Impact of intensive agricultural management on carbon and nitrogen dynamics in the humid tropics     

Benito Heru Purwanto  Syamsu Alam 《Soil Science and Plant Nutrition》2020,66(1):50-59

ABSTRACT

The concern about global climate change continues to increase research interest regarding carbon and nitrogen dynamics in the soil. This is based on their role in maintaining soil fertility, which can instead be a source of greenhouse gas emissions if not managed properly, while threatening food security. Humid tropical conditions enable intensive agricultural cultivation with various cropping systems to fulfill the demand for agriculture products. Such climate accelerates the soil organic matter decomposition rate so that it strongly influences soil carbon and nitrogen dynamics. However, inappropriate implementation of intensive agricultural systems that does not consider the balance between carbon and nitrogen input and output, negatively affects soil fertility, mainly decreasing soil organic carbon and total soil nitrogen, changing the composition of carbon and nitrogen owing to the loss of soil organic matter through erosion and leaching, thus, causing soil degradation. Mitigation strategies can be performed by using organic matter and crop residue, crop rotation and improvement of crop pattern, soil tillage and fertilization, cover crops and mulch. Sustainable land management for maintenance of soil organic carbon and total soil nitrogen dynamics should be locally and globally developed and adopted for a more sustainable agricultural system. Recovery of soil capacity to accumulate carbon is a strategic step to reduce the impact of climate change. Hence, an intensive study on efficient soil organic carbon management is required to improve food production and mitigation of climate change to attain sustainable development goals in 2030.  相似文献   

Homestead forest resources and their role in household economy: A case study in the villages of Gazipur Sadar Upazila of central Bangladesh     

Md. Motiur Rahman  Yasushi Furukawa  Isao Kawata  Mohammed Mahabubur Rahman  Mahbubul Alam 《Small-Scale Forestry》2005,4(3):359-376

This study examines the species composition, diversity and economic importance of homestead forests in the household economy of central Bangladesh. The study documents 57 homestead forest species and their main usage in 90 households across three villages of Gazipur Sadar Upazila. Homestead forests in Bangladesh comprise a mixture of fruit, timber and bamboo species. While superficially homestead forestry appears unimportant in rural livelihoods, in reality the contribution is huge, both as a source of food security and for other necessary household materials. A clear understanding of the physical characteristics and economic role of homestead forests in rural livelihoods is vital for ensuring sustainable resource management. Income and production of homestead forestry on a per hectare basis are found to vary widely between landholding size classes. Significant relationships are identified between forest performance (production and income) and species richness and education level. Homestead forestry appears to be a potential subsistence income generating land-use practice in the study area. The economic scope of homestead forestry can be further enhanced provided the appropriate species composition of the forest is achieved and the education of forest owners is ensured through targeted management and policy interventions.  相似文献   

The effect of ethylene and of inhibitors of protein and nucleic acid syntheses on dormancy break and subsequent sprout growth   总被引：2，自引：0，他引：2  

S. M. M. Alam  D. P. Murr  L. Kristof 《Potato Research》1994,37(1):25-33

Summary Cycloheximide inhibited dormancy break and subsequent sprout growth of potato buds in the presence or absence of ethylene. Dormancy break was relatively insensitive to treatment with actinomycin D, in marked contrast to the inhibition observed with cycloheximide; however, sprout elongation was inhibited by actinomycin D treatment. This suggests that dormancy release may depend on protein synthesis but not on nucleic acid synthesis. Total protein analysis revealed that two high molecular weight polypeptide bands appeared during dormancy break in the presence or absence of ethylene. The response was consistent in the two cultivars used in this study. Cycloheximide treatment blocked the synthesis of any new polypeptides in response to ethylene in the tuber tissue. This indicates that dormancy release of potato buds may be associated with the regulation of protein synthesis.  相似文献   

Silicate Minerals as a Source of Arsenic Contamination in Groundwater     

Alam  Md. Samrat  Wu  Yang  Cheng  Tao 《Water, air, and soil pollution》2014,225(11):1-15

