands. The fungal communities of native forests and plantations were significantly different. Community composition varied more, and the natural forest sites were more diverse than the relatively homogeneous plantations. Soil pH was the best explanatory variable to describe soil fungal communities in hybrid aspen stands. Soil fungal community composition did not show any clear patterns between the age classes of native aspen stands. We conclude that edaphic factors are more important in describing fungal communities in both native aspen forest sites and hybrid aspen plantation sites than forest thinning, age, or former land use for plantations. Although first-generation hybrid aspen plantations and native forests are similar in overall fungal diversity, their taxonomic and functional composition is strikingly different. Therefore, hybrid aspen plantations can be used to reduce felling pressure on native forests; however, our knowledge is still insufficient to conclude that plantations could replace native aspen forests from the soil biodiversity perspective.

The transition from shifting cultivation to indigenous agroforestry as nature-based solution for land restoration in the Indian Eastern Himalayas

In the Indian Eastern Himalayas, shifting cultivation has long been a major cause of land degradation. However, indigenous communities, like the Hmar, have successfully transitioned from shifting cultivation to agroforestry systems such as pineapple agroforestry, leading to land restoration and increased household incomes. Despite these positive outcomes, little is known about how soil health indicators change during this transition. Thus, the present study aimed to investigate changes in selected soil health indicators and erodibility across different age classes of pineapple agroforestry systems (<5, 5–10, 11–15, and > 15 years old) compared to shifting cultivation and nearby natural forests. Soil samples were collected from six sites, including different stages of pineapple agroforestry systems, shifting cultivation phases, and a natural forest. At each site, three (10 × 10 m) quadrats were selected, and two (1 × 1 × 1 m) vertical soil pits were dug in each quadrat, sampling soil depths from 0 to 100 cm. The transition from shifting cultivation to pineapple agroforestry improved soil organic carbon (SOC) and stratification ratios while reducing soil erodibility. SOC stocks were estimated at 182.7 Mg C/ha for natural forest land and 188.2 Mg C/ha for the cropping phase in shifting cultivation. On the other hand, estimated SOC stocks for < 5, 5–10, 11–15 and > 15 years old stands of pineapple agroforestry system were 169.7 Mg C/ha, 157.2 Mg C/ha, 168.9 Mg C/ha and 177 Mg C/ha respectively. Thus, the estimated SOC stocks under > 15 years of pineapple agroforestry were comparable with adjacent natural forest land. The stratification ratios (SR > 2) for SOC and macronutrients indicated better soil quality in the pineapple agroforestry system than in the cropped land. The clay and modified clay ratios decreased with increasing age of pineapple agroforestry stands. The highest clay ratio was recorded in the topsoil of < 5-year-old pineapple agroforestry system, indicating a greater risk of exposure to rainfall events than in natural forest land and the cropping phase in the shifting cultivation cycle. It is concluded that transitioning from shifting cultivation to a pineapple agroforestry is a nature-based solution to restore degraded lands and presents an excellent opportunity for sustainable soil health and carbon sink management.

Changes in natural forest land cover of the Eucalyptus urophylla type in the Mutis Timau area in 2002-2022, East Nusa Tenggara Province

Anthropogenic activities carried out by communities around forests in production forests, protected forests, and conservation forests have an impact on changes in the land cover of these areas. This impact is difficult to avoid because, on the other hand, production forests and protected forests are in direct contact with the lives of local communities. Changes in land cover have a significant impact on the contribution of Folu Net Sink, which is set by the government at 31.89% in 2030 with its efforts. This research aims to provide an overview of land cover changes that occurred in natural forests of the Eucalyptus urophylla type from 2002 to 2022. The method used in this research is a supervised/guided digital classification technique. Ground checks were also carried out in this research to match the accuracy of the image data with the actual conditions in the field. The research results show that changes in land cover in 2012 and 2017 were very extreme. Forest fires were the cause of changes in land cover during this period. Meanwhile, in 2002, 2007, and 2022, the land cover was still good, in a positive direction. The causes of changes in land cover are encroachment activities, encroachment, illegal logging, firewood theft, rice fields, forest fires, plantations, and farming. Forest preservation provides very high benefits for life on earth. Therefore, it is important to pay attention to the welfare of local communities so that they do not damage the forest, as well as increase the capacity to educate the community regarding zoning or blocks in conservation and protected forests. Apart from that, good forest management is needed to ensure forest sustainability in the future.