The dynamic behavior of water quality and quantity in the Egyptian drains is often viewed as a disruption to the normal operation and performance of the process of water reuse in irrigation. The control of such behavior has been challenging and often elusive in practice. Therefore, this paper presents a framework to advance the understanding and opportunities for improving the reuse process by developing a multivariate process control model. The model starts with preliminary analysis for water quality data that are collected at the reuse site on the examined drain. This phase comprises investigating data distribution and dependency. Then, univariate control charts are used to investigate the state of control for the independent and normally distributed variables. For dependent variables, principal components analysis is used as a method of synthesizing the variables information. In this case, principal component scores are displayed using multivariate control charts. If in-control case existed, process capability index is used to provide a numerical measure of whether or not the reuse process is capable of producing water that satisfies the irrigation quality standards. Since the model will only detect assignable causes if out-of-control or in-capable case existed, management, operational, and/or engineering action will usually be necessary to sustain the reuse process. In these cases, an action plan in response to the model signals will be vital. The main function of the proposed model is to safely manage the reuse practice using statistical quality control techniques. The model was demonstrated using water quality data collected during the period from January 2006 to July 2011 from Hanut (EH02) and El-Salam 3 (ESL03) pump stations along Hadus drain, Eastern Nile Delta-Egypt. The recommended model is automatic, algorithmic, self-tuning, and computerizable.  相似文献   

Diversity and structural composition of species in dipterocarp forests: a study from Fasiakhali Wildlife Sanctuary,Bangladesh     

S. C. Das  M. S. Alam  M. A. Hossain 《林业研究》2018,29(5):1241-1249

Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan(Dipterocarpus spp.)trees.The present study assessed composition,structure and diversity of the species in this protected area.A total of 32 trees species were recorded with DBH ≥ 11 cm belonging to 24 genera and 19 families.The forest is low in plant diversity as represented by Shannon–Wiener diversity and Simpson Dominance indices.Dipterocarpus turbinatus was the most dominant species with maximum relative density,frequency,dominance,and importance value index.Syzygium firmum and Tectona grandis followed in terms of dominance.The structural composition indicated higher number of individuals in the medium growth classes(41 to 511 cm DBH and 16–20 m height ranges),whereas D.turbinatus was the only species that dominated most of the growth classes.Poor stem density in lower growth classes indicated meager recruitment of regeneration which may be due to lower annual precipitation,increased grazing and encroachments.This study will help to understand the patterns of tree species composition and diversity in the remnant dipterocarp forests of Bangladesh.It will also contribute to identifying threatened plants to undertake D.turbinatus based conservation and sustainable management of the Fasiakhali Wildlife Sanctuary.  相似文献   

Pre-sowing treatments for improved germination and growth of two rare native species of Bangladesh     

M. A. Hossain  K. S. Islam  N. Rajasree  M. K. Hossain  M. S. Alam 《林业研究》2018,29(5):1277-1282

Pre-sowing treatments are expected to increase seed germination. This evaluates response to pre-sowing treatments and the growth performance of two native and rare tree species, Garuga pinnata Roxb. and Vitex glabrata R. Br. The hard seed coats were treated by rubbing with sand paper, nail clipping, and immersion in water and acid (H₂SO₄). Results indicate that G. pinnata showed a 90% germination rate and 30% germination energy when seed coats were nicked with a nail clipper. Rubbing with sand paper was the best pre-sowing treatment for V. glabrata, resulting a 80% germination rate and 30% germination energy. G. pinnata and V. glabrata seedlings from seeds soaked 24 h in water resulted in maximum heights and collar diameters. These were significantly higher (at p < 0.05) than those of other treatments. The results indicate that scarification or nicking of seeds may have some negative impacts on seedling growth. Therefore, it is difficult to recommend a pre-sowing treatment of seeds for achieving both maximum germination and good early seedling growth.  相似文献   