Soil Properties Variation Valued in Relation to Land Use and Management Practices in Vietnam

Background: Land use and management practices (LUMPs) have been accelerated globally to serve the increasing socio-economic requirements in recent decades. Methods: This study focuses to assess the impacts of the LUMPs on the properties and composition of soil in the Lam River Basin (LRB), Vietnam based on analysis of ninety-six soil samples collected in the soil profiles (0_60 cm). Result: The results indicated that the sand and clay ratios (34.0~35.7% and 16.2~19.9%) and bulk density (BD) (1.07±0.05~1.34 ± 0.06 Mg m-3) in the natural forest lands (NFLs) were lower and higher perturbed than the plantation forest lands (PFLs) (31.1~ 51.5%, 5.7~38.2% and 0.86 ± 0.03~1.12±0.05 Mg m-3) in the 0-20 cm topsoil layer. The soil texture is mainly sandy clay to clay loam and the BD tends slightly increase in the topsoil layer, then decrease in the 20-60 cm subsoil layer. There is no difference in soil pH between collected soil samples (CSSs) and tends to increase with increasing the subsoil layer. The base cations (BCs) (Ca2+, K+, Mg2+: 0.01~0.29, 0.06~0.11 and 0.06~0.07 Cmolc kg-1) and total organic contents (TOCs) (total carbon (TC), total nitrogen (TN), total phosphorus (TP): 24.11; 2.80 and 0.19 g kg-1) of the NFLs are higher than those of the CSSs (TC, TN, TP: 14.37~23.91, 1.62~2.28 and 0.08~0.17 g kg-1) in the topsoil layer while these values were not different in the topsoil layer.

Preface

4th International Interdisciplinary Conference on Green Development in Tropical Regions (4th IICGDTR) “Governance Challenges of Green Development in Tropical Asia” Virtual Conference The Graduate Program – Universitas Andalas, West Sumatera, Indonesia 7 – 8 July 2021 The 4th International Interdisciplinary Conference on Green Development in Tropical Regions (4th IICGDTR) has successfully held virtually on 7 – 8 July 2021 organized by the Graduate Program, Universitas Andalas, West Sumatera, Indonesia.IICGDTR is the biannual international conference on Green Development in Tropical Region (ICGDTR). This 2021 conference is the 4th interdisciplinary ICGDTR which held virtually due to the covid-19 pandemic, with the theme “Governance Challenges of Green Development in Tropical Asia”. The main objective of this international conference is to enhance the discourse and discussion on various aspects of green development in tropical regions, especially on the issue of governance challenges of green development in tropical regions.Since the early 21st century, conventional development strategies have been questioned by various development analysts, especially those concerned with issues and conflicts surrounding its environmental, human and socio-economic impacts. The debate on issues surrounding degradation of natural resources, forest, coastal, and agricultural land, along with understanding climate change, has led to the new proposition of the green development paradigm. The conceptual understanding of the green development paradigm is concerned with the strategy and planning of all aspects including environmental planning, rural and urban planning, regional development planning, agriculture and industrial development planning.The tropical region of Asia, covering South, Southeast, and part of East Asia, is a region with a large population, rich biodiversity, and also high growth. More importantly, this is a culturally rich region. Tropical Region of Asia (TRA) is the most dynamic region and is in a constant effort to balance its development path. Much of the region’s economic growth is supported by the exploitation of common-pool natural resources, i.e., forest, land, water. Agriculture is still a dominant livelihood strategy with very slow technological adoption. But the region also utilizes its ecosystem services for the tourism sector to diversify livelihood. Rural and urban development is still not balanced but instead is urban biased. Unfortunately, housing and settlement development in urban areas sometimes threatens agricultural land.List of Committee is available in this Pdf.

ANALISIS EVALUASI EKONOMI SUMBER DAYA ALAM DAN LINGKUNGAN DI KABUPATEN KONAWE SELATAN

The condition of natural resources of forests and agricultural land, especially in South Konawe Regency, is currently quite a concern. South Konawe Regency has a forest area with a total area of 475,953 hectares, consisting of natural reserve forests, protected forests, production forests, limited production forests, other use areas, water bodies, community plantation forests, urban forests, mangrove forests and conservation forests. Among the total current forest area, there are 31,874 hectares of critical land and 6,606 hectares of very critical land. The aim of the research is to inventory the potential and management problems as well as the economic value of natural forest and agricultural land resources in South Konawe Regency. The research approach uses 5 (five) approach models, namely the political approach, the technocratic approach, the integrated top-down policy bottom-up planning approach, the participatory approach, and the regional finance approach. The type of research used in this research is qualitative research with a case study method. Research data needs were collected using questionnaires and field surveys. The data analysis methods used include Natural Resource Potential Analysis, Identification of natural resources in forests and agricultural land, as well as total economic analysis or total economic value (TEV) obtained from the sum of values based on use and values based on indirect use. The research results show that the potential forest resources of South Konawe Regency with samples from Wolasi, Laeya, and Tinanggea subdistricts are divided into 4 forest area function classes, namely protected forests, permanent production forests, limited production forests, and national parks. Protected forests covering an area of 11,273.58 ha, limited production forests covering an area of 2,860.99 ha, permanent production forests covering an area of 14,931.17 ha, and national parks covering an area of 9,246.96 ha. Meanwhile, the agricultural potential of South Konawe Regency from the research sample consists of mixed dry land farming covering an area of 14,787.73 ha, dry land farming covering an area of 1,684.39 ha, rice fields covering an area of 17,014.23 ha, and plantations covering an area of 553.44 ha. The economic value of South Konawe district's forest resources is IDR 64,152,630,168.15 per year, while the economic value of agricultural land resources is IDR 9,342,541,716/year.

Effects of afforestation and upslope distance on soil moisture and organic carbon, and trade-off between them, on the Loess Plateau hillslopes

Large-scale afforestation is considered controversial as an ecosystem renewal strategy for the Loess Plateau of China, since it may increase soil organic carbon (SOC) but may also exacerbate water shortages. In our study, we aimed to clarify how afforestation and slope affect soil moisture content (SMC) and SOC and their interaction particularly for deep hillslope profiles on long hillslopes, in terms of the trade-off between soil moisture and organic carbon. This study investigated SMC and SOC density (SOCD) from 0 to 400 cm hillslope depth profiles at 20 m intervals uphill to 100 m in the May and October (the beginning and end of the growing period, respectively) from 2015 to 2017. The three sampling sites were located in Robinia pseudoacacia plantation, natural forest, and natural grassland as the control. Soil moisture deficit and SOC sequestration of plantation were compared to those of grassland, and the trade-off between SMC and SOCD was evaluated. The results showed that SMC and SOCD were the lowest in the Robinia pseudoacacia plantation, indicating that the plantation exhibited a greater soil moisture deficit and SOC loss than the grassland. In the plantation and natural forestland, the subsoil (100–400 cm) exhibited greater soil moisture deficit and SOC loss than the soil (0–100 cm). SOCD increased while SMC decreased with upslope distance for all hillslope layers in both plantation and natural forestland. The downslope sites exhibited more severe soil moisture deficit, and greater SOC loss than the upslope sites. Natural grassland exhibited low water depletion and high SOC sequestration. Further, the downslope plantation sites exhibited the lowest root mean square deviation for the relationship between SMC and SOCD. Based on these findings, a vegetation restoration strategy involving afforestation of downslope patches within a contiguous grassland matrix may achieve high-level maintenance of ecosystem services. These findings provide a theoretical basis for vegetation restoration on the Loess Plateau.