Distribution of Trace Metals in Channel Sediment: a Case Study in South Atlantic Coast of Spain     

Md. Khurshid Alam Bhuiyan  Sabrina Qureshi  Md. Masum Billah  Suresh Varma Kammella  Md. Rushna Alam  Sunuram Ray  Md. Mostafa Monwar  Abu Hena M. K. 《Water, air, and soil pollution》2018,229(1):14

Recently, Sancti Petri channel on the southwestern (SW) part of Iberian Peninsula has been experiencing urban, industrial, and vehicular expansion. Until recently, there have been only few published reports documenting the pattern of metal accumulation in this estuarine sediment. In the present study, trace metals such as Cu, Zn, Ni, Mn, Pb, Co, Cd, As, and Hg concentrations were analyzed from 69 sediment samples collected from 23 sampling sites of the Santi Petri channel. The magnitude of trace metal accumulation found as the following trend: Mn > Zn > Cu > Pb > Ni > Co > As > Cd > Hg. Spatial distribution pattern demonstrated overall decreasing trend of trace metal from Cadiz Bay mouth to the open ocean mouth, clearly correlative to the presence of anthropogenic inputs. Results of the principle component analysis (PCA) revealed that sediment metal chemistry of Sancti Petri channel is mainly regulated by the concentrations of Pb, Cu, Zn, and Ni; possible sources of those were from vehicular-related emissions. Pollution load index (PLI) and geo-accumulation index (I _geo ) indicated overall low values. The study will stimulate improvement of our understanding regarding the pattern of accumulation of metals in the coastal sediments, and the recorded values of metals in the present study can be used as suitable reference for future studies.  相似文献   

Genetic variation in cadmium tolerance is related to transport and antioxidant activities in field peas (Pisum sativum L.)     

Mohammad Farhadur Rahman  Monirul Islam  Most Champa Begum  Mohammad Firoz Alam 《Archives of Agronomy and Soil Science》2017,63(4):578-585

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Pig manure digestate-derived biochar for soil management and crop cultivation in heavy metals contaminated soil     

Muhammad Ayaz  Urte Stulpinaite  Dalia Feiziene  Vita Tilvikiene  Kashif Akthar  Edita Baltrėnaitė-Gedienė  Nerijus Striugas  Urooj Rehmani  Sahib Alam  Rashid Iqbal  Monika Toleikiene  Modupe Doyeni 《Soil Use and Management》2022,38(2):1307-1321

Management of heavy metal-contaminated soil under drought and other harsh hydrological conditions is critical for protecting soil ecosystem services. In this study, we examined the effect of pig manure digestate-derived biochar as a soil amendment (15 t ha⁻¹) with N fertilizer (180 kg ha⁻¹) on soil and plant heavy metal levels and nutrient availability under various moisture regimes (optimal moisture ~15%, drought condition ≤5%, and flooded condition ≥35% wt.). It was observed that biochar applications significantly decreased heavy metals in the spring wheat plants, lowering Cr by 90%, Ni by 50%, Cd by 9% and Pb by 34% compared to non-biochar (control) treatments. However, the pig digestate-derived biochar increased heavy metals in soil under all moisture regimes, increasing soil Cr by 21%, Ni by 43%, Cu by 55%, Zn by 70%, and Pb by 12%. The availability of macroelements also increased with the biochar applications under the optimum moisture regimes in both soil and plants, increasing Mg²⁺ by 11%, P by 4%, K⁺ by 50%, and Ca²⁺ by 56% in the soil, and Mg²⁺ by 13%, P by 69%, K⁺ by 29, and Ca²⁺ by 39% in plants. Biochar addition also improved chlorophyll fluorescence (CF) levels in the crop for the entire season (12^th to 62^nd day) and the aboveground crop biomass and dry matter contents both increased. Consequently, the use of pig manure digestate-derived biochar with N fertilizer under normal moisture conditions was able to reduce heavy metal availability to plants and thus could be used in contaminated soils to maintain better crop growth and development.  相似文献