Altered landscape pattern dominates the declined urban evapotranspiration trend

Urbanization has significantly altered the regional hydrological cycle and thermal environment. However, the response of urban evapotranspiration (ETu) to these altered urban landscape patterns remains unclear. This study proposes a hybrid ETu model that combines physics processes and machine learning to evaluate trends and drivers of ETu across 480 cities in China. The results indicate that the long-term average ETu across the 480 cities is 508 mm, and the average rate of decline in ETu (DRETu) across the 480 cities is 2.19 mm/year. DRETu exhibits a positive correlation with the increasing rate of urban aridity index (AI) and fractional impermeable surface coverage (fi). The decrease in ETu is primarily caused by the altered urban landscape patterns, which include: 1) reductions in urban vegetation and water body areas resulting from urbanization; and 2) the substitution of natural forest land with landscape grasslands in urban areas. We further investigated the correlation between the urban heat island (UHI) effect and ETu and found that the intensified UHI effect is caused by an increased difference in ETu between the main urban area and the suburbs. The results of this study emphasize the significance of constructing water bodies and green infrastructure in the central urban area, as well as restoring natural forests, to enhance the thermal comfort of the urban environment.

Distribution of Carbon Stocks under Different Land Use Systems of Somawarpet Taluk, Kodagu District, India

A study was conducted in Somawarpet taluk of Kodagu district in Karnataka in the aim the soil carbon stocks under different land use systems namely natural forest land use, coffee based agroforestry and paddy systems. Soil samples were collected at different depths like 0-20, 20-40, 40-60 and 60-80 cm with five replications under each land use systems. Natural Forest showed the highest mean value of Potassium Dichromate Oxidizable Carbon content of 18.06g kg-1, followed by coffee system with o Potassium Dichromate Oxidizable Carbon content of 13.86 g kg-1 and the lowest mean value (8.23 g kg-1) was found in paddy land use system. The highest mean value of bulk density (BD) was found in paddy land use system (1.33 Mg m-3). In all the land use systems BD content increases with increasing soil depth. The highest soil carbon stock mean value of 4140.23 t ha-1 was noticed in natural forest, followed by coffee land use system (3267.38 t ha-1) and lowest value of 2171.45 t ha-1 of carbon stock content was observed under paddy land use system. In all the land use systems Potassium Dichromate Oxidizable Carbon content and carbon stock content was decreasing with increasing soil depth.

A Chronicle of Indonesia’s Forest Management: A Long Step towards Environmental Sustainability and Community Welfare

Indonesia is the largest archipelagic country in the world, with 17,000 islands of varying sizes and elevations, from lowlands to very high mountains, stretching more than 5000 km eastward from Sabang in Aceh to Merauke in Papua. Although occupying only 1.3% of the world’s land area, Indonesia possesses the third-largest rainforest and the second-highest level of biodiversity, with very high species diversity and endemism. However, during the last two decades, Indonesia has been known as a country with a high level of deforestation, a producer of smoke from burning forests and land, and a producer of carbon emissions. The aim of this paper is to review the environmental history and the long process of Indonesian forest management towards achieving environmental sustainability and community welfare. To do this, we analyze the milestones of Indonesian forest management history, present and future challenges, and provide strategic recommendations toward a viable Sustainable Forest Management (SFM) system. Our review showed that the history of forestry management in Indonesia has evolved through a long process, especially related to contestation over the control of natural resources and supporting policies and regulations. During the process, many efforts have been applied to reduce the deforestation rate, such as a moratorium on permitting primary natural forest and peat land, land rehabilitation and soil conservation, environmental protection, and other significant regulations. Therefore, these efforts should be maintained and improved continuously in the future due to their significant positive impacts on a variety of forest areas toward the achievement of viable SFM. Finally, we conclude that the Indonesian government has struggled to formulate sustainable forest management policies that balance economic, ecological, and social needs, among others, through developing and implementing social forestry instruments, developing and implementing human resource capacity, increasing community literacy, strengthening forest governance by eliminating ambiguity and overlapping regulations, simplification of bureaucracy, revitalization of traditional wisdom, and fair law enforcement.

The Extension and Improvement of the Forest Land Net Present Value Model and Its Application in the Asset Evaluation of Cunninghamia lanceolata Forest Land

In order to solve the problem in that the classical forest land expectation value method ignores the actual forest stock volume when assessing the income at the end of the current production cycle in the forest, and fill the research gap in this area, the technical system of the forest land asset evaluation was enriched. The forest land returns were divided into two parts, i.e., the segmented forest land return price from the growth of the actual forest stand to the end of the growth cycle (Bu1), and the segmented forest land return price for an infinite number of growth cycles after the growth of the actual forest stand to the end of the growth cycle (Bu2). Through structure, the forest land gain price expansion model was obtained, and the stand quality including the average diameter at breast height, average height, stock volume, and outturn of stand as dummy variables were used to construct the growth harvest model related to asset evaluation. Taking Cunninghamia lanceolata forest land as an example, the traditional asset evaluation methods were comparatively analyzed. The residual standard deviation (RSD) of the growth model was less than 10%, the total relative error (TRE) and mean system error (MSE) were within ±10%, the mean prediction errors (MPE) were less than 5%, and the mean percentage standard errors (MPSE) were less than 10%, respectively. Combining the forest land net present value expansion model with the traditional evaluation method, the evaluation value of the forest land assets was subsequently calculated, and accordingly, the forest land asset evaluation prime stand factors were predicated. It was found that the valuation results of the forest land net present value expansion model were consistent with the actual situation. The forest land net present value expansion model can therefore be used for asset evaluation of tree forest land (including natural uneven-aged forest land), bamboo forest land, shrub forest land, and economic forest land, and provide new technical support for forest land asset evaluation.

The Landscape Characteristics Analysis of Rawa Bunder Resort at Park National Way Kambas

The importance of research on the Rawa Bunder Resort’s landscape characteristics at Way Kambas National Park (WKPN) is as a basis for area management according to its function in a lowland tropical rain forest ecosystem. The purpose of this study is to find out the current characteristics of landscape include physical and biological characteristics as well as the driving factors for the establishment of good habitat restoration for flora and fauna life. The results showed that the landscape characteristics of the Rawa Bunder Resort consisted of natural forest and open land containing shrubs with almost the same area composition. The position of the forest appears to be united in the middle to the east of the WKNP. The pressure of Imperata fires can threat the existence of forests. If the preventive action is not taken immediately, the forest will decrease in size. The driving factor for the reduction of the forest matrix is ​​the frequent occurrence of forest fires every year. These fires were triggered by humans who intentionally or unintentionally driven by the wind so that it spread widely.

Some physical properties of a sandy clay loam humic soil under native forest and sugarcane in northern KwaZulu-Natal, South Africa

The conversion of native forest land to commercial farming can have profound effects on soil physical properties. This study compared bulk density (BD), saturated hydraulic conductivity (Ks) and other physical properties of a sandy loam humic soil under native forest and sugarcane fields in northern KwaZulu-Natal. Three plots (approximately 0.1 to 0.3 ha) were demarcated at each site. Ten composite soil and core samples were collected in each plot at intervals of 0.05 m in the 0–0.2 m, 0.1 m in the 0.2–0.6 m and 0.2 m in the 0.6–1.0 m depths and analysed using standard methods. In total, 60 composite and core samples were collected from both sites. Overall, BD was higher under forest (1 410 kg m−3) than sugarcane (1360 kg m−3) while the Ks was higher under sugarcane (310 mm h−1) than forest (260 mm h−1). The Ks correlated positively with sand at 0–0.3 and 0–1.0 m depths. The results suggest that long term (30 years) sugarcane cultivation has the capacity to decrease BD while improving Ks of the studied soils, making the crop more beneficial on water movement characteristics especially in the drought-prone Zululand region of South Africa.

The effect of land use type on selected soil physicochemical properties in Shihatig watershed, Dabat district, Northwest Ethiopia

Different land use practices have a substantial influence on soil quality. An inappropriate land use system in Ethiopia leads to extensive deforestation which aggravates the loss of soil fertility. Even though there are various studies conducted on the effect of land use type on soil physicochemical properties, it is inadequate in the northern highlands of Ethiopia, in particular in the Dabat district. Thus, this study aimed to assess the effect of land use type and soil depth on selected soil physicochemical properties in the Shihatig watershed, Northwest Ethiopia. A total of 24 undisturbed core and disturbed composite soil samples were collected from the four land use types (natural forest, grazing, cultivated, and Eucalyptus lands) and two depths (0–20 cm and 20–40 cm) with three replications. The physicochemical properties of the soil were determined using standard operating procedures. The two-way analysis of variances was conducted using SAS software, Version 9.4. The result showed that the texture and soil organic carbon were affected by land use type, soil depth, and the interaction of the two factors; while bulk density, soil moisture content, total nitrogen, available phosphorus, cation exchange capacity, and level of Mg2+ were significantly affected by both land use and soil depth, whereas pH and electrical conductivity were affected by only the land use type. The highest clay, pH, electrical conductivity, total nitrogen, cation exchange capacity, and exchangeable cations (Ca2+ and Mg2+) were recorded in the natural forest land, while the lowest values of the same parameters were found under cultivated land. The mean values of most of the soil properties were low in the cultivated and Eucalyptus lands. Therefore, adopting sustainable cropping systems such as crop rotation and the addition of organic manure, and minimizing planting the Eucalyptus tree is vital to improve the existing soil quality and enhance crop productivity.

Determination of nitrogen sources and losses in surface runoff from different lands at a watershed scale.

Nitrogen (N) loss by surface runoff inevitably results in severe N pollution and eutrophication of aquatic ecosystems. In this study, surface runoff from different land uses in the East Tiaoxi River watershed was collected, and the N concentrations, sources and losses were measured using the dual isotope (δ15N-NO3- and δ18O-NO3-), a Bayesian isotopic mixing (SIAR) model and Soil Conservation Service Curve Number (SCS-CN) method. The results showed that the N concentrations in surface runoff from agricultural lands were higher than those from urban areas and forestlands, and nitrate (NO3-), particulate nitrogen (PN) and dissolved organic nitrogen (DON) were the major forms of N in surface runoff in the East Tiaoxi River watershed. The total loss rate of total nitrogen (TN) from surface runoff in the East Tiaoxi River watershed was 5.38kg·ha-1·a-1, with NO3--N (46%) contributing the most to TN loss. The TN, and NO3--N loss rates in surface runoff from tea planting lands (21.08kg·ha-1·a-1, 11.98kg·ha-1·a-1) and croplands (16.93kg·ha-1·a-1, 10.96kg·ha-1·a-1) were high, those from vegetable lands and urban areas were medium, and those from economic and natural forestlands were low in the East Tiaoxi River watershed. The NO3--N contributions of chemical fertiliser (CF), soil N (SN), sewage/manure (SM), and atmospheric deposition (AD) in surface runoff in the East Tiaoxi River watershed were 124.32 × 103, 104.84 × 103, 82.25 × 103 and 58.69 × 103kg·a-1, respectively. The N pollutant losses in surface runoff from agricultural lands (croplands with rice growing, vegetable lands and tea planting lands) were responsible for most of the N pollutants being transported into the East Tiaoxi River systems